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Earth Sciences, Atmospheric Science; Electromagnetic fields, return strokes, dipole fields, accelerating charges, radiation fields, static fields, velocity fields
Online: 12 December 2018 (15:21:10 CET)
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Electric and/or magnetic fields are generated by stationary charges, uniformly moving charges and accelerating charges. These field components are described in the literature as static fields, velocity fields (or generalized Coulomb field) and radiation fields (or acceleration fields), respectively. In the literature, the electromagnetic fields generated by lightning return strokes are presented using the field components associated with short dipoles and in this description the one to one association of the electromagnetic field terms with the physical process that gives rise to them is lost. In this paper, we will derive expressions for the electromagnetic fields using field equations associated with accelerating (and moving) charges and separate the resulting fields into static, velocity and radiation fields. The results illustrates how the radiation fields emanating from the lightning channel give rise to field terms varying as inverse of distance and distance squired, the velocity fields generating field terms varying as inverse of distance squired and the static fields generating fields components varying as inverse of distance squired and distance cube. These field components depend explicitly on the speed of propagation of the current pulse. However, the total field does not depend explicitly on the speed of propagation of the current pulse. It is shown that these field components can be combined to generate the field components pertinent to the dipole technique. However, in this conversion process the connection of the field components to the physical process taking place at the source that generate these fields (i.e. static charges, uniformly moving charges and accelerating charges) is lost.
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Earth Sciences, Environmental Sciences; Ecosystem conservation, Policy instruments, Conservation planning, Assessment criteria, land use planning, Threatened ecosystems, Prioritization
Online: 12 December 2018 (13:09:56 CET)
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Threats to natural ecosystems are closely linked to human development, and the lack, insufficiency or inefficiency of public policies are some of the most important drivers of negative effects on the environment. The contribution of the IUCN’s Red List of Ecosystems (RLE) to conservation topics has been discussed in previous studies; however, to date its implications for conservation in public policies have not been addressed. This perspective discusses how the RLE may support the improvement and development of these policies, specifically through the implications for public policy of each of the criteria that substantiate the threat status of ecosystems. We aim to provide a plausible baseline to the operationalization of RLE in public and conservation policy, facilitating the work of governments, practitioners and decision makers. Finally, we provide recommendations and examples as to how to proceed in creating and modifying different public policy instruments, such as land-use planning, spatial zoning, tax reduction, compensation schemes, climate change adaptation plans, management of introduced species, development offsets and restoration investment. This perspective contributes to implement RLE into public policy and to improve ecosystem conservation by expanding the current scope of RLE into practical and political dimensions through plausible actions, policies and strategies.
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Earth Sciences, Environmental Sciences; drought; water management; thermal remote sensing; habitats protection; land surface temperature; CWSI
Online: 12 December 2018 (05:27:14 CET)
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The research carried out concerned the laboratory assessment of the applicability of the Crop Water Stress Index (CWSI) as a practical tool for assessing the risk of desiccation for selected wetland habitats: transition mires and quaking bogs as well as alkaline fens. The analysis was carried out on 3 soil samples with a vegetation cover (with the dimensions of 40×40×30 cm) collected during the full vegetation season for each mentioned habitat, with a characteristic species composition. Experimental research was carried out between 17th May 2018 and 19th June 2018. Thermal, RGB and multispectral images, chlorophyll content, volumetric soil moisture, air temperature and relative humidity measurements were taken for each sample every two days. The obtained results clearly indicate the dependence between CWSI and plant condition parameters in the first phase of desiccation. At the same time, as a result of the observations taken, thresholds have been set, indicating different desiccation phases.
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Earth Sciences, Geoinformatics; Land subsidence; InSAR; Small baseline interferometry; Mann-Kendall mutation test; Fishnet
Online: 11 December 2018 (16:49:47 CET)
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Since the 1970s, land subsidence has been developing rapidly in the Beijing Plain, the systematic study of its evolution mechanism is of great significance to the sustainable development of the regional economy. First, based on ENVISAT ASAT and RADARSAT2 data, the land subsidence data in Beijing Plain were obtained using permanent interferometer technology. Second, based on the GIS platform and using fishing net tools, vector data of ground settlement with different resolutions were obtained. Through a series of tests, a scale of 960 metres was selected as the research unit, and the subsidence rate of the grid was obtained from 2004 to 2015. Finally, based on the Mann-Kendall mutation test method, a trend analysis of land subsidence changes in various grids was carried out. The results showed that single-year mutation mainly distributed in the middle and lower parts of the Yongding River alluvial fan and the Chaobai River alluvial fan, mainly occurring in 2015, 2005 and 2013, respectively. The upper and middle alluvial fan of the Chaobai River, the vicinity of the emergency water source and the edge velocity of the groundwater funnel have undergone several sudden changes. Combined with hydrogeology, basic geological conditions and the impact of the South-to-North Water transfer project, we analysed the causes of the mutations in the grid. The research results can provide a basis for the study and prevention of land subsidence in this area and help to further explore the trend characteristics of land subsidence in this area.
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Earth Sciences, Geoinformatics; Radiation risk analysis, GIS based model, thermal power plant, surface radiation, remedial measures
Online: 11 December 2018 (13:57:09 CET)
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Coal combustion in thermal power plants releases ash. Ash is reported to cause different adverse health hazards in humans and other organisms. Owing to the presence of radionuclides, it is also considered as a potential radiation hazard. In this study, based on the surface radiation measurements and relevant ancillary data, expected radiation risk zones were identified with regard to the human population residing near the Thermal Power Plant. With population density as the risk determining criteria, about 20% of the study area was at ‘High’ risk and another 20% of the study area was at ‘Low’ risk zone. The remaining 60% was under medium risk zone. Based on the findings remedial measures which may be adopted have been suggested.
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Earth Sciences, Environmental Sciences; marginal bank; unsteady flow; different slopes; water flow structure; experimentation; Yangtze River
Online: 10 December 2018 (16:42:41 CET)
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Unsteady flow is the most common and complicated form of fluid motion in nature. This paper takes the beaches of key waterways in the middle and lower reaches of the Yangtze River as the research object, analyzes the water surface distribution and average flow velocity distribution near the beach, and analyzes the differences. The relationship between the flow pattern of the steep slope and the water flow pattern of the entire survey area and the steep slope of the beach and its nearby water flow structure. The water flow near the beach is divided into four major blocks: the swelling water area, the falling water area, the backwater area and the maximum flow rate area. The water flow structure characteristics and the cause of each block are analyzed.
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Earth Sciences, Space Science; Two-dimensional principal component analysis (2DPCA), 2D total electron content (TEC), TEC precursors, NASA Global Differential GPS (GDGPS) network, China Ludian earthquake, principal component analysis (PCA), Radon-gas release, Coulomb stress transfer theory
Online: 10 December 2018 (15:12:12 CET)
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Two-dimensional principal component analysis (2DPCA) was performed to examine ionospheric 2D total electron content (TEC) variations obtained from the NASA Global Differential GPS (GDGPS) network, which consisted of low spatial resolution ionospheric TEC data, to detect TEC precursors prior to the China Ludian earthquake at 08:30:13 UT on 03 August 2014 (M = 6.1). Results have shown that two TEC precursors were observed three days prior to this earthquake. The characteristics of all principal eigenvalues were considered to determine the TEC precursors of the earthquake in this study. This study aimed to differentiate the previous studies of Lin about PCA and 2DPCA using only the characteristic of the first principal eigenvalue to determine the TEC precursors of the earthquake. However, some other TEC precursors could be lost in processes that do not analyze characteristics of other principal eigenvalues. Therefore, this research can be considered as a full analysis that examined the detailed surrounding TEC precursors of the earthquake and could be treated as a new study scope. The TEC precursor during 06:15 to 06:20 (UT) on 01 August 2014 localized near the epicenter was more intense compared with the characteristic of the first largest principal eigenvalue. However, another localized TEC precursor from 06:15 to 06:20 (UT) on 01 August 2014 was found to be more intense, which was far from the epicenter east of the first largest principal eigenvalue. The more plausible reason for the two TEC precursors could be the density variances caused by radon-gas release due to the fine crack stress transfer from the rocks according to Coulomb stress transfer theory as applied to a far TEC precursor. The durations of both TEC precursors were at least 5 min. This research could be treated as a full and detailed examination of surrounding TEC precursors.
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Earth Sciences, Environmental Sciences; Pakistan; Climate change; Rice production; ARDL
Online: 7 December 2018 (17:26:03 CET)
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This research paper aims to examine the relationship between CO2, temperature, area, fertilizers and rice production in Pakistan. This study used Augmented Dickey Fuller (ADF) and Phillips Perron (PP) unit root tests to check the order of integration of each variable. The cointegration analysis with ARDL bounds testing approach is used to examine the impact of climate change on rice production in Pakistan over time series data from the period 1968 to 2014. The parameter stability test of the model is also checked at the end. The results of estimation show that the important variables of the study are cointegrated demonstrating the presence of long-run association among them. Furthermore, climate change factors, e.g. CO2 and temperature have a long-run and short-run positive effect on the production of rice in Pakistan. This present work is original and it is first time empirically tested the impact of climate change on rice production in Pakistan. The annual time series data of 47 years enhances the validity of the empirical findings. The most fruitful finding of this research is that rice production in Pakistan is positively influenced by emission of carbon dioxide (CO2) at 5 percent significance level in both long-run and short-run.
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Earth Sciences, Environmental Sciences; Soil moisture; Fengyun-3C; Passive microwave; Chinese Automatic Soil Moisture Observation Stations; NDVI
Online: 5 December 2018 (14:05:35 CET)
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Soil moisture (SM) products derived from passive satellite missions are playing an increasingly important role in agricultural applications, especially in crop monitoring and disaster warning. Evaluating the dependability of those products before they can be used on a large scale is crucial. In this study, we assessed the level 2 (L2) SM product from the Chinese Fengyun-3C (FY-3C) radiometer against in situ measurements collected from the Chinese Automatic Soil Moisture Observation Stations (CASMOS) during a one-year period from January 1 to December 31, 2016 in Henan, which is an agricultural province in China. Four statistical parameters were used to evaluate the products’ reliability: mean difference, root-mean-square error (RMSE), unbiased RMSE (ubRMSE), and the correlation coefficient. These statistical indicators revealed that the FY-3C L2 SM product generally did not agree with the in situ SM data from CASMOS. The time-series analysis further indicated that the correlations and estimated error were highly related to the growing periods of the crops in our study area. FY-3C L2 SM data tended to overestimate soil moisture during May, August, and September, when the crops reach their maximum vegetation density, and tended to underestimate the soil moisture content during the rest of the year. The averaged correlation coefficient between FY-3C SM and the Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index was 0.55, which demonstrates that the vegetation water content of the crops considerably influences the SM product. To improve the accuracy of the FY-3C SM product, an improved algorithm that can filter out the influences of the crops should be applied in the future.
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Earth Sciences, Environmental Sciences; built-up area; classification; Landsat 8- OLI; feature engineering; feature learning; CNN; accuracy evaluation
Online: 5 December 2018 (12:06:34 CET)
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Detailed built-up area information is valuable for mapping complex urban environments. Although a large number of classification algorithms about built-up areas have been developed, they are rarely tested from the perspective of feature engineering and feature learning. Therefore we launched a unique investigation to provide a full test of the OLI imagery for 15-m resolution built-up area classification in 2015, in Beijing, China. Training a classifier requires many sample points, and we propose a method based on the ESA's 38-meter global built-up area data of 2014, Open Street Map and MOD13Q1-NDVI to achieve rapid and automatic generation of a large number of sample points. Our aim is to examine the influence of a single pixel and image patch under traditional feature engineering and modern feature learning strategies. In feature engineering, we consider spectra, shape and texture as the input features, and SVM, random forest (RF) and AdaBoost as the classification algorithms. In feature learning, the convolution neural network (CNN) is used as the classification algorithm. In total, 26 built-up land cover maps were produced. Experimental results show that: (1) the approaches based on feature learning are generally better than those based on feature engineering in terms of classification accuracy, and the performance of ensemble classifiers e.g., RF, is comparable to that of CNN. Two dimensional CNN and the 7 neighborhood RF have the highest classification accuracy of nearly 91%. (2) Overall, the classification effect and accuracy based on image patches are better than those based on single pixels. The features that can highlight the information of the target category (for example, PanTex and EMBI) can help improve classification accuracy.
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Earth Sciences, Other; Carpathians; Balkan peninsula; holocene; hydroclimate; cryogenic cave carbonate; carbon; oxygen
Online: 4 December 2018 (02:46:38 CET)
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The region of Eastern Europe & Turkey contributed to the SISAL (Speleothem Isotopes Synthesis and AnaLysis) global database with stable carbon- and oxygen isotope time-series from 18 entities from 14 cave systems. The currently available oldest record from this region is the ABA-2 flowstone record (Abaliget Cave; Hungary) reaching back to MIS 6. The temporal distribution of the compiled 18 entities points out a ~20-kyr-long period, centering around 100 ka, lacking speleothem stable isotope record in the region. The regional subset of SISAL_v1 records displays a continuous coverage for the past ~90 kyr for both δ18O and δ13C, with a mean temporal resolution of ~12 yr for the Holocene, and >50 yr for the pre-Holocene period. The highest temporal resolution both for the Holocene and the pre-Holocene was achieved in the So-1 record (Sofular Cave; Turkey). Assessing the data, an important split was found regarding the climatic interpretation of speleothem δ18O. While the oxygen isotope composition of more continental formations is thought to reflect mainly temperature variations and changes in moisture transport trajectories, it may strongly reflect fluctuations of precipitation amount in the southern part of the region. Variations of δ13C primarily interpreted as humidity changes reflecting dry/wet periods across the region. Elevation gradients from three non-overlapping time periods from the region - for the last 5kyr - indicated systematically prevailing elevational gradients around -0.26‰ 100m-1 in δ18O. The regional comparison of SISAL_v1 speleothem δ18O and the temporal distribution of coarsely crystalline cryogenic cave carbonate occurrences back to 45ka does not appear to confirm the finding that occurrence of the latter coincides with the warming from stadial to interstadial conditions.
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Earth Sciences, Environmental Sciences; irrigation zone; Tibetan Plateau; non-point source pollution; Sobol’ sensitivity analysis; subsurface lateral flow
Online: 3 December 2018 (13:48:44 CET)
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Flow and transport processes in soil and rock play a critical role in agricultural non-point source pollution (ANSP) loads. In this study, we investigated the ANPS load discharged into rivers from an irrigation district in the Tibetan Plateau, and simulated ANPS load using a distributed model involving detailed descriptions of flow and ANPS transport and transformation processes in the soil and rock. Experiments were conducted for two years to measure soil water content and nitrogen concentrations and the quality and quantity of lateral flow in the rock and at the drainage canal outlet during the highland barley growing period. A distributed model, in which the subsurface lateral flow was described using a step-wise method, was developed to simulate flow and ammonium nitrogen and nitrate nitrogen transport. Sobol’s method was used to evaluate the sensitivity of simulated flow and transport processes to model inputs. The results showed that, with a 21.2% increase of rainfall and irrigation in the highland barley growing period, the average NH4+-N and NO3--N concentrations in the soil layer decreased by 10.8% and 14.3%, respectively, due to increased deep seepage. Deep seepage of rainfall water accounted for 0–52.4% of total rainfall, whereas deep seepage of irrigation water accounted for 36.6–45.3% of total irrigation. NH4+-N and NO3--N discharged into the drainage channel represented 19.9–30.4% and 19.4–26.7% of the deep seepage, respectively. The mean Nash-Sutcliffe coefficients, root mean square errors, and cumulative deviations between the measured and simulated flow rates and NH4+-N and NO3--N concentrations at the surface drainage canal outlet were 0.694, 0.081, and 0.242, respectively, indicating that the proposed method can effectively describe the hydrological and ANPS pollution migration in the plateau irrigation zone. The Sobol’ sensitivity analysis results demonstrated that subsurface lateral flow had the most important first order and total effect on the simulated flow and NH4+-N and NO3--N concentrations at the surface drainage outlet.
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Earth Sciences, Environmental Sciences; Landsat; artisanal-scale gold mining; infrastructure; protected areas; commodity
Online: 30 November 2018 (10:02:42 CET)
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While deforestation rates decline globally they are rising in the Western Amazon. Artisanal-scale gold mining (ASGM) is a large cause of this deforestation and brings with it extensive environmental, social, governance, and public health impacts, including large carbon emissions and mercury pollution. Underlying ASGM is a broad network of factors that influence its growth, distribution, and practices such as poverty, flows of legal and illegal capital, conflicting governance, and global economic trends. Despite its central role in land use and land cover change in the Western Amazon and the severity of its social and environmental impacts, it is relatively poorly studied. While ASGM in Southeastern Peru has been quantified previously, doing so is difficult due to the heterogeneous nature of the resulting landscape. Using a novel approach to classify mining that relies on a fusion of CLASlite and the Global Forest Change dataset, two Landsat-based deforestation detection tools, we sought to quantify ASGM-caused deforestation in the period 1984–2017 in the southern Peruvian Amazon and examine trends in the geography, methods, and impacts of ASGM across that time. We identify nearly 100,000 ha of deforestation due to ASGM in the 34-year study period, an increase of 21% compared to previous estimates. Further, we find that 10% of that deforestation occurred in 2017, the highest annual amount of deforestation in the study period, with 53% occurring since 2011. Finally, we demonstrate that not all mining is created equal by examining key patterns and changes in ASGM activity and techniques through time and space. We discuss their connections with, and impacts on, socio-economic factors, such as land tenure, infrastructure, international markets, governance efforts, and social and environmental impacts.
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Earth Sciences, Geology; ordinary Kriging; variogram; jack-knifing; upper miocene; northern Croatia; porosity
Online: 29 November 2018 (03:53:34 CET)
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Presented is semivariogram and the Ordinary Kriging analyses of porosity data from the Sava Depression (Northern Croatia), as part of the Croatian part of the Pannonian Basin System. Data are taken from hydrocarbon reservoirs of the Lower Pontian (Upper Miocene) age, which belongs to the Kloštar-Ivanić Formation. Original datasets had been jack-knifed with purpose to “artificially” increased data and calculate the more reliable semivariograms. The results showed that such improvements can assist in the interpolation of more reliable maps. The both sets, made by original and jack-knifed data, need to be compared using geological recognition of non-allowed shapes (“bull-eyes”, “butterfly effects”) as well as cross-validation results. That comparison made possible to select the most appropriate porosity interpolation.
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Earth Sciences, Geophysics; geophysical signal processing; pattern recognition; temporal convolutional neural networks; seismology; deep learning; nuclear treaty monitoring
Online: 29 November 2018 (03:37:48 CET)
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The detection of seismic events at regional and teleseismic distances is critical to Nuclear Treaty Monitoring. Traditionally, detecting regional and teleseismic events has required the use of an expensive multi-instrument seismic array; however in this work, we present DeepPick, a novel seismic detection algorithm capable of array-like performance from a single trace. We achieve this directly, by training our single-trace detector against labeled events from an array catalog, and by utilizing a deep temporal convolutional neural network. The training data consists of all arrivals in the International Seismological Centre Catalog for seven seismic arrays over a five year window from 1 Jan 2010 to 1 Jan 2015, yielding a total training set of 608,362 detections. The test set consists of the same seven arrays over a one year window from 1 Jan 2015 to 1 Jan 2016. We report our results by training the algorithm on six of the arrays and testing it on the seventh, so as to demonstrate the transportability and generalization of the technique to new stations. Detection performance against this test set is outstanding. Fixing a type-I error rate of 1%, the algorithm achieves an overall recall rate of 73% on the 141,095 array beam picks in the test set, yielding 102,394 correct detections. This is more than 4 times the 23,259 detections found in the analyst-reviewed single-trace catalogs over the same period, and represents an 8dB improvement in detector sensitivity over current methods. These results demonstrate the potential of our algorithm to significantly enhance the effectiveness of the global treaty monitoring network.
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Earth Sciences, Geoinformatics; SDGs; urban inequality; urban governance; inclusive development; participatory geospatial methods; citizen-generated data; data practices; urban indicators
Online: 29 November 2018 (03:16:51 CET)
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There is much discussion regarding the Sustainable Development Goals’ (SDGs) capacity to promote inclusive development. While some argue that they represent an opportunity for goal-led alignment of stakeholders and evidence-based decision-making, other voices express concerns as they perceive them as a techno-managerial framework that measures development according to quantitatively defined parameters and does not allow for local variation. We argue that the extent to which the positive or negative aspects of the SDGs prevail depends on the monitoring system’s ability to account for multiple and intersecting inequalities. The need for sub-nationally (urban) representative indicators poses an additional methodological challenge – especially in cities with intra-urban inequalities related to socio-spatial variations across neighbourhoods. This paper investigates the extent to which the SDG indicators’ representativeness could be affected by inequalities. It does so by proposing a conceptual framing for understanding the relation between inequalities and SDG monitoring, which is then applied to analyse the current methodological proposals for the indicator framework of the “urban SDG”, Goal 11. The outcome is a call for 1) a more explicit attention to intra-urban inequalities, 2) the development of a methodological approach to “recalibrate” the city-level indicators to account for the degree of intra-urban inequalities, and 3) an alignment between methodologies and data practices applied for monitoring SDG 11 and the extent of the underlying inequalities within the city. This would enable an informed decision regarding the trade-off in indicator representativeness between conventional data sources, such as censuses and household surveys, and emerging methods, such as participatory geospatial methods and citizen-generated data practices.
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Earth Sciences, Environmental Sciences; water resources; natural resources; resource security; SDGs; goal; target; benchmark; standard
Online: 28 November 2018 (14:03:52 CET)
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The 2030 Agenda for Sustainable Development, the SDGs, are high on the agenda for most countries of the world. In its publication of the SDGs, the UN has provided the goals and target descriptions that, if implemented at a country level, would lead towards a sustainable future. The IAEG (InterAgency Expert Group of the SDGs) was tasked with disseminating indicators and methods to countries that can be used to gather data describing the global progress towards sustainability. However 2030 Agenda leaves it to countries to adopt the targets with each government setting its own national targets guided by the global level of ambition but taking into account national circumstances. At present, guidance on how to go about this is scant, but it is clear that the responsibility is with countries to implement and that it is actions at a country level that will determine the success of the SDGs. SDG reporting by countries takes on two forms 1) global reporting using prescribed indicator methods and data; 2) National Voluntary Reviews where a country reports on its own progress in more detail but is also able to present data that are more appropriate for the country. For the latter, countries need to be able to adapt the global indicators to fit national priorities and context, thus the global description of an indicator could be reduced to describe only what is relevant to the country. Countries may also, for the National Voluntary Review, use indicators that are unique to the country but nevertheless contribute to measurement of progress towards the global SDG target. Importantly, for those indicators that relate to the security of natural resources security (e.g. water) indicators, there are no prescribed numerical targets/standards or benchmarks. Rather countries will need to set their own benchmarks or standards against which performance can be evaluated. This paper presents a procedure that would enable a country to describe national targets with associated benchmarks that are appropriate for the country. The procedure focusses on those SDG targets that are natural resource-security focussed e.g. extent of water-related ecosystems (6.6), desertification (15.3) etc., because the selection of indicator methods and benchmarks is based on the location of natural resources, their use and present state and how they fit into national strategies.
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Earth Sciences, Geology; R, statistical analysis, programming, Mariana trench, oceanography, geomorphology
Online: 28 November 2018 (10:28:16 CET)
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This paper introduces an application of R programming language for geostatistical data processing with a case study of the Mariana Trench, Pacific Ocean. The formation of the Mariana Trench, the deepest among all hadal oceanic depth trenches, is caused by complex and diverse geomorphic factors affecting its development. Mariana Trench crosses four tectonic plates: Mariana, Caroline, Pacific and Philippine. The impact of the geographic location and geological factors on its geomorphology has been studied by methods of statistical analysis and data visualization using R libraries. The methodology includes following steps. Firstly, vector thematic data were processed in QGIS: tectonics, bathymetry, geomorphology and geology. Secondly, 25 cross-section profiles were drawn across the trench. The length of each profile is 1000-km. The attribute information has been derived from each profile and stored in a table containing coordinates, depths and thematic information. Finally, this table was processed by methods of the statistical analysis on R. The programming codes and graphical results are presented. The results include geospatial comparative analysis and estimated effects of the data distribution by tectonic plates: slope angle, igneous volcanic areas and depths. The innovativeness of this paper consists in a cross-disciplinary approach combining GIS, statistical analysis and R programming.
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Scott D. Chambers,
Elise-Andree Guérette,
Khalia Monk,
Alan D. Griffiths,
Yang Zhang,
Hiep Duc,
Martin Cope,
Kathryn M. Emmerson,
Lisa T. Chang,
Jeremy D. Silver,
Steven Utembe,
Jagoda Crawford,
Alastair G. Williams,
Melita Keywood
Earth Sciences, Atmospheric Science; radon; atmospheric stability; air quality; model evaluation; modelling; SNBL; ABL; urban pollution
Online: 28 November 2018 (07:00:41 CET)
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We propose a new technique to prepare statistically-robust benchmarking data for evaluating chemical transport model meteorology and air quality parameters within the urban boundary layer. The approach employs atmospheric class-typing, using nocturnal radon measurements to assign atmospheric mixing classes, and can be applied temporally (across the diurnal cycle), or spatially (to create angular distributions of pollutants as a top-down constraint on emissions inventories). In this study only a short (<1-month) campaign is used, but grouping of the relative mixing classes based on nocturnal mean radon concentrations can be adjusted according to dataset length (i.e., number of days per category), or desired range of within-class variability. Calculating hourly distributions of observed and simulated values across diurnal composites of each class-type helps to: (i) bridge the gap between scales of simulation and observation, (ii) represent the variability associated with spatial and temporal heterogeneity of sources and meteorology without being confused by it, and (iii) provide an objective way to group results over whole diurnal cycles that separates ‘natural complicating factors’ (synoptic non-stationarity, rainfall, mesoscale motions, extreme stability, etc.) from problems related to parameterizations, or between-model differences. We demonstrate the utility of this technique using output from a suite of seven contemporary regional forecast and chemical transport models. Meteorological model skill varied across the diurnal cycle for all models, with an additional dependence on the atmospheric mixing class that varied between models. From an air quality perspective, model skill regarding the duration and magnitude of morning and evening “rush hour” pollution events varied strongly as a function of mixing class. Model skill was typically the lowest when public exposure would have been the highest, which has important implications for assessing potential health risks in new and rapidly evolving urban regions, and also for prioritizing the areas of model improvement for future applications.
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Earth Sciences, Environmental Sciences; Indonesia, biofuel, land restoration, pongamia
Online: 27 November 2018 (12:20:35 CET)
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Indonesia has a large area of degraded land, i.e. 30 million ha, which could potentially be utilized for biofuel plantations. The leguminous tree pongamia (Pongamia pinnata syn. Milettia pinnata) could be utilized to produce biofuel while restoring degraded land. Here, we explore the potential of pongamia as a source of biofuel and for restoring degraded land in Indonesia. Pongamia occurs across Indonesia, in Sumatra, Java, Bali, West Nusa Tenggara and Maluku. It grows to a height of 15–20 m and can grow in a range of environmental conditions. Its seeds can generate up to 40% crude oil by weight. It can help to restore degraded land and improve soil properties. Pongamia also provides wood, fodder, medicine, fertilizer and biogas. Therefore, as a multipurpose species, pongamia holds great potential to combat Indonesia’s energy crisis and to restore much of the degraded land.
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Earth Sciences, Environmental Sciences; Dust; Mining; Environment; Sustainability; community health; occupational health
Online: 27 November 2018 (12:10:56 CET)
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Dust inhalation is a huge concern in the mining environment and within all its operations. In fact, dust to be one of the most serious occupational hazards in the mining industry. Coal and crystalline silica dust are the causes of serious, sometimes fatal lung diseases such as pneumoconiosis, which affects coal miners, as well as silicosis, tuberculosis, chronic bronchitis, emphysema, chronic obstructive pulmonary disease, and chronic renal disease, which affect coal and other types of miners. The resulting effects both affect workers and nearby communities. The mining industry has in the past, employed several approaches to reduce effects of dust. But these strategies have often been ineffective because the grass withers during the dry season and sprayed water is rapidly absorbed or evaporates. This paper endeavors to review information on dust in the mining environment and how it is a nuisance to workers and communities and establish what strategies exist for this.
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Earth Sciences, Atmospheric Science; global energy budget; simple greenhouse model; infrared-opaque limit
Online: 27 November 2018 (03:47:23 CET)
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Earth atmosphere is almost opaque in the infrared: about 374 W/m2 is absorbed by the atmosphere out of 396 W/m2 surface upward longwave radiation, and only about 22 W/m2 leaves the system unabsorbed in the atmospheric window. This makes rise to the idea to approximate the annual global mean energy flow system from a simple idealized greenhouse model, where the surface is surrounded by a single-layer shortwave (SW) transparent, longwave (LW) opaque, non-turbulent atmosphere. The energy flows in this geometry can be described by elementary arithmetic relationships. Starting from this model, the realistic Earth’s atmosphere can be achieved by introducing partial atmospheric SW opacity, partial atmospheric LW transparency and turbulent fluxes during the course of the deduction. The resulted global mean energy flow system is then compared to several data sets such as satellite observations from the CERES mission; estimates using direct surface observations and climate models; global energy and water cycle assessments; and independent detailed clear-sky radiative transfer computations. We find that the deduction from this idealized model approximates the real values in Earth energy budget with reasonable accuracy: the deduced fluxes and the observed ones are consistent within the acknowledged error of observations; while fundamental features of the initial geometry like special ratios and definite relationships between the fluxes are preserved.
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Earth Sciences, Atmospheric Science; Tornadoes; CAPE; Overview; Case Study; Klerksdorp; South Africa
Online: 26 November 2018 (10:02:42 CET)
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This paper contributes to the understating of tornadoes in South Africa using case study analysis. In South Africa tornadoes are the recurring phenomenon (the climatology) but so far they have received less attention. Damages from storms itself (tornadoes inclusive) are significant in South Africa relative to other weather-related disasters for example floods, heat waves, and droughts. For their understanding, a case study approach was adopted in the current study. Data were in courtesy of the following, National Oceanic and Atmospheric Administration (NOAA), National Centers for Environmental Predictions (NCEP), Eumetsat Germany, and South African Weather Service (SAWS). The aim of the study was to provide an overview of the occurrence of tornadoes in South Africa using a Klerksdorp tornado, which occurred on March 4, 2007, Northwest Province in South Africa. From the case study analysis, the tornado was associated with the cold front and cut-off low (both are extratropical circulation) which were the dominant weather systems of the day. Therefore we conclude that, a case study approach may be the best way to study events of these nature for a more informed decision, for example, issuing an early warning system. In future, case studies, for example, involving interaction between extratropical and tropical circulation will also be an interesting study.
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Earth Sciences, Environmental Sciences; CWSI, Natura 2000, thermal remote sensing, wetlands, land surface temperature
Online: 23 November 2018 (12:27:52 CET)
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Droughts occurring more and more frequently in recent years are usually associated with progressive climate changes. Modern monitoring methods is mainly associated with agricultural use due to the high market demand for services protecting against agricultural losses. In natural wetland ecosystem this problem is neglected which is probably due to fact that this are ecosystems rich in water by definition. Nevertheless this droughts might become a problem of wetlands, whose good condition depends on adequate hydration. Therefore this study focused on determination Crop Water Stress Index (CWSI) for natural heterogeneous wetland habitats. CWSI based on remotely sensed land surface temperature and associated basic meteorological (air temperature and humidity) measurements. CWSI was calculated based on high resolution LST measurements from UAV platform and compare with on ground measurements of soil moisture, CCI, fAPAR and meteorological conditions. Results shows that CWSI properly shows water condition of plants in measured habitats and revels high importance of metrological conditions during data acquisition.
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Earth Sciences, Geoinformatics; Calving Front; Image Segmentation; U-Net; Convolutional Neural Network; Machine Learning; Greenland
Online: 21 November 2018 (14:05:00 CET)
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The continuous and precise mapping of glacier calving fronts is essential for monitoring and understanding rapid glacier changes in Antarctica and Greenland, which have the potential for significant sea level rise within the current century. This effort has been mostly restricted to the slow and painstaking manual digitalization of the calving front positions in thousands of satellite imagery products. Here, we have developed a machine learning toolkit to robustly and automatically detect glacier calving front margins in satellite imagery. The toolkit is based on semantic image segmentation using Convolutional Neural Networks (CNN) with a modified U-Net architecture to isolate the calving fronts from satellite images after having been trained with a dataset of images and their corresponding manually-determined calving fronts. As a case study we train our neural network on a varied set Landsat images with lowered resolutions from Jakobshavn, Sverdrup, and Kangerlussuaq glaciers, Greenland and test the results on novel images from Helheim glacier, Greenland to evaluate the performance of the approach. The neural network is able to identify the calving front in new images with a mean deviation of 96.3 m from the true fronts, equivalent to 1.97 pixels on average, while the corresponding error for manually-determined fronts on the same resolution images is 92.5 m. We find that the trained neural network significantly outperforms common edge detection techniques, and can be used to continuously map out calving-ice fronts with a variety of data products.
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Earth Sciences, Environmental Sciences; phosphorus; nutrient budget; non-point source pollution; Korea; monsoon climate
Online: 21 November 2018 (07:28:35 CET)
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Despite increased awareness of and attention to the need for sustainable agriculture, fertilizers and compost application in excess of crop requirements remain common agricultural practices in South Korea, causing eutrophication of freshwater and coastal ecosystems. In this study, a phosphorus (P) budget was developed to quantify P inputs, outputs, and retention in a forested- agricultural watershed. The P budget showed that chemical fertilizers and organic compost were the largest source of P (97.6% of the total) followed by atmospheric deposition (2.1% of the total P), whereas forest export (0.2% of the total) and sewage treatment plants (STPs) (0.1% of the total) were negligible. The dominant P outputs were crop harvesting and hydrologic export to surface water. The P balance showed a significant accumulation of P in the watershed; approximately 87% of the total P input was retained in the soils within the watershed. However, P concentrations in drainage water were still high enough to cause eutrophication of downstream reservoirs. The results provide useful information on the proportion of P export and retention in soils and will help support efforts to improve water quality and design better management of agricultural non-point source pollution.
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Earth Sciences, Geoinformatics; GDP; nighttime lights; agriculture; development
Online: 21 November 2018 (07:13:10 CET)
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Uganda is one of the poorest nations in the world. To address the developmental challenges and understand social and economic status, it is important to obtain accurate data in a timely manner. Many studies have demonstrated that nighttime lights (NTL) can be used to measure human activities. Nevertheless, methods developed from these studies (1) suffer from coarse resolutions, (2) fail to capture the nonlinearity and multi-scale variability of geospatial data, and (3) perform poorly for agriculture-dependent regions. This study proposes a new enhanced light intensity model (ELIM) to estimate the Gross Domestic Product (GDP) at sub-national scales for Uganda. This model is developed by combining the NTL data from the Suomi National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS), the population data from the Global Human Settlement Layer (GHSL), and information on agricultural production and market prices across several commodity types. This resulted in a gridded dataset for GDP and GDP per capita for Uganda at 1 km spatial resolution and district level to capture the spatial heterogeneity in economic activity.
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Earth Sciences, Other; soil stoichiometry; soil nutrient; nutrient limitations; natural grassland; natural forest
Online: 20 November 2018 (09:35:23 CET)
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The Loess Plateau is an important region for vegetation restoration in China, however, changes in soil organic carbon (SOC), soil nutrients, and stoichiometry after restoration in this vulnerable ecoregion are not well understood. Typical restoration types, including orchardland (OL), grassland (GL), shrubland (SL), and forestland (FL) were chosen to examine changes in the stocks and stoichiometry of SOC, soil total nitrogen (TN), and soil total phosphorus (TP) at different soil depths and recovery times. Results showed that SOC stocks first increased and then stabilized in OL, GL, and SL at 0–30 cm depth, while in FL, stocks gradually increased. Soil TN stocks first increased and then decreased in OL, SL, and FL with vegetation age at 0–30 cm depth, while soil TP stocks showed little variation between restoration types. In the later stages of restoration, the stocks of SOC and soil TN at 0–30 cm soil depth were still lower than those in natural grassland (NG) and natural forest (NF). The overall C:N, C:P, and N:P ratios increased with vegetation age. Additionally, the SOC, soil TN and soil TP stocks, and C:N, C:P, and N:P ratios decreased with soil depth. The FL had the highest rate of change in SOC and soil TN stocks, at 0-10 cm soil depth. These results indicate a complex response of SOC, soil TN, and soil TP stocks and stoichiometry to vegetation restoration, which could have important implications for understanding C, N, and P changes and nutrient limitations after vegetation restoration.
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Earth Sciences, Geoinformatics; remotely sensed drought indices (RSDIs); Standardized Precipitation Evapotranspiration Index (SPEI); meteorological drought; Skill Score (SS); Yellow River basin (YRB)
Online: 19 November 2018 (17:26:37 CET)
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Due to the advantages of wide coverage and continuity, remotely sensed data are widely used for large-scale drought monitoring to compensate the deficiency and discontinuity of meteorological data. However, few researches have focused on the capability of various remotely sensed drought indices (RSDIs) for representing the spatio-temporal variations of the meteorological droughts. In this study, five RSDIs, namely Vegetation Condition Index (VCI), Temperature Condition Index (TCI), Vegetation Health Index (VHI), Modified Temperature Vegetation Dryness Index (MTVDI) and Normalized Vegetation Supply Water Index (NVSWI) were calculated using Moderate Resolution Imaging Spectroradiometer (MODIS) monthly NDVI and LST. The monthly NDVI and LST data were filtered by Savitzky-Golay (S-G) filtering method. Meteorological station-based drought index represented by Standardized Precipitation Evapotranspiration Index (SPEI) was compared with RSDIs. And the dimensionless Skill Score (SS) method was adopted to identify the spatiotemporally optimal RSDIs for presenting the meteorological droughts in the Yellow River basin (YRB) from 2000 to 2015. The results indicated that (1) RSDIs revealed a decreasing trend to the overall YRB consistent with SPEI except for in winter, and different variations of seasonal trends spatially; (2) the optimal RSDIs in spring, summer, autumn and winter were VHI, TCI, MTVDI and VCI, respectively, and the average correlation coefficient between the RSDIs and SPEI was 0.577 (=0.05); (3) different RSDIs have a 0–3 months’ time-lags compared with meteorological drought index.
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Earth Sciences, Geology; Malyy (Little) Murun massif; Aldan Shield; Siberian Craton; 40Ar/39Ar dating
Online: 19 November 2018 (12:45:06 CET)
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The Malyy (Little) Murun massif of the Aldan Shield of the Siberian Craton has long been a kind of the geologists’ Siberian Mecca. It attracted thousands of geologists, prospectors and mineral collectors despite of its remote location. It is famous for a dozen of new and rare minerals, including gemstones charoite and dianite (the latter is the market name for strontian potassicrichrerite), as well as for specific alkaline igneous rocks. Despite of this, the age of the Malyy Murun igneous complex and associated metasomatic and hydrothermal mineral associations remained poorly constrained. In this paper, we provide extensive 40Ar/39Ar geochronological data to reveal its age and temporal history. It appeared that being unique in terms of rocks and constituent minerals, the Malyy Murun is one of multiple alkaline massifs and lavas emplaced in Early Cretaceous (~137-128 Ma) within a framework of extensional setting of the Aldan Shield and nearby Transbaikalian region. The extension has occurred 40-60 million years after the supposed closure of the Mongolia-Okhotsk Ocean and peak of orogeny in Early-Middle Jurassic.
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Earth Sciences, Environmental Sciences; electronic waste recycling; occupational health; public health; injuries; stress
Online: 19 November 2018 (10:23:06 CET)
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Little research has been done on occupational health ramifications of informal electronic waste (e-waste) recycling work, which is increasingly common in low- and middle-income countries, and very little is known about this in high-income countries. Our study evaluated informal and formal e-waste recycling workers in Chile, which was recently recognized as a high-income country. In 2017 we recruited 78 informal recycling workers from two cities, and 15 formal e-waste recycling workers from one recycling facility. Participants completed a questionnaire and health assessment regarding their involvement in, and potential impacts of, e-waste recycling, among other measures. Participants were primarily male, middle-aged, married with children, and had worked in e-waste recycling for an average of 12 years. Participants generally reported good health status, and chronic disease prevalence was similar to the national prevalence. Workers commonly reported exposures to several occupational stressors, including mental health stressors and noise, as well as insufficient income. Occupational injuries were common and use of safety equipment was low. No significant differences were found between informal and formal workers. Informal e-waste workers in Chile face occupational health challenges. The extent to which these issues impact the health of informal Chilean e-waste workers is unclear and warrants further research.
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Earth Sciences, Environmental Sciences; biogas; renewable energy; anaerobic digestion; waste activated sludge; disintegration
Online: 19 November 2018 (09:57:56 CET)
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Due to rapid urbanization, the quantity of wastewater treatment plants (WWTP) has increased, and with it the amount of waste generated by them. Sustainable management of this waste can lead to the creation of energy-rich biogas through the fermentation process. This review presents recent advances in the anaerobic digestion process resulting in greater biogas production. Disintegration techniques for enhancing waste activated sludge fermentation can be generally partitioned into biological, physical and chemical, each of which are covered in this review. These disintegration techniques were compared mainly in terms of their biogas yield. It was found that ultrasonic and microwave disintegration provides the highest biogas yield (>500%); however, they are also the most energy demanding (>10,000 kJ kg-1 total solids).
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Earth Sciences, Other; altimetry; retracking; Sentinel-3; synthetic aperture radar (SAR)
Online: 19 November 2018 (06:55:41 CET)
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Satellite altimeters have been used to monitor river and reservoir water levels, from which water storage estimates can be derived. Inland water altimetry can therefore play an important role in continental water resource management. Traditionally, satellite altimeters were designed to monitor homogeneous surfaces such as oceans or ice sheets, resulting in a poor performance over small inland water bodies due to the contribution from land contamination in the returned waveforms. The advent of synthetic aperture radar (SAR) altimetry (with its improved along-track spatial resolution) has enabled the measurement of inland water levels with a better accuracy and an increased spatial resolution. This paper presents three specialized algorithms or retrackers to retrieve water levels from SAR altimeter data over inland water bodies dedicated to minimizing land contamination from the waveforms. The performances of the proposed waveform portion selection method with three retrackers, namely, the threshold retracker, Offset Centre of Gravity (OCOG) retracker and 2-step physical-based retracker, are compared. Time series of water levels are retrieved for water bodies in the Ebro River basin (Spain). The results show good agreement with in situ measurements from the Ebro Reservoir (width is approximately 1.8 km) and Ribarroja Reservoir (width is approximately 400 m) with un-biased root-mean-square errors (RMSEs) of approximately 0.28 m and 0.16 m, respectively. The performances of all three retrackers are also compared with the European Space Agency’s ocean retracker in the Sentinel-3 Level-2 product.
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Earth Sciences, Geoinformatics; R, Programming, Statistical Analysis, Mariana Trench, Bathymetry
Online: 16 November 2018 (11:00:48 CET)
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The study focuses on the application of R programming language towards marine geological research with a case study of Mariana Trench. Due to its logical and straightforward syntax, multi-functional standard libraries, R is especially attractive to the geologists for the scientific computing. Using R libraries, the unevenness of various factors affecting Mariana Trench geomorphic structure has been studied. These include sediment thickness, slope steepness, angle aspect, depth at the basement and magmatism of the nearby areas. Methods includes using following R libraries: {ggplot2} for regression analysis, Kernel density curves, compositional charts; {ggalt} for Dumbbell charts for data comparison by tectonic plates, ranking dot plots for correlation analysis; {vcd} for mosaic plots, silhouette plots for compositional similarities among the bathymetric profiles, association plots; {car} for ANOVA. Bathymetric GIS data processing was dome in QGIS and LaTeX. The innovativeness of the work consists in the multi-disciplinary approach combining GIS analysis and statistical methods of R which contributes towards studies of ocean trenches, aimed at geospatial analysis of big data.
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Stefan Kollet,
Fabian Gasper,
Slavko Brdar,
Klaus Goergen,
Harrie-Jan Hendricks-Franssen,
Jessica Keune,
Wolfgang Kurtz,
Volker Küll,
Florian Pappenberger,
Stefan Poll,
Silke Trömel,
Prabhakar Shrestha,
Clemens Simmer,
Mauro Sulis
Earth Sciences, Geoinformatics; terrestrial modeling; real-time forecasting/monitoring; workflows
Online: 16 November 2018 (08:06:18 CET)
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Operational weather and also flood forecasting has been performed successfully for decades and is of great socioeconomic importance. Up to now, forecast products focus on atmospheric variables, such as precipitation, air temperature and, in hydrology, on river discharge. Considering the full terrestrial system from groundwater across the land surface into the atmosphere, a number of important hydrologic variables are missing especially with regard to the shallow and deeper subsurface (e.g. groundwater), which are gaining considerable attention in the context of global change. In this study, we propose a terrestrial monitoring/forecasting system using the Terrestrial Systems Modeling Platform (TSMP) that predicts all essential states and fluxes of the terrestrial hydrologic and energy cycles from groundwater into the atmosphere. Closure of the terrestrial cycles provides a physically consistent picture of the terrestrial system in TSMP. TSMP has been implemented over a regional domain over North Rhine-Westphalia and a continental domain over European in a real-time forecast/monitoring workflow. Applying a real-time forecasting/monitoring workflow over both domains, experimental forecasts are being produced with different lead times since the beginning of 2016. Real-time forecast/monitoring products encompass all compartments of the terrestrial system including additional hydrologic variables, such as plant available soil water, groundwater table depth, and groundwater recharge and storage.
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Earth Sciences, Environmental Sciences; transitions; water management regimes; niches; visions; agency;
Online: 15 November 2018 (11:22:48 CET)
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This paper analyses six major transitions in watershed management in the Lower Mississippi River from the early 19th century till present. A conceptual framework is developed for analysing the role of visions, agency and niches in water management transitions and applied to a historical case on water management in the Lower Mississippi River. It is shown that water management regimes change over time and that major transitions were preceded by niches, in which new visions were developed and empowered. The case shows that: (i) emerging visions play an important role in guiding transitions; (ii) agency enables the further diffusion of visions and niches; (iii) vision champions play an important role in transitions, but are not decisive; (iv) each transition has led to an extension of the number of societal functions provided, which has led to more complex water management regimes in which functions are combined and integrated; and (v) external landscape factors are important, as they can lead to awareness and urgency in important decision making processes.
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Earth Sciences, Geophysics; Common Middle Point; Propagator; Spatial Reflector; small-scale heterogeneities; diffraction/scattering imaging; finite-difference simulation; local grid refinement in time and space.
Online: 15 November 2018 (11:18:18 CET)
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Computation of Common Middle Point seismic sections and their subsequent time migration and diffraction imaging provides very important knowledge about the internal structure of 3D heterogeneous geological media and are key elements for successive geological interpretation. Full-scale numerical simulation, that computes all single shot seismograms, provides a full understanding of how the features of the image reflect the properties of the subsurface prototype. Unfortunately, this kind of simulations of 3D seismic surveys for realistic geological media needs huge computer resources, especially for simulation of seismic waves’ propagation through multiscale media like cavernous fractured reservoirs. In order to significantly reduce the query of computer resources we propose to model these 3D seismic cubes directly rather than the shot-by-shot simulation with subsequent CMP stacking. To do that we modify the well known "exploding reflectors principle" for 3D heterogeneous multiscale media by use of the finite-difference technique on the base of grids locally refined in time and space. To be able to simulate realistic models and acquisition we develop scalable parallel software, which needs reasonable computational costs.
Numerical results for simulation of Common Middle Points sections and their time migration are presented and discussed.
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Earth Sciences, Environmental Sciences; Artificial Wetlands; Horizontal Wetland; Subsurface Flow
Online: 15 November 2018 (10:16:37 CET)
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The objective of this work is to evaluate the impact of the innovative modifications made to the conventional effluent capture and discharge devices used in subsurface flow wetlands (SSFW). The main modifications developed consist on extending the influence of the capture and discharge device in such a way that the SSFW width and height are fully covered. This improved innovative device was applied and evaluated in two subsurface flow wetlands, one on a pilot scale and one on a real scale. To evaluate the impact of the innovative device with respect to conventional one in the operational functioning of subsurface flow wetlands, the elimination of chemical oxygen demand was measured and compared. The results show that for the innovative device, the COD removal was 10% higher than for the conventional device, confirming the validity and effectiveness of the modifications implemented in the effluent capture and discharge devices used in SSFW.
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Earth Sciences, Other; Jason-2; Jason-3; glacier; Landsat; Mt. Tanggula; satellite altimeter; Tibet; TOPEX/Poseidon
Online: 15 November 2018 (06:03:39 CET)
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An oceanic radar altimeter such as TOPEX/Poseidon (T/P) is typically for observing elevation changes over the open oceans or large inland lakes/rivers, with limited applications over solid earth due to its large footprint and susceptibility to waveform contamination and slope effect. Here we demonstrate that it is possible to construct a long-term time series of glacier elevation change from T/P-series radar altimeters over two flat surfaces near a glacier terminus and an icefield (Sites A and B, with slopes of 2° and 0.8°) in Mt. Tanggula, Tibet, at elevations over 5400 m. We retracked radar waveforms using the subwaveform threshold algorithm, selected quality altimeter data (1/4 of the original) with nearly the same slope and adjusted the original elevations by fitting with a time-varying, 2nd order surface. The glacier elevation changes at the two sites from T/P (1993–2002) show seasonal elevation oscillations with linear rates at about −3 m/year and abnormal seasonal changes around the 1997–98 El Niño. Site A is over a deep valley in southern Tanggula. Its elevation dropped about 30 m over 1993–2002 (from T/P) and the glacier almost disappeared by 2016 (from altimeters and satellite images). Despite the sporadic Jason-2 and Jason-3 altimeter data, we also derived long-term rates of glacier elevation change over 1993–2017. Landsat-derived glacier area and elevation changes near the two sites confirm the rapid glacier thinning from the altimeters. The glacier meltwater near Site A supplied increasing source water to Chibuzhang Co west of Mt. Tanggula, contributing partially to its accelerated rising lake level. The glacier thinning at Site B (icefield) was correlated with the increased discharge of the Tuotuo River in eastern Mt. Tanggula, a source region of the Yangtze River. The successful detection of glacier thinning at the two sites shows that T/P-series altimeters can serve as a virtual station at a flat glacier spot to monitor long-term glacier elevation changes in connection to climate change. This virtual station concept is particularly useful for inaccessible glaciers, but its implementation faces two challenging issues: increasing the volume of quality altimeter data and improving the ranging accuracy over a targeted mountain glacier spot.
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Earth Sciences, Environmental Sciences; marine ecotourism; coastal areas; fishermen; development models; sustainable
Online: 15 November 2018 (05:51:15 CET)
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Coastal areas in the South Coast of West Java Province have the potential to develop marine ecotourism, one of which is the Pangandaran area which must be transferred into economic value by not damaging natural resources. Marine ecotourism development is not only intended to raise foreign exchange for local governments, but are also expected to play a role in maintaining natural resources sustainably. This research aims to analyze the sustainable synergistic marine ecotourism development model. The method used in this research using quantitative descriptive method. The Quantitative descriptive method is used to describe the general condition of the research area, using primary and secondary data. The technique of taking respondents using accidental sampling as many as 50 respondents consisting of tourists, public figures, fishermen who have side jobs as a provider of marine ecotourism services. The analysis tool used is through a Rapfish model approach to measuring the synergistic model of sustainable development of marine ecotourism. Based on the results of a research on a sustainable synergistic marine ecotourism development model by measuring the ecological dimensions of environmental services in high conditions, the economic dimension of marine ecotourism is in moderate condition. Marine ecotourism technology in low conditions and social dimensions of marine ecotourism in low conditions. Model development of sustainable marine ecotourism synergistic with regard to the dimension of environmental, economic and social institutions should be able to form integrated from infrastructure to support marine ecotourism up to raise the level of income of fishermen who have a second job as a marine ecotourism providers. The infrastructure and regulatory dimensions are recommended to use the technology information to promote marine ecotourism optimally and regulations need to make marine ecotourism zoning rules and infrastructure improvements.
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Earth Sciences, Atmospheric Science; damaged area; direct economic loss; disaster; drought; extreme precipitation
Online: 15 November 2018 (04:26:41 CET)
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Understanding the distribution in drought and floods plays an important role in disaster risk management. The present study aims to explore the trends in the standardized precipitation index and extreme precipitation days in China, as well as to estimate the economic losses they cause. We found that in the Northeast China, northern of North China and northeast of Northwest China were severely affected by drought disasters (average damaged areas were 6.44 million hectares) and the most severe drought trend was located in West China. However, in the north of East China and Central China, the northeastern of the Southwest China was severely affected by flood disasters (average damaged areas were 3.97 million hectares) and the extreme precipitation trend is increasing in the northeastern of the Southwest China. In the Yangtze River basin, there were increasing trends in terms of drought and extreme precipitation, especially in the northeastern of the Southwest China, where accompanied by severe disaster losses. By combining the trends in drought and extreme precipitation days with the distribution of damaged areas, we found that the increasing trend in droughts shifted gradually from north to south, especially in the Southwest China, and the increasing trend in extreme precipitation gradually shifted from south to north.
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Earth Sciences, Environmental Sciences; growth promotion; palm mat geotextile; physical property; sand fixation
Online: 14 November 2018 (10:17:54 CET)
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As the traditional sand fixation measures have many limitations, new sand fixing technologies and methods are urgently needed to be developed. This study demonstrated a new sand fixation method using palm mat geotextile to fix the sand dunes and plant grass. We experimented the physical property of the palm mat geotextile in the laboratory, and observed the vegetation growth in the Hobq Desert. The results showed that (1) The palm mat geotextile is more lighter and tougher than the common straw mat geotextile, the average weight, thickness and tensile strength of palm mat geotextile were 2023 g/m2, 20.14 mm, and 842–860 N/m, after a year of field observation, the tensile strength decreased by only 2%. (2) The palm mat geotextile had excellent water retention capacity and scouring resistance, the maximum water content reached 227%, and the substrate lost 2.9% after the simulation of heavy rainfall for 3 hours with rainfall intensity of 30 mm/h in laboratory. (3) The palm mat geotextile significantly decreased the soil temperature and increase the humidity in summer, the observed results shown that the palm mat geotextile had the greatest influence on 5cm depth of the soil temperature and 10cm depth of soil humidity. (4) The field experiment results showed that the vegetation coverage and the biomass of the palm mat geotextile with 2 m × 2 m were 35% and 11.21 g (3.9 times and 4.1 times than that of control group, 1.7 times and 1.8 times than that of high-banded salix psammophila sand-barriers group which is widely used in the Hobq Desert).
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Earth Sciences, Atmospheric Science; Thunderstorm electrification; Ice crystal-graupel collision; Relative growth rate theory; Temperature gradient; Non-thermal equilibrium; Tripole charge structure; Thunderclouds hydrometeors
Online: 13 November 2018 (15:14:58 CET)
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Thunderstorm electrification has been studied for hundreds of years. Several mechanisms have been proposed to elucidate the electrification, including convective charging, inductive precipitation charging, and ice crystal-graupel collision charging. Field observations and model studies have demonstrated the vital roles that graupel and ice crystals play in the electrification, but the mechanism of the collision charging is still unclear. The fundamental essence of relative growth rate theory used for explaining the tripole charge structure in thunderclouds also needs a further exploration. We analyze the processes of ice crystal-graupel collision charging from charge migration inside hydrometeors to charge separation between two hydrometeors. The driving effects of temperature gradient and chemical potential gradient in charge migration are clarified, as well as the applicability of the relative growth rate theory, thermoelectric effect and surface tension gradient in different humidities. Based on the understanding from these electrification mechanisms, we propose that the essence of charge separation is driven by non-thermal equilibrium, and future studies on thunderstorm electrification should focus on the dynamical non-thermal equilibrium of cloud particles.
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Earth Sciences, Environmental Sciences; coal; BTEX; hazardous air pollutants; domestic fuel burning
Online: 13 November 2018 (09:59:45 CET)
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A D-grade type coal was burned under simulated domestic practices in a controlled laboratory set-up, in order to characterize emissions of volatile organic compounds (VOCs); viz. benzene, toluene, ethylbenzene and xylenes (BTEX). Near-field concentrations were collected in a shack-like structure constructed using corrugated iron, simulating a traditional house found in informal settlements in South Africa. Measurements were carried out using the Synspec Spectras GC955 real-time monitor over a three-hour burn cycle. The 3-hour average concentrations (in µg/m3) of benzene, toluene, ethylbenzene, p-xylene and o-xylene were 919 ± 44, 2051 ± 91, 3838 ±19, 4245 41 and 3576 ± 49, respectively. The cancer risk for adult males and females in a typical SA household exposure scenario, was found to be 1.1 -1.2 and 110-120 folds higher than the US EPA designated risk severity indicator (1E-6), respectively. All four TEX compounds recorded the Hazard Quotient (HQ) of less than 1, indicating a low risk of developing related non-carcinogenic health effects. The HQ for TEX ranged from 0.001– 0.05, with toluene concentrations being the lowest and ethylbenzene the highest. This study has demonstrated that domestic coal burning may be a significant source of BTEX emission exposure.
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Earth Sciences, Environmental Sciences; light environment; artificial light; natural light; function distribution; optical parameter
Online: 13 November 2018 (04:38:06 CET)
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As the problem of light pollution becomes more serious, more and more scholars pay attention to this issue and carry out related research. In the perspective of cities, the measurements of light pollution mainly focus on the brightness of the sky or artificial lighting on the ground. However, there is lack of research on the whole urban space. With the two-dimensional brightness analyses, this paper processes the changes of the light environment of the whole urban space into image quantization. It gets the 3D and 2D light environment changes of luminance distribution, color temperature distribution and chromaticity in the three space layers, the ground layer, the urban canopy layer and the sky layer, from dusk with natural light to night with artificial lighting completely. It is found that the brightness difference between the light environments among the three city levels gradually reduces with the measuring time, and the final values maintain at 0.11~0.25 cd/m2. In the ground layer, the light environment is mainly affected by the lighting facilities, and vegetation can prevent the light from scattering up. The light environment of the urban canopy layer is the brightest in the whole city space and has the largest influence on the sky layer. The color concentrates in the range of yellow and red. The color temperature near the ground distributes in 3000K~15000K, and near the sky distributes in 2300K~2700K which is warmer than the natural night sky. The sky brightness of Dalian city is about 951 times than the natural night sky.
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Earth Sciences, Environmental Sciences; ecosystem services; valuation; monetization; assessment; mapping, biodiversity; geographic information technologies
Online: 12 November 2018 (11:51:07 CET)
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Putting value to ecosystem services is something that society still refuses or simply ignores because it is not aware of the benefits that ecosystems provide us. In fact, people should be aware that a good understanding of ecosystem services can lead to win-win situations. Being aware of the importance of preserving the ecosystem and attaching value to its services will enable the development of self-sustaining strategies and appropriate policies for better ecological governance. Decades of over exploitation of natural resources, introduction and spread of alien species and, also, climate change, forest fires among other threats, have fostered biodiversity loss. The European Union Biodiversity Strategy has as one of its main goals to stop biodiversity loss and the degradation of ecosystem services; if possible, to recover the most threatened and degraded ecosystems, based on 20 Actions divided into 6 Targets. The present work falls within the scope of Action 5 of Target 2 – Improve knowledge of ecosystems and their services in the EU. The specific focus of this study is the Site of Community importance “Dunas de Mira, Gândara and Gafanhas” (Portugal) and the assessment of its ecosystem services, in accordance with the methodology proposed by the MAES (Mapping and Assessment of Ecosystems and their Services) Working Group. The work currently under way, a small segment of which is presented here, aims to identify, map and, when possible, assign value to the ecosystem services. For this purpose, modern GIS technologies will be used. This approach was implemented using a combination of data and tasks, including the photo-interpretation of Sentinel 2 (COPERNICUS Program) satellite imagery. The data geoprocessing tasks and image segmentation were developed using QGIS software and IMPACT Toolbox software (developed by the Joint Research Center – JRC, of the European Union), respectively. The analysis of Land Use and Burned Areas maps for the SCI "Dunas de Mira, Gândara and Gafanhas" led us to conclude that Forests ecosystems, the most affected by the fire of October 2017, continue to have the greatest expression in the area under study even though they have lost more than 50% of the area, and their services were also the ones most affected by the fire.
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Earth Sciences, Environmental Sciences; tomato; biofumigation; organic; inorganic fertilizer; sustainability; environment
Online: 12 November 2018 (11:47:29 CET)
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Intensive greenhouse horticulture can cause various environmental problems. Among them, the management, storage and processing of crop residues can provoke aquifer contamination, pest proliferation, bad odors or the abuse of phytosanitary treatments. Biosolarization put in value any fresh plant residue and is an efficient technique for the control of soil-borne diseases. This study aims to examine an alternative means of managing greenhouse crop residues through biosolarization and to investigate the influence of organic matter on yield and quality of tomato (Solanum lycopersicum, L.) fruit. With this purpose, the following nutritional systems were evaluated: inorganic fertilization with and without brassica pellets (Fert, Fert + and Fert ++), fresh tomato plant debris with and without brassica pellets (Rest, Rest + and Rest ++) and no fertilizer application (Control). The addition of organic matter equaled all the treatments except for control with regard to yield and quality of the tomato fruit. In light of these results, the application of tomato plant debris to the soil through biosolarization is postulated as an alternative for the management of crop residues, solving an environmental problem and having a favorable impact on the production and quality of tomatoes as a commercial crop.
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Earth Sciences, Other; CAMELS; flood frequency; hydrological signatures; extreme value theory; random forests; spatial modelling
Online: 12 November 2018 (04:59:22 CET)
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The finding of important explanatory variables for the location parameter and the scale parameter of the generalized extreme value (GEV) distribution, when the latter is used for the modelling of annual streamflow maxima, is known to have reduced the uncertainties in inferences, as estimated through regional flood frequency analysis frameworks. However, important explanatory variables have not been found for the GEV shape parameter, despite its critical significance, which stems from the fact that it determines the behaviour of the upper tail of the distribution. Here we examine the nature of the shape parameter by revealing its relationships with basin attributes. We use a dataset that comprises information about daily streamflow and forcing, climatic indices, topographic, land cover, soil and geological characteristics of 591 basins with minimal human influence in the contiguous United States. We propose a framework that uses random forests and linear models to find (a) important predictor variables of the shape parameter and (b) an interpretable model with high predictive performance. The process of study comprises of assessing the predictive performance of the models, selecting a parsimonious predicting model and interpreting the results in an ad-hoc manner. The findings suggest that the shape parameter mostly depends on climatic indices, while the selected prediction model results in more than 20% higher accuracy in terms of RMSE compared to a naïve approach. The implications are important, since incorporating the regression model into regional flood frequency analysis frameworks can considerably reduce the predictive uncertainties.
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Earth Sciences, Environmental Sciences; hyper point cloud (HPC); HPC-based intensity surface; percentile height; gridding; full waveform LiDAR; tree segmentation; vegetation structure
Online: 8 November 2018 (14:56:35 CET)
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Full waveform (FW) LiDAR holds great potential for retrieving vegetation structure parameters at a high level of detail, but this prospect is constrained by practical factors such as lack of available handy processing tools and technical intricacy of waveform processing. This study introduces a new product, named the Hyper Point Cloud (HPC) derived from FW LiDAR data, and explore its potential applications such as tree crown delineation using the HPC-based intensity and percentile height (PH) surfaces, which show a promising solution to the constraints of using FW LiDAR data. Results of the HPC present a new direction to handle FW LiDAR data and offer prospects for studying the mid-story and understory of vegetation with high point density (~ 182 points/m2). The intensity-derived digital surface model (DSM) generated from the HPC shows that the ground region has larger maximum intensity (MAXI) and mean intensity (MI) than the vegetation region while having smaller total intensity (TI) and number of intensities (NI) at the given grid cell. Our analysis of intensity distribution contours at individual tree level exhibit similar patterns, indicating that the MAXI and MI are decreasing from the tree crown center to tree boundary while a rising trend is observed for TI and NI. These intensity variable contours provide a theoretical justification for using HPC-based intensity surfaces to segment tree crowns and exploit their potential for extracting tree attributes. The HPC-based intensity surfaces and the HPC-based PH Canopy Height Models (CHM) demonstrate promising tree segmentation results comparable to the LiDAR derived CHM for estimating tree attributes such as tree locations, crown widths and tree heights. We envision that products such as the HPC and the HPC-based intensity and height surfaces introduced in this study can open new perspectives to use FW LiDAR data and alleviate the technical barrier of exploring FW LiDAR data for detailed vegetation structure characterization.
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Earth Sciences, Atmospheric Science; Climate; land-atmosphere interaction; clouds; diurnal cycle; snow cover; Prairies; land-use; hydrometeorology
Online: 8 November 2018 (14:13:53 CET)
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Analysis of the hourly Canadian Prairie data for the past 60 years has transformed our quantitative understanding of land-atmosphere-cloud coupling. The key reason is that trained observers made hourly estimates of opaque cloud fraction that obscures the sun, moon or stars, following the same protocol for 60 years at all stations. These 24 daily estimates of opaque cloud data are of sufficient quality that they can be calibrated against Baseline Surface Radiation Network data to give the climatology of the daily short-wave, longwave and total cloud forcing (SWCF, LWCF and CF). This key radiative forcing has not been available previously for climate datasets. Net cloud radiative forcing reverses sign from negative in the warm season to positive in the cold season, when reflective snow reduces the negative SWCF below the positive LWCF. This in turn leads to a large climate discontinuity with snow cover, with a systematic cooling of 10°C or more with snow cover. In addition, snow cover transforms the coupling between cloud cover and the diurnal range of temperature. In the warm season, maximum temperature increases with decreasing cloud, while minimum temperature barely changes; while in the cold season with snow cover, maximum temperature decreases with decreasing cloud and minimum temperature decreases even more. In the warm season, the diurnal ranges of temperature, relative humidity, equivalent potential temperature and the pressure height of the lifting condensation level are all tightly coupled to opaque cloud cover. Given over 600 station-years of hourly data, we are able to extract, perhaps for the first time, the coupling between cloud forcing and the warm season imbalance of the diurnal cycle; which changes monotonically from a warming and drying under clear skies to a cooling and moistening under cloudy skies with precipitation. Because we have the daily cloud radiative forci, which is large, we are able to show that the memory of water storage anomalies, from precipitation and the snowpack, goes back many months. The spring climatology shows the memory of snowfall back through the entire winter, and the memory in summer goes back to the months of snowmelt. Lagged precipitation anomalies modify the thermodynamic coupling of the diurnal cycle to the cloud forcing, and shift the diurnal cycle of mixing ratio which has a double peak. The seasonal extraction of the surface total water storage is a large damping of the interannual variability of precipitation anomalies in the growing season. The large land-use change from summer fallow to intensive cropping, which peaked in the early 1990s, has led to a coupled climate response that has cooled and moistened the growing season, lowering cloud-base, increasing equivalent potential temperature, and increasing precipitation. We show a simplified energy balance of the Prairies during the growing season and its dependence on reflective cloud.
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Earth Sciences, Other; Hegenshan-Heihe suture zone; Permian A-type granite; granite petrogenesis; Hongyan Cu-polymetallic deposit; ore-forming fluids; post-collisional slab break-off
Online: 8 November 2018 (09:45:45 CET)
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In order to study the petrogenesis and tectonic setting of Permian A-type granites and their relationships with hydrothermal mineralization along the Hegenshan-Heihe suture zone (HHSZ) in northeastern China, we select the newly discovered Hongyan Cu-polymetallic deposit in the northeastern part of the HHSZ that develops three stages of mineralization associated with the Shanshenfu alkali-feldspar granite (SAFG). The zircon U-Pb dating and whole rock geochemistry suggest that the SAFG is a typical A-type granite formed in the Early Permian. The zircon Hf isotopes and trace elements suggest that the SAFG has high Ti-in-zircon temperature (721–990℃), high magmatic oxygen fugacity and largely positive εHf(t) (+6.0 to +9.9). Therefore, we propose that the SAFG was derived from the crustal assimilation and fractional crystallization of the charnockitized juvenile crust. The high oxygen fugacity favors the chalcophile elements (e.g., Cu, Au, Ag) of the source region enriched in the fluid phases after magmatic fractional crystallization, consequently facilitating subsequent hydrothermal mineralization, which is also consistent with the characteristics of ore-forming fluids that changed from the initial high temperature, high salinity, high fO2 and CO2-rich magmatic-hydrothermal fluids of stage I to CO2-poor, dilute, and cooling meteoric fluids of stage III. Combined with regional geological background, the Permian A2-type granites along the HHSZ can be formed in post-collisional slab break-off process. In subsequent exploration for hydrothermal deposits along the HHSZ, the Permian A-type granites with arc-related juvenile crustal source and high fO2 have great potential and need more attention.
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Earth Sciences, Atmospheric Science; mixing layer; urban area; ceilometer; radiosonde
Online: 8 November 2018 (04:31:23 CET)
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Mixing layer height (MLH) is a crucial parameter for air quality modelling that is still not routinely measured. Common methods for MLH determination use atmospheric profiles recorded by radiosonde but they suffer from course temporal resolution since balloon launching is only twice a day. Recently cheap ceilometers are gaining popularity in the retrieval of MLH diurnal evolution based on aerosol profiles. This study presents a comparison of a proprietary (Jenoptik) and a free available (STRAT) algorithms to retrieve MLH diurnal cycle. The comparison is accomplished in summer season over urban area and radiosonde data is used to estimate MLHs according to parcel, lapse rate, and Richardson methods (the last algorithm is used as a reference in the study) in addition. It was found that STRAT and Jenoptik give lower MLH than radiosonde with an underestimation of about 150m and 650m respectively. Additionally, STRAT showed reasonable performance in tracking of MLH diurnal evolution. Daily MLH maximum of about 2000m was found in the late afternoon (18-19 LT). In contrast, Jenoptik algorithm showed more weaknesses, mainly attributed to its real-time operation and independent processing of a single profile. At night and during morning transition period, both lidar-based methods showed difficulties as MLH was often in the ceilometer’s incomplete overlapping zone so residual or advected aerosol layers aloft were misleadingly reported as mixing layer (ML).
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Earth Sciences, Environmental Sciences; El Nino Southern Oscillation; ENSO, El Nino extreme events;
Online: 7 November 2018 (16:30:41 CET)
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Observed ENSO statistics exhibits a non-gaussian behavior, which is indicative of the presence of nonlinear processes. In this paper we use the Recharge Oscillator model (ROM), a largely used Low-Order Model (LOM) of ENSO, as well as methodologies borrowed from the field of statistical mechanics to identify which aspects of the system may give rise to nonlinearities that are consistent with the observed ENSO statistics. In particular, we are interested in understanding whether the nonlinearities reside in the system dynamics or in the fast atmospheric forcing. Our results indicate that one important dynamical nonlinearity often introduced in the ROM cannot justify a non-gaussian system behavior, while the nonlinearity in the atmospheric forcing can instead produce a statistics similar to the observed. The implications of the non-Gaussian character of ENSO statistics for the frequency of extreme El Nino events is then examined.
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Earth Sciences, Geology; High-spatial-resolution images; Geology; Deep learning; Remote sensing
Online: 7 November 2018 (13:17:40 CET)
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Geologists employ high-spatial-resolution (HR) remote sensing (RS) data for many diverse applications as they effectively reflect detailed geological information, enabling high-quality and efficient geological surveys. Applications of HR RS data to geological and related fields have grown recently. By analyzing these applications, we can better understand the results of previous studies and more effectively use the latest data and methods to efficiently extract key geological information. HR optical remote sensing data are widely used in geological hazard assessment, seismic monitoring, mineral exploitation, glacier monitoring, and mineral information extraction due to high accuracy and clear object features. Compared with optical satellite images, synthetic-aperture radar (SAR) images are stereoscopic and exhibit clear relief, strong performance, and good detection of terrain, landforms, and other information. SAR images have been applied to seismic mechanism research, volcanic monitoring, topographic deformation, and fault analysis. Furthermore, a multi-standard maturity analysis of the geological applications of HR images using literature from the Science Citation Index reveals that optical remote sensing data are superior to radar data for mining, geological disaster, lithologic, and volcanic applications, but inferior for earthquake, glacial, and fault applications. Therefore, geological remote sensing research needs to be truly multidisciplinary or interdisciplinary, ensuring more detailed and efficient surveys through cross-linking with other disciplines. Moreover, the recent application of deep learning technology to remote sensing data extraction has improved automatic processing and data analysis capabilities.
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Earth Sciences, Other; Disaster Risk Reduction; EO4SD; Official Development Assistance; Actionable Information; World Bank; International Financial Institutions
Online: 7 November 2018 (09:53:46 CET)
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Disaster Risk Reduction (DRR) is a high priority on the agenda of main stakeholders involved in sustainable development and Earth Observation (EO) can provide useful, timely and economical information in this context. This short communication outlines the European Space Agency’s (ESA) specific initiative to promote the use and uptake of satellite data in the global development community: ‘Earth Observation for Sustainable Development (EO4SD)’. One activity area under EO4SD is devoted to Disaster Risk Reduction: EO4SD DRR. Within this project, a team of European companies and institutions are tasked to develop EO services for supporting the implementation of DRR in International Financial Institutions’ (IFI) projects. Integration of satellite-borne data and ancillary data to generate insight and actionable information is thereby considered a key factor for improved decision making. To understand and fully account for the essential user requirements (IFI & Client States), engagement with technical leaders is crucial. Fit-for-purpose use of data and comprehensive capacity building eventually ensure scalability and long-term transferability. Future perspectives of EO4SD and DRR regarding mainstreaming are also highlighted.
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Earth Sciences, Atmospheric Science; Agro-economic crop water productivity; Hydro-economic modeling; CSPSO-MODSIM; Economic benefits; Crop pattern planning; Crop water Irrigation depth; Climate change; Iran.
Online: 5 November 2018 (11:12:25 CET)
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For water-stressed regions like Iran improving the effectiveness and productivity of agricultural water-use is of utmost importance due to climate change and unsustainable demands. Therefore, a hydro-economic model has been developed here for the Zarrine River Basin with the central concept of that demands are value-sensitive functions, where quantities of water-uses at different locations and times have a changeable economic benefits. To do this, the potential crop yields and the surface and groundwater resources, especially Boukan Dam inflow are simulated using the hydrologic model, SWAT, based on predicted climatic scenarios i.e. quantile mapping-downscaled projections. Then, to allocate the agricultural water based on the agro- economic crop water productivity (AEWP) of crops, a basin-wide water management tool, MODSIM, is customized. Next, a simulation- optimization model has been developed using a coupled CSPSO-MODSIM, to optimize the total AEWP, considering climatic impact and crop pattern scenarios, for 2020-2038, 2050-2068 and 2080-2098 periods. Finally, the optimum crop pattern and crop water irrigation depths are presented for different RCPs and periods. The results indicated that this approach will improve considerably the AEWPs and decrease the agricultural water-use up to 40%. Thus, this integrated model is able to support water authorities and other stakeholder in a water-scarce basin, as is the study area.
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Earth Sciences, Geology; landslide scars; canyon; fault escarpments; contourite deposits; digital elevation model; continental slope
Online: 5 November 2018 (04:06:37 CET)
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The acquisition of high resolution morpho-bathymetric data on the Calabro Tyrrhenian continental margin (Southern Italy) enabled us to identify several mass-wasting processes, including shallow gullies, shelf-indenting canyons and landslides. In particular, we focus our attention on submarine landslides occurring from the coast down to -1700 m, with mobilized volumes ranging from some hundreds up to tens of millions of cubic meters. These landslides also show a large variability of geomorphic features in the headwall, translational and toe domain. Based on their morphology and distribution, four main classes of coastal/submarine landslides have been recognized: a) rocky coastal/shallow-water failures characterized by large hummocky deposits offshore; b) large-size and isolated scars with associated landslide deposits, mostly occurring on open slope environment and lower part of tectonically-controlled escarpments; c) a linear array of coalescent and nested landslide scars occurring in the upper part of tectonically-controlled escarpments and canyon flanks; d) a cauliflower array of small and coalescent scars occurring in canyon headwall. The latter two classes of landslides are also characterized by a marked retrogressive evolution and their landslide deposits are generally not recognizable on the morpho-bathymetric data. By integrating the morpho-bathymetric dataset with the results of previous studies, we also discuss the main factors controlling the variability in size and morphology of these submarine landslides to provide insights on their failure and post-failure behavior.
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Earth Sciences, Geology; Moderate halophile; Carbonate minerals; Mg/Ca ratios; Different magnesium, Carbonic anhydrase; pH increase; Cell density; Growth mode
Online: 2 November 2018 (14:23:37 CET)
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Carbonate precipitation induced by microorganism has become a hot spot in the field of carbonate sedimentology, while the effect of different magnesium on biominerals has rarely been studied. Therefore, magnesium sulfate and magnesium chloride were used to investigate the significant role played on carbonate minerals. In this study, Staphylococcus epidermidis Y2 was isolated and identified by 16S rDNA homology comparison. The ammonia, pH, carbonic anhydrase, carbonate and bicarbonate ions were investigated. The mineral phase, morphology and elemental composition were analyzed by XRD and SEM-EDS. The ultrathin slices of bacteria were analyzed by HRTEM-SAED and STEM. The result showed that this bacterium could release ammonia and carbonic anhydrase to increase pH, and elevate the supersaturation via a large number of carbonate and bicarbonate ions released through carbon dioxide hydration catalyzed by carbonic anhydrase. The crystal cell density of monohydrocalcite was lower in magnesium chloride medium than that in magnesium sulfate medium. The crystal grew in a mode of spiral staircas in magnesium sulfate medium, while in a concentric circular pattern in magnesium chloride medium. There was no obvious intracellular biomineralization. This study may be helpful to further understand the biomineralization mechanism, may also provide some references for the reconstruction of paleogeological environment.
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Earth Sciences, Geophysics; finite-difference algorithm; magnetotelluric; 2D structures; modeling
Online: 2 November 2018 (14:03:46 CET)
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A finite-difference approach with non-uniform meshes was presented for simulating magnetotelluric responses in 2D structures. We presented the formulation of this scheme and gave some sights into its successful implementation, and compared finite-difference solution with known numerical results and simple analytical solutions. First, a homogeneous half-space model was tested and the finite-difference approach can provide very good accuracy for 2D magnetotelluric modeling. Then we compared to the analytical solutions for the two-layered model, the relative errors of the apparent resistivity and the impedance phase were both increased when the frequency was increased. In the end, we compare our finite-difference simulation results with COMMEMI 2D-0 model with the finite-element solutions. Both results are in close agreement to each other. These comparisons confirm the validity and reliability of our finite-difference algorithm.
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Earth Sciences, Oceanography; geostationary ocean color imager (GOCI); ocean color; diurnal dynamics; diurnal variability; uncertainties
Online: 2 November 2018 (09:50:37 CET)
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Short-term (hours) biological and biogeochemical processes cannot be fully captured by the current suite of polar-orbiting satellite ocean color sensors, as their temporal resolution is limited to potentially one clear image per day. Geostationary sensors, such as the Geostationary Ocean Color Imager (GOCI) from the Republic of Korea, allow the study of these short-term processes because their geostationary orbits permit the collection of multiple images throughout each day. To assess the capability to detect changes in water properties caused by these processes, however, requires an understaning of the uncertainties introduced by the instrument and/or geophysical retrieval algorithms. This work presents a study of the variability during the day over a water region of low-productivity with the assumption that only small changes in the water properties occur during the day over the area of study. The complete GOCI mission data were processed using the SeaDAS/l2gen package. Filtering criteria were applied to assure the quality of the data. Relative differences with respect to the midday value were calculated for each hourly observation of the day. Also, the influence of the solar zenith angle in the retrieval of remote sensing reflectances and derived products was analyzed. We determined that the uncertainties in water-leaving “remote-sensing” reflectance ($R_\text{rs}$) for the 412, 443, 490, 555, 660 and 680 nm bands on GOCI are 8.05$\times10^{-4}$, 5.49$\times10^{-4}$, 4.48$\times10^{-4}$, 2.51$\times10^{-4}$, 8.83$\times10^{-5}$, and 1.36$\times10^{-4}$ sr$^{-1}$, respectively, and 1.09$\times10^{-2}$ mg m$^{-3}$ for the chlorophyll-a concentration (Chl-{\it a}), 2.09$\times10^{-3}$ m$^{-1}$ for the absorption coefficient of chromophoric dissolved organic matter at 412 nm ($a_{\text{g}}(412)$), and 3.7 mg m$^{-3}$ for particulate organic carbon (POC). We consider these to be the floor values for detectable changes in the water properties due to biological, physical or chemical processes.
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Earth Sciences, Environmental Sciences; Risk attitude, farmers, multiple price list, climate change.
Online: 31 October 2018 (08:24:07 CET)
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Risk attitudes are relevant factors affecting the production and investment decisions at farm level. They are key factors that are related to farmers’ attitudes towards environment and climate change. Several methodological approaches are available to measure the level of stated risk of an economic agent. The Multiple Price List (MPL) method is one of the methods that is gaining relevance. In this study we apply the MPL and relate the risk outcomes with farmers’ characteristics and their perception towards environment and climate change. Data was collected using a face to face survey carried out for a group of 370 agricultural producers of the irrigation district located in northwest of Mexico. Results showed an average risk of about 0.32, locating the agricultural producers of the region in a group with risk aversion, according to the MPL scale. The heterogeneity analysis showed that the socioeconomic factors and the perceptions towards climate change are related to the farmers´ stated risk level. Farmers who are young women with propensity to use public support to invest were shown to be greater risk lovers. Farmers in the region have perceived climate change to a greater extent like floods, hail, diseases and pests, and changing vegetation.
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Earth Sciences, Atmospheric Science; developing thunderstorms, convective initialization, virtual brightness temperature fluxes, normalized updraft strength.
Online: 30 October 2018 (14:46:33 CET)
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This study presents a novel approach for the early detection of developing thunderstorms. To date, methods for the detection of developing thunderstorms usually rely on accurate atmospheric motion vectors (AMVs) for the estimation of cooling rate of convective clouds, which corresponds to the updraft strength of the cloud objects. In this study we present a method for the estimation of the updraft strength that does not rely on AMVs. The updraft strength is derived directly from the satellite observations in the SEVIRI water vapor channels. For this purpose the absolute value of the vector product of two vectors derived from the observed radiances emitted by the water vapor channels in 2 subsequent satellite images is calculated. The x and y components of the vectors consists of the temporal change of the spatial brightness temperature gradients in x- and y-direction, the z component consists of the temporal variation of the brightness temperature at pixel level. The absolute value of the vector product is referred to as normalized updraft strength (NUS). The performance of the method has been investigated for 2 summer periods in 2016 and 2017 by validation with lightning data. Values of the Critical Success Index (CSI) of about 66 % for the 2016 period and 62 % for the 2017 period demonstrate the good performance of the method. The POD values for the experiments with the highest CSI values are 90.3 for 2016 period and 87.6 for the 2017 period, respectively The corresponding FAR values are 28.2% (2016) and 32.5 % (2017), respectively. In summary, the method has the potential to reduce the forecast lead time significantly, and can be quite useful in regions without a well maintained radar network.
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Earth Sciences, Environmental Sciences; carbon; energy; campus; sustainability; city; low carbon
Online: 30 October 2018 (08:53:17 CET)
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The establishment of low carbon assessment initiatives is a crucial task especially at the city level. The determination of which source of carbon contributed more require robust data set and strategic approach. Hence, by using the campus as a small city approach, the establishment of carbon assessment and its’ reduction initiatives was required to keep track of the hotspot of the carbon source. The substantial amount of carbon source from campus operations such as energy consumption in the building, waste generation, and water consumption were identified. Moreover, as institutions of higher education, the execution of low carbon campus was initiated structurally involves the triangulation of research activities, teaching & learning and as well as campus operations or known as campus living lab approach. The application of low carbon cities framework, LCCF and assessment system enables to strategize the low carbon campus initiatives through the use of carbon footprint concept and the LCCF carbon track.
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Earth Sciences, Oceanography; Western South Atlantic continental margin; benthic Foraminifera; fresh water; nutrients; eutrophication; anoxic
Online: 30 October 2018 (08:51:08 CET)
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The present work focuses on fresh water signatures at the sediment-water interface (1 cm) using foraminiferal species in both austral winter and summer in eleven longitudinal transects on the Western South Atlantic continental margin between 27° and 37° S, at water depths of 11.7 to 250 m. Here we show that depth, salinity, temperature, oxygen, grain size (mud and sand percentage), suspended matter, organic matter, SiO4, NO2, and NO3 in this order of importance are responsible for the distribution of foraminiferal species and thecamoebians. The presence of these microfossils indicate freshwater influx in four sectors over the continental shelf: Itajaí-Açu River, Laguna estuarine system, Patos Lagoon and RdlP (Rio de la Plata) will be explored further in detail. Our findings on freshwater signature on the continental shelf sediments through benthic species indicator are comparable to other continental systems worldwide, and a paleo record study would be useful for three South American countries (Brazil, Argentina and Uruguay). A freshwater signature in the continental shelf indicates deposition sites probably linked to anthropogenic impact since most of the pollutants and contaminants are dumped into water bodies that eventually reach and accumulate in the ocean. Therefore, the freshwater-related species on the continental shelf reflects exactly where the depositional sediment sites are, and where anthropogenic impacts accumulate. Foraminiferal microhabitat occupation within these zones is discussed in detail. And we conclude that together with the fauna, the abiotic parameters play an important role in determining the occurrence and degree of marine eutrophication induced by the input of polluted river waters, also showing possible anoxic environments on the shelf.
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Earth Sciences, Oceanography; Estuarine Modeling; Lateral Circulation; Tidal Currents; Momentum Balance
Online: 30 October 2018 (08:49:57 CET)
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Using a three-dimensional, hydrostatic, primitive-equation ocean model, this study investigates the dynamics of lateral circulation in a partially stratified tidal inlet, the Barataria Pass in the Gulf of Mexico, over a 25.6-hour diurnal tidal cycle. Model performance is assessed against observational data. During flood tide, the lateral circulation exhibits the characteristics similar to that induced by differential advection, i.e., lateral flow consists of two counter-rotating cells and is convergent at the surface. The analysis of momentum balance indicates that, in addition to the pressure gradient and vertical stress divergence, nonlinear advection and horizontal stress divergence are also important contributors. During ebb phase, the lateral circulation is mostly eastward for the whole water column and persisting for almost the whole period. The surface divergence suggested by the differential advection mechanism lasts for a very short period, if it ever exists. The main momentum balance across most of the transect during ebb is between the along-channel advection of cross-channel momentum and pressure gradient. The sectional averaged lateral velocity magnitude during ebb is comparable to that during flood, which is different from the idealized numerical experiment result.
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Earth Sciences, Environmental Sciences; geoecological situations; permafrost zone; cryolithozone; cryogenic processes; landscapes stability; geoinformation mapping
Online: 30 October 2018 (05:19:47 CET)
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The diagnostics of natural landscapes geoecological state in the course of the permafrost zone economic development should be based on the assessment of the destructive cryogenic processes formation. It is expedient to consider it in terms of landscapes resistance to cryogenic processes increase. The choice of lithocryogenic stability parameters is substantiated. These are: permafrost distribution over the area, its annual mean temperature and ice content, protective properties of the vegetation and etc. Cryogenic processes activation is estimated with regard to their area, development rate and attenuation, natural landscapes damage, hazard for engineering facilities operation. The assessment procedure, and the way of improving expert numerical scores are shown. At Geography Faculty of Lomonosov Moscow State University, the authors have developed a number of the approved methods of making evaluation maps of different scales applying the methods of landscape indication, modern methods of space images decoding, methods of expert scores, the method statistical calculations and methods of spatial GIS-analysis. The technique of Atlas geo-information mapping on the landscape basis has been introduced in seven atlases at scales from 1:3 000 000 to 1:20 000 000. These maps are widely used in design and survey organizations and in education.
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Earth Sciences, Geoinformatics; Urban Remote Sensing; Sentinel-1; Landsat 8; Built-Up; Data Fusion; Texture; Africa
Online: 29 October 2018 (16:02:53 CET)
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The rapid urbanization that takes place in developing regions such as Sub-Saharan Africa is associated with a large range of environmental and social issues. In this context, remote sensing is essential to provide accurate and up-to-date spatial information to support risk assessment and decision making. However, mapping urban areas remains a challenge because of their heterogeneity, especially in developing regions where the highest rates of misclassification are observed. Nevertheless, urban areas located in arid climates --- which are among the most vulnerables to anthropogenic impacts, suffer from the spectral confusion occurring between built-up and bare soil areas when using optical imagery. Today, the increasing availability of satellite imagery from multiple sensors allow to tackle the aforementioned issues by combining optical data with Synthetic Aperture Radar (SAR). In this paper, we assess the complementarity of the Landsat 8 and Sentinel-1 sensors to map built-up areas in twelve Sub-Saharan African urban areas, using a pixel-level supervised classification based on the Random Forest classifier. We make use of textural information extracted from SAR backscattering data in order to reduce the speckle noise and to introduce contextual information at the pixel level. Results suggest that combining both optical and SAR features consistently improves classification performances, mainly by enhancing the differentiation between built-up and bare lands. However, the fusion was less beneficial in mountainous case studies, suggesting that including features derived from a Digital Elevation Model (DEM) could improve the reliability of the proposed approach. As suggested by previous studies, combining features computed from both VV and VH polarizations consistently led to better classification performances. On the contrary, introducing textures computed from different spatial scales did not improve the classification performances.
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Earth Sciences, Environmental Sciences; Chemical sensors; E-nose; Environmental monitoring; Seawater; Sensors; Volatile Organic Compounds
Online: 29 October 2018 (14:36:11 CET)
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Electronic Nose (eNose) systems are particularly appreciated for their portability, usability, relative low cost and real-time or near real-time response. Their application finds space in several domains, including environmental monitoring. Within this field, marine monitoring is of particular scientific relevance due to the fragility of this specific environment, daily threatened by human activities that can potentially bring to catastrophic and irreversible consequences on marine wildlife. Under such considerations, a systematic review, complying with the PRISMA guidelines, was conducted covering the period up to October 15, 2018, in PubMed, ScienceDirect and Google Scholar. Despite the relatively low number of articles published on this specific topic and the heterogeneity of the technological approaches employed, the results obtained by the various groups highlight the positive contribution eNose has given and can provide in near future for the monitoring and safeguarding of this delicate environment.
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Earth Sciences, Atmospheric Science; lidar, atmosphere, DIAL, optical parametric oscillator, trace gases
Online: 29 October 2018 (14:22:24 CET)
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Data on the atmospheric gas concentrations can be received with high efficiency and on a large spatial scale only from remote laser sounding instruments. The remote laser techniques with the use of lidars are widely used in the study of the atmosphere and control of its state. The aims of this work are the design and test in numerical and field experiments of a DIAL OPO lidar system based on KTA and KTP crystals for gas analysis of the atmosphere. Lidar measurements of atmospheric gases in the near/mid infrared region have been numerically simulated. The differential absorption lidar system based on optical parametric oscillators with nonlinear KTA and KTP crystals which allow laser radiation tuning both in the near and in the middle IR spectral region is described; it allows tuning laser radiation in the near/mid-IR wavelength regions. Lidar echo signals have been experimentally recorded in the 1.8–2.5 and 3–4 m wavelength ranges. The results of H2O and CO2 profile measurements along the surface sounding path are presented.
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Earth Sciences, Atmospheric Science; Thermal updraft velocity; Thermal convection; Soaring; Atmospheric Boundary Layer; Soaring birds; Sailplane; Aviation safety.
Online: 29 October 2018 (13:10:05 CET)
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A forecasting scheme of the thermal updraft velocity based on a theoretical model and data collected from flights records at gliding competitions, is presented. The forecasting scheme was based on the hypothesis that there is linear relationship between the overheat function at ground surface and the temperature difference between soil and air. The proportionality factor of this relationship was determined experimentally using observations recorded during gliding flights. The results showed that based on this simple scheme forecasting thermal convection is possible at any geographical location.
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Earth Sciences, Atmospheric Science; deep learning; convolutional neural networks; polar mesocyclones; satellite data processing; pattern recognition
Online: 29 October 2018 (10:16:49 CET)
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Polar mesocyclones (MCs) are small marine atmospheric vortices. The class of intense MCs, called polar lows, are accompanied by extremely strong surface winds and heat fluxes and thus largely influencing deep ocean water formation in the polar regions. Accurate detection of polar mesocyclones in high-resolution satellite data, while challenging, is a time-consuming task, when performed manually. Existing algorithms for the automatic detection of polar mesocyclones are based on the conventional analysis of patterns of cloudiness and involve different empirically defined thresholds of geophysical variables. As a result, various detection methods typically reveal very different results when applied to a single dataset. We develop a conceptually novel approach for the detection of MCs based on the use of deep convolutional neural networks (DCNNs). As a first step, we demonstrate that DCNN model is capable of performing binary classification of 500x500km patches of satellite images regarding MC patterns presence in it. The training dataset is based on the reference database of MCs manually tracked in the Southern Hemisphere from satellite mosaics. We use a subset of this database with MC diameters falling in the range of 200-400 km. This dataset is further used for testing several different DCNN setups, specifically, DCNN built “from scratch”, DCNN based on VGG16 pre-trained weights also engaging the Transfer Learning technique, and DCNN based on VGG16 with Fine Tuning technique. Each of these networks is further applied to both infrared (IR) and a combination of infrared and water vapor (IR+WV) satellite imagery. The best skills (97% in terms of the binary classification accuracy score) is achieved with the model that averages the estimates of the ensemble of different DCNNs. The algorithm can be further extended to the automatic identification and tracking numerical scheme and applied to other atmospheric phenomena characterized by a distinct signature in satellite imagery.
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Earth Sciences, Environmental Sciences; TRMM; HEC-HMS; HEC-RAS;GIS; hydrological model; hydraulic model; flood; Chitral River Basin
Online: 29 October 2018 (04:28:08 CET)
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Flash flooding, a hazard which is triggered by heavy rainfall is a major concern in many regions of the world often with devastating results in mountainous elevated regions. We adapted remote sensing modelling methods to analyse one flood in July 2015, and believe the process can be applicable to other regions in the world. The isolated thunderstorm rainfall occurred in the Chitral River Basin (CRB), which is fed by melting glaciers and snow from the highly elevated Hindu Kush Mountains (Tirick Mir peak’s elevation is 7708 m). The devastating cascade, or domino effect, resulted in a flash flood which destroyed many houses, roads, and bridges and washed out agricultural land. CRB had experienced devastating flood events in the past, but there was no hydraulic modelling and mapping zones available for the entire CRB region. That is why modelling analyses and predictions are important for disaster mitigation activities. For this flash flood event, we developed an integrated methodology for a regional scale flood model that integrates the Tropical Rainfall Measuring Mission (TRMM) satellite, Geographic Information System (GIS), hydrological (HEC-HMS) and hydraulic (HEC-RAS) modelling tools. We collected and use driver discharge and flood depth observation data for five river sub-stream areas, which were acquired in cooperation with the Aga Khan Rural Support Program (AKRSP) organization. This data was used for the model’s calibration and verification. This modelling methodology is applicable for other regional studies especially for rough mountainous areas which lack local observations and river discharge gauges. The results of flood modelling are useful for the development of a regional early flood warning system and flood mitigation in hazardous flood risk areas. The flood simulations and prepared connected video visualization can be used for local communities. This approach is applicable for flood mitigation strategies in other regions.
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Earth Sciences, Geochemistry & Petrology; zircon; xenocryst; alkali basalt; Ratanakiri Volcanic Province; trace elements; O- and Hf-isotopes; U-Pb; (U-Th)/He
Online: 29 October 2018 (04:17:53 CET)
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Zircon xenocrysts from alkali basalts in Ratanakiri Province, Cambodia, represent a unique low-Hf zircon, within a 12,000 km long Indo-Pacific megacryst zone. Colourless, yellow, brown and red crystals ({100}, {101}, subordinate {211}, {1103}), with hopper growth and corrosion features, range up to 20 cm in size. Zircon chemistry implicates juvenile, Zr-saturated, mantle-derived alkaline melt (Hf 0.6–0.7 wt%, Y <0.2 wt%, U+Th+REE <600 ppm, Zr/Hf 66–92, Eu/Eu*N ~ 1, positive Ce/Ce*N, HREE enrichment). Incompatible element depletion with increasing Yb/SmN from core to rim at ~ constant Hf suggests single stage growth. Ti-in-zircon temperatures (~570–740 °C) are lower than predicted by crystal morphology (800–900 °C) and decrease from core to rim (DT = 10–50 °C). The d18O values (4.88 to 5.01‰ VSMOW) are relatively low for xenocrysts from the zircon Indo-Pacific zone (ZIP). The 176Hf/177Hf values (+ εHf 4.5–10.2) give TDepleted Mantle model source ages of 260–462 Ma and TCrustal ages of 391–754 Ma. The source magmas reflect variably depleted lithospheric mantle with little supracrustal input. Zircon U-Pb (0.88–1.56 Ma) and (U-Th)/He (0.86–1.02 Ma) ages are older than host basalt ages (~0.7 Ma), suggesting limited residence before transport. Zircon genesis suggests Zr-saturated, Al-undersaturated, carbonatitic-influenced, low-degree partial melting (<1%) of peridotitic mantle at ~60 km beneath the Indochina terrane.
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Earth Sciences, Other; overland flow, satellite altimetry, hydrological modelling, data assimilation
Online: 27 October 2018 (21:08:48 CEST)
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The Surface Water and Ocean Topography (SWOT) mission, to be launched in 2021, will provide water surface elevations, slopes, and river width measurements for rivers wider than 100 m. In this study, synthetic SWOT data are assimilated in a regional hydrometeorological model in order to improve the dynamics of continental waters over the Garonne catchment, one of the major French catchments. The aim of this paper is to demonstrate that the sequential assimilation of SWOT-like river depths allows the correction of river bed roughness coefficients and thus simulated river depths. An extended Kalman Filter is implemented and the data assimilation strategy was applied to four experiments of gradually increasing complexity regarding observation and model error over the 1995-2000 period. With respect to a “true” river state, assimilating river depths allows the proper retrieval of constant and spatially distributed roughness coefficients with a root mean square error of 1 m1/3 s-1, and the estimation of associated river depths. It was also shown that river depth differences can be assimilated, resulting in a higher root mean square error for roughness coefficients with respect to the true river state. The last study shows how one can take into account more realistic sources of SWOT error measurements, in particular the importance of the estimation of the tropospheric water content in the process.
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Earth Sciences, Geology; Organic Matter; TOC; Global Sensitivity Analysis; Modelling; Paris Basin, Toarcian
Online: 26 October 2018 (16:47:28 CEST)
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The active debate about the processes governing the organic-rich sediment deposition generally involves the relative roles of elevated primary productivity and enhanced preservation related to anoxia. However, other less spotlighted factors could have a strong impact on such deposits: e.g. residence time into the water column (bathymetry), sedimentation rate, transport behavior of organo-mineral floccules on the sea floor. They are all strongly interrelated and may be obscured in the current conceptual models inspired from most representative modern analogues (i.e. upwelling zones and stratified basins). To improve our comprehension of organic matter distribution and heterogeneities, we conducted a sensitivity analysis on the processes involved in organic matter production and preservation which have been simulated within a 3D stratigraphic forward model. The Lower-Middle Toarcian of the Paris Basin was chosen as a case study as it represents one of the best documented example of marine organic matter accumulation. The relative influence of the critical parameters (bathymetry, diffusive transport, oxygen mixing rate and primary production) on the output parameters (Total Organic Carbon, and oxygen level), determined performing a Global Sensitivity Analysis, shows that, in the context of a shallow epicontinental basin, a moderate primary productivity (> 175 gC.m-².yr-1) can led to local anoxia and organic matter accumulation. We argue that, regarding all the processes involved, the presence and distribution of organic-rich intervals is linked as a first-order parameter to the morphology of the basin (e.g. ramp slope, bottom topography). These interpretations are supported by very specific ranges of critical parameters which allowed to obtain output parameter values in accordance with the data. This quantitative approach and its conclusions open new perspectives about the understanding of global distribution and preservation of organic-rich sediments.
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Earth Sciences, Environmental Sciences; Nitrogen Fixation, Nitrous Oxide, Denitrification, Nitrogen Cycle, 15N2-labelling, Stable Nitrogen Isotopes.
Online: 26 October 2018 (16:02:24 CEST)
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Nitrogen (N) is an essential nutrient and plays an important role in plant growth and physiology. In addition, N is also the limiting nutrient in most terrestrial ecosystems. The increasing use of N fertilizers increases agricultural production, but also has negative impacts on biodiversity, water quality and increases emissions of greenhouse gases such as nitrogen oxides (NOx) and nitrous oxide (N2O) into the atmosphere. N2O is a strong greenhouse gas and the product of microbial transformation processes of N introduced into soil and groundwater (nitrification and denitrification). The production of N2O in soils is highly dependent on oxygen and water content, soil temperature and texture and the available amount of reactive nitrogen (NO3- or NH4+). In agricultural soils, N2O emissions are also influenced by the type of fertilizer used, crops grown, soil pH and NO3- concentration. Refined forms of land management, such as the cultivation of legumes, can reduce the use of fertilizers and thus also the emission of N2O. Legumes can use symbiotic nodule bacteria (rhizobia) to bind atmospheric N2 and make it available to the plant. Non-symbiotic soil microorganisms such as cyanobacteria or other heterotrophic and autotrophic prokaryotes are also able to fix N2. Furthermore, the N2-fixing enzyme nitrogenase, which is specific for most organisms, is not specific for other N2 compounds, especially N2O. To study the N2 and N2O fixation potential of soils and legumes, experiments with isotope-enriched N-gases (100 mol% 15N2 and 15N2O) were performed. Three different soil types (forest, meadow and wetland) as well as legume plants inoculated with rhizobia bacteria (Rhizobium leucaneae) (Leucaena leucocephala) were incubated in microcosms with different mixing ratios of N2 and N2O over a period of one week. The measured 15N enrichment was then used to determine the biological uptake rates. Both in plants and in soils admixtures of up to 40% N2O had no influence on the N2 fixation rate. N2 uptake rates were 1.2 ± 0.4 ug N gdw-1 d- 1in forest and grassland soils and 3.9 ± 1.2 ug N gdw-1 d- 1 in wetland soils. In contrast, the N2 fixation rates of leguminous plants were significantly higher (130 ± 40 ug N gdw-1 d- 1), with the highest accumulation not in root nodules but in the roots. In both plants and soil, the N2O fixation of 0.2 ± 0.1 ug N gdw-1 d- 1 could only be measured from a concentration of 4 vol%. The results indicate that both soils and legumes have a high potential to bind atmospheric nitrogen in the form of both N2 but not N2O. The fate of nitrogen in soil needs to be further investigated. N2 fixation seems to play an important role in wetland soils. Legumes in particular have the potential for NH4+ input and N2O reduction, as most of the solid nitrogen has been transferred to the roots, which can contribute significantly to soil nutrient input.
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Earth Sciences, Geoinformatics; DEM fusion; multi-scale analysis; WT; BEMD; N-AMD
Online: 26 October 2018 (15:26:12 CEST)
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Digital Elevation Models (DEMs) are widely used in geographic and environmental studies. In the current work, the fusion of multi-source DEMs is investigated to improve the overall accuracy of public domain DEMs. Multi-scale decomposition is an important analytical method in data fusion. Three multi-scale decomposition methods – the wavelet transform (WT), bidimensional empirical mode decomposition (BEMD) and nonlinear adaptive multi-scale decomposition (N-AMD) - are applied to the 1-arc-second Shuttle Radar Topography Mission Global digital elevation model (SRTM-1 DEM) and the Advanced Land Observing Satellite World 3D – 30 m digital surface model (AW3D30 DSM) in China. Of these, the WT and BEMD are popular image fusion methods. A new approach for DEM fusion is developed using N-AMD (which is originally invented to remove the cycle from sunspots). Subsequently, a window-based rule is proposed for the fusion of corresponding frequency components obtained by these methods. Quantitative results show that N-AMD is more suitable for multi-scale fusion of multi-source DEMs, taking the ice cloud and land elevation satellite (ICESat) global land surface altimetry data as a reference. The vertical accuracy of the fused DEM shows significant improvements of 29.6% and 19.3% in a mountainous region and 27.4% and 15.5% in a low-relief region, compared to the SRTM-1 and AW3D30 respectively. Furthermore, a slope position-based linear regression method is developed to calibrate the fused DEM for different slope position classes, by investigating the distribution of the fused DEM error with topography. The results indicate that the accuracy of the DEM calibrated by this method is improved by 16% and 13.6%, compared to the fused DEM in the mountainous region and low-relief region respectively, proving that it is a practical and simple means of further increasing the accuracy of the fused DEM.
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Earth Sciences, Environmental Sciences; flood prediction; machine learning; forecasting
Online: 26 October 2018 (11:56:27 CEST)
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Floods are among the most destructive natural disasters, which are highly complex to model. The research on the advancement of flood prediction models has been contributing to risk reduction, policy suggestion, minimizing loss of human life and reducing the property damage associated with floods. To mimic the complex mathematical expressions of physical processes of floods, during the past two decades, machine learning (ML) methods have highly contributed in the advancement of prediction systems providing better performance and cost effective solutions. Due to the vast benefits and potential of ML, its popularity has dramatically increased among hydrologists. Researchers through introducing the novel ML methods and hybridization of the existing ones have been aiming at discovering more accurate and efficient prediction models. The main contribution is to demonstrate the state of the art of ML models in flood prediction and give an insight over the most suitable models. The literature where ML models are benchmarked through a qualitative analysis of robustness, accuracy, effectiveness, and speed have been particularly investigated to provide an extensive overview on various ML algorithms usage in the field. The performance comparison of ML models presents an in-depth understanding about the different techniques within the framework of a comprehensive evaluation and discussion. As the result, the paper introduces the most promising prediction methods for both long-term and short-term floods. Furthermore, the major trends in improving the quality of the flood prediction models are investigated. Among them, hybridization, data decomposition, algorithm ensemble, and model optimization are reported the most effective strategy in improvement of the ML methods. This survey can be used as a guideline for the hydrologists as well as climate scientists to assist them choosing the proper ML method according to the prediction task conclusions.
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Earth Sciences, Geoinformatics; hydro-meteorological factors; large-scale atmospheric circulation systems; South Asia monsoon; streamflows; source region of the Yangtze River
Online: 26 October 2018 (11:52:13 CEST)
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Studying hydro-meteorological factors variations and its links to large-scale atmospheric circulation systems can facilitate the understanding of the hydrological processes and sustainable water resources management in the source region of the Yangtze River (SRYR). Currently, researches mostly focused on the temporal and spatial variation characteristics in hydro-meteorological factors; however, researches on the hydro-meteorological variations and its links to large-scale atmospheric circulation systems in the SRYR are scarce. Based on long-term hydro-meteorological and reanalysis data, this research investigated multiscale variations of hydro-meteorological factors and its links to large-scale atmospheric circulation characteristic indices during 1957~2012 in the SRYR. The results showed that the amounts of streamflows and precipitation in the SRYR declined during the 1990s. Since the 2000s, the amounts of streamflows and precipitation had increased significantly climate in the SRYR. The change trends of precipitation and streamflows in the SRYR are synergetic at annual and seasonal scales, and have three significant periods, namely 3~5 years, 15–20 years and 30–40 years. The South Asia monsoon (SAM) plays a relatively more important role in the hydro-meteorological factors changes in the SRYR. The relative contributions of SAM to streamflows and precipitation changes were 83.6% and 78%, respectively. During the driest (wettest) year, the SAM is relatively weak (strong), and brings less (more) southwest airflow into the SRYR, less (more) precipitation and streamflows will be generated in the SRYR.
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Earth Sciences, Geoinformatics; rational polynomial coefficients (RPCs); ziyuan-3 satellite; rigorous sensor model (RSM)
Online: 26 October 2018 (09:04:07 CEST)
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Ziyuan-3 (ZY-3) satellite is the first civilian stereo mapping satellite in China and was designed to achieve the 1: 50000 scale mapping for land and ocean. Rigorous sensor model (RSM) is required to build the relationship between the three-dimensional (3D) object space and two-dimensional (2D) image space of ZY-3 satellite imagery. However, each satellite sensor has its own imaging system with different physical sensor models, which increase the difficulty of geometric integration of multi-source images with different sensor models. Therefore, it is critical to generate generic model， especially rational polynomial coefficients (RPCs) of optical imagery. Recently, relatively a few researches have been conducted on RPCs generation to ZY-3 satellite. This paper proposes an approach to evaluate the performance of RPCs generation from RSM of ZY-3 imagery. Three scenarios experiments with different terrain features (such as ocean, city and grassland) are designed and conducted to comprehensively evaluate the replacement accuracies of this approach and analyze the RPCs fitting error. All the experimental results demonstrate that the proposed method achieved the encouraging accuracy of better than 1.946E-04 pixel in both x-axis direction and y-axis direction, and it indicates that the RPCs is suitable for ZY-3 imagery and can be used as a replacement for the RSM of ZY-3 imagery.
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Earth Sciences, Geology; BSR; gas hydrate; methane; seepage; active margin; Chile Triple Junction
Online: 26 October 2018 (06:18:51 CEST)
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Large amounts of gas hydrate are present in marine sediments offshore Taitao Peninsula, near the Chile Triple Junction. Here, marine sediments on the forearc contain carbon that is converted to methane in a zone of very high heat flow and intense rock deformation above the downgoing oceanic spreading ridge separating the Nazca and Antarctic plates. This regime enables vigorous fluid migration. Here we present an analysis of the spatial distribution, concentration, estimate of gas phases (gas hydrate and free gas) and geothermal gradients in the accretionary prism and forearc sediments offshore Taitao (45.5° - 47° S). Velocity analysis of Seismic Profile RC2901-751 indicates gas hydrate concentration values <10% of the total rock volume, and extremely high geothermal gradients (<190 °Ckm-1). Gas hydrates are located in shallow sediments (90-280 meters below the seafloor). The large amount of hydrate and free gas estimated (7.21x1011 m3 and 4.1x1010 m3, respectively), the high seismicity, the mechanically unstable nature of the sediments, and the anomalous geothermal conditions, set the stage for potential massive releases of methane to the ocean mainly through hydrate dissociation and/or migration directly to the seabed through faults. We conclude that the Chile Triple Junction is an important methane seepage area and should be the focus of novel geological and ecological research.
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Earth Sciences, Environmental Sciences; UAV images; mangrove; vegetation indices; Leaf Area Index (LAI)
Online: 26 October 2018 (05:32:52 CEST)
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The urban mangrove of the Vitória Bay, Espírito Santo, Southern Brazil suffers from anthropogenic impacts, which interfere in the foliar spectral response of its species. Identifying the spectral behavior of these species and creating regression models to indirectly obtain structure data like the Leaf Area Index (LAI) are powerful environmental monitoring tools. In this study, LAI was obtained in 32 plots distributed in four stations. In situ LAI regression analysis with the SAVI resulted in significant positive relationships (r2 = 0.58). Forest variability regarding the degree of maturity and structural heterogeneity and LAI influenced the adjustment of vegetation indices (VIs). The highest regression values were obtained for the homogeneous field data, represented by R. mangle plots, which also had higher LAI values. The same field data were correlated with SAVI of a RapidEye image for comparison purposes. The results showed that, images obtained by a UAV have higher spatial resolution than the Rapideye image, and therefore had a greater influence of the background. Another point is that the statistical analysis of the field data with the IVs obtained from the RapidEye image did not present high regression coefficient (r2 = 0.7), suggesting that the use of VIs applied to the study of urban mangroves needs to be better evaluated, observing the factors that influence the leaf spectral response.
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Earth Sciences, Environmental Sciences; hyperspectral images; multispectral images; spectral diversity; Shannon entropy; tropical forest; marine coral reefs; biodiversity; correlation.
Online: 25 October 2018 (16:30:53 CEST)
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Hyperspectral images are an important tool to assess ecosystem biodiversity both on terrestrial and benthic habitats. To obtain more precise analysis of biodiversity indicators that agree with indicators obtained using field data, analysis of spectral diversity calculated from images have to be validated with field based diversity estimates. The plant species richness is one of the most important indicators of biodiversity. This indicator can be measured in hyperspectral images considering the Spectral Variation Hypothesis (SVH) which states that the spectral heterogeneity is related to spatial heterogeneity and thus to species richness. The goal of this research is to capture spectral heterogeneity from hyperspectral images for a terrestrial neo tropical forest site using Vector Quantization (VQ) method and then use the result for prediction of plant species richness. The results are compared with that of Hierarchical Agglomerative Clustering (HAC). The validation of the process index is done calculating the Pearson correlation coefficient between the Shannon entropy from actual field data and the Shannon entropy computed in the images. Terrestrial dry forest and marine coastal hyperspectral images with different resolutions have been used for spectral diversity feature validation.
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Earth Sciences, Environmental Sciences; Artificial Light at Night; Light Pollution; Night Lights; VIIRS DNB
Online: 25 October 2018 (16:19:47 CEST)
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With the growing size and use of night lights time series from the Visible Infrared Imaging Radiometer Suite Day/Night Band (DNB), it is important to understand the stability of the dataset. All satellites observe differences in pixel values during repeat observations. In the case of night lights data, these changes can be due to both environmental effects and changes in light emission. Here we examine the stability of individual locations of particular large scale light sources (e.g. airports, prisons) in the monthly composites of DNB data from April 2012 to September 2017. The radiances for individual pixels of most large light emitters are approximately normally distributed, with a standard deviation of typically 15-20% of the mean. We observe geospatial autocorrelation in the monthly variations for nearby sites, while the correlation for sites separated by large distances is small. This suggests that local factors contribute most to the variation in the pixel radiances, and furthermore that averaging radiances over large areas will reduce the total variation. A better understanding of the causes of temporal variation would improve the sensitivity of DNB to lighting changes.
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Earth Sciences, Environmental Sciences; carbon; energy; campus; sustainability; city; low carbon campus
Online: 25 October 2018 (05:15:25 CEST)
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The establishment of low carbon assessment initiatives is a crucial task especially at the city level. The determination of which source of carbon contributed more require robust data set and strategic approach. Hence, by using the campus as a small city approach, the establishment of carbon assessment and its’ reduction initiatives was required to keep track of the hotspot of the carbon source. The substantial amount of carbon source from campus operations such as energy consumption in the building, waste generation, and water consumption were identified. Moreover, as institutions of higher education, the execution of low carbon campus was initiated structurally involves the triangulation of research activities, teaching & learning and as well as campus operations or known as campus living lab approach. The application of low carbon cities framework, LCCF and assessment system enables to strategize the low carbon campus initiatives through the use of carbon footprint concept and the LCCF carbon track.
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Earth Sciences, Geoinformatics; digital terrain models; DTM vertical accuracy; DTM comparison; hydrologeomorphological Modelling; Mediterranean catchments
Online: 24 October 2018 (08:27:47 CEST)
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Digital Terrain Models (DTMs) are currently a fundamental source of information in Earth Sciences. However, DTM-based studies can contain remarkable biases if limitations and inaccuracies of these models are disregarded. In this work, four freely available datasets such as SRTM C-SAR DEM, ASTER GDEM V2 and two airborne LiDAR derived DTMs (at 5 and 1 m spatial resolution, respectively) were analysed in a comparative study in three geomorphologically contrasted catchments located in Mediterranean geoecosystems under intensive human land use influence. Vertical accuracy as well as the influence of each dataset characteristics on hydrological and geomorphological modelling applicability were assessed by using classic geometric and morphometric parameters and the more recently proposed index of sediment connectivity. Overall vertical accuracy – expressed as Root Mean Squared Error (RMSE) and Normalized Median Deviation (NMAD) – revealed the highest accuracy in the cases of the 1 m (RMSE = 1.55 m; NMAD = 0.44 m) and 5 m LiDAR DTMs (RMSE = 1.73 m; NMAD = 0.84 m). Vertical accuracy of SRTM was lower (RMSE = 6.98 m; NMAD = 5.27 m) but considerably higher than in the case of ASTER (RMSE = 16.10 m; NMAD = 11.23 m). All datasets were affected by systematic distortions. As a consequence, propagation of these errors caused negative impacts on flow routing, stream network and catchment delineation and, to a lower extent, on the distribution of slope values. These limitations should be carefully considered when applying DTMs for hydrogeomorphological modelling.
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Earth Sciences, Geophysics; Climate sensitivity; scale invariance; long-range persistence; climate variability; emergent constrains
Online: 23 October 2018 (15:59:17 CEST)
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Earth's global surface temperature shows variability on an extended range of temporal scales and satisfies an emergent scaling symmetry. Recent studies indicate that scale invariance is not only a feature of the observed temperature fluctuations, but an inherent property of the temperature response to radiative forcing, and a principle that links the fast and slow climate responses. It provides a bridge between the decadal- and centennial-scale fluctuations in the instrumental temperature record, and the millennial-scale equilibration following perturbations in the radiative balance. In particular, the emergent scale invariance makes it possible to infer equilibrium climate sensitivity (ECS) from the observed relation between radiative forcing and global temperature in the instrumental era. This is verified in ensembles of Earth system models (ESMs), where the inferred values of ECS correlate strongly to estimates from idealized model runs. For the range of forcing data explored in this paper, the method gives best estimates of ECS between 2.3 and 3.4 K.
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Earth Sciences, Environmental Sciences; road slopes; sheet erosion; chip; slash; rehabilitate; Turkey
Online: 23 October 2018 (15:01:58 CEST)
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This study compared the use of chip and slash to minimize the loss of sediment on newly constructed forest road slopes and investigated the annual amount of sediment loss on bare forest road slopes. A runoff block (sample field) was established for each of the four designated test sites (two cutslopes and two fillslopes). Each block had three runoff plots. One of the runoff plots was left empty for the control (CNT), while chip (C) and slash (S), respectively, were deposited in the other two. A total of 108 water samples were taken from the test sites and the amount of their suspended sediment calculated in the laboratory. As a result of this study, it was determined that the amount of soil loss in the control plots was about 1.26 times higher than in the slash plots and 2.21 times higher than in the chip plots. According to the results of variance analysis on the amounts of sediment, a statistically significant difference was found between the suspended sediment quantities transported on the road slopes (P <0.05). However, no statistically significant difference between the suspended sediment quantities transported in the plots and the other variables of aspect, gradient or road slope was revealed by the t-test (P >0.05).
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Earth Sciences, Environmental Sciences; Korean fir; hierarchical regression model; climate change; seedling survival; dwarf bamboo; drought
Online: 23 October 2018 (05:00:38 CEST)
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Regional declines of the Korean fir (Abies koreana) have been observed since the 1980s on the subalpine region. To explain this decline, it is fundamental to investigate the degree to which environmental factors have contributed to plant distributions on diverse spatial scales. We applied a hierarchical regression model to determine quantitatively the relationship between the abundance of Korean fir (seedlings) and diverse environmental factors across two different ecological scales. We measured Korean fir density and the occurrence of its seedlings in 102 (84) plots nested at five sites and collected a range of environmental factors at the same plots. Our model included hierarchical explanatory variables at both site-level (weather conditions) and plot-level (micro-topographic factors, soil properties, and competing species). The occurrence of Korean fir seedlings was positively associated with moss cover and rock cover but negatively related to dwarf bamboo cover. On site-level, winter precipitation was significantly positively related to the occurrence of seedlings. A hierarchical Poisson regression model revealed that Korean fir density were negatively associated with slope aspect, topographic position index, Quercus mongolica cover, and mean summer temperature. Our results suggest that drought and competition with other species are factors which halt the survival of Korean fir. We can predict that the population of Korean fir will continue to decline on the Korean Peninsula due to rising temperatures and seasonal drought, and only a few Korean fir will survive on northern slopes or valleys where competition with dwarf bamboo and Q. mongolica can be avoided.
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Earth Sciences, Environmental Sciences; craft brewery, greenhouse gas accounting, carbon regulation, carbon footprint, cap and trade, institutional theory
Online: 22 October 2018 (15:40:11 CEST)
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A growing number of companies in the brewery industry have made commitments to measure and reduce their greenhouse gas (GHG) emissions. However, many brewers, particularly craft brewers with relatively low rates of production, have struggled to meet these commitments. The purpose of this research was to investigate the challenges and benefits of measuring and reducing GHG emissions in the craft brewery industry. The research was conducted in Ontario, Canada, which has seen strong recent growth in the craft brewery industry. A case study and semi-structured interviews among Ontario Craft Brewers were conducted. The case study found that indirect (scope 3 emissions under the WBCSD & WRI GHG Protocol) GHG sources accounted for 46.4% of total GHGs, with major sources from barley agriculture, malted barley transportation, and bottle production. Direct emissions (scope 1) accounted for only 14.9% of GHGs, while scope 2 emissions, comprised mainly of energy consumption, accounted for 38.7% of GHGs. The case study and interviews found that the main challenges in calculating brewery GHGs are secondary data availability, technical knowledge, and finances. The study also found that the main benefits for Ontario breweries to measure their GHGs include sustainability marketing and preserving the environment. The interviews also found a poor understanding of carbon regulation among Ontario Craft Brewers, which is interesting considering that Ontario implemented a provincial cap and trade program in 2017.
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Earth Sciences, Other; ice; surface roughness; remote sensing; MISR
Online: 22 October 2018 (09:50:48 CEST)
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Sea ice surface roughness affects ice-atmosphere interactions, serves as an indicator of ice age, shows patterns of ice convergence and divergence, affects the spatial extent of summer melt ponds, and ice albedo. We have developed a method for mapping sea ice surface roughness using angular reflectance data from the Multi-angle Imaging SpectroRadiometer (MISR) and lidar-derived roughness measurements from the Airborne Topographic Mapper (ATM). Using an empirical data modeling approach, we derived estimates of Arctic sea ice roughness ranging from centimeters to decimeters meters within the MISR 275-m pixel size. Using independent ATM data for validation, we find that histograms of lidar and multi-angular roughness values are nearly identical for areas with roughness <20 cm but that for rougher regions, the MISR-derived roughness has a narrower range of values than the ATM data. The algorithm is able to accurately identify areas that transition between smooth and rough ice. Because of its coarser spatial scale, MISR-derived roughness data have a variance of about half that ATM roughness data.
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Earth Sciences, Environmental Sciences; ecology technology; gravel contact oxidation; surface flow constructed wetlands; water quality; river pollution index
Online: 22 October 2018 (07:50:42 CEST)
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Polluted river is a primary problem occurred in Changhua County, Taiwan because of rapid and massive developments of agriculture and industry. Water sample belongs to the water exhausted from influent of Yangzi-Cuo river, ci-tong jiao, Changhua County, and ecology technologies, which combined with gravel contact oxidation and surface flow constructed wetlands, are employed to enhance the water quality. Ecology technology is a useful and ordinary process which focuses on original treatment of pollution through chemical, physical, and biological procedures based on the mediums of soil, plant, water, and microorganism from pure environment. Moreover, this study aims on minimizing river pollution index (RPI) of Yangzi-Cuo river by using combinations of gravel contact oxidation and surface flow constructed wetlands. The inflow volume of water sample in suit is measured as 1,534-2,261 cubic meters per day (CMD). The major pollution in water sample involves of suspended solid (SS), ammoniacal nitrogen (NH3-N), total phosphorus (TP), total nitrogen (TN), and biochemical oxygen demand (BOD), and the values of above indexes is ranged as 10.0-26.7 mg/L, 0.9-14.0 mg/L, 1.2-14.1 mg/L, 11.1-18.2 mg/L, and 0.5-3.6 mg/L, respectively. Efficiencies of pollution elimination on SS, NH3-N, TP, TN, and BOD were depicted as 24.2-93.1%, 58.3-86.2%, 5.2-85.0%, 59.4-77.2%, and 46.3-76.4%, correspondingly, after purification treatment of ecology technology. As the result, ecology technology is benefit for the purification treatment of polluted river.
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Earth Sciences, Geology; Au-Ag low-sulphidation epithermal mineralization; Kremnica; gold; selenium; clausthalite; naumannite; miargyrite; pyrargyrite-proustite; polybasite-pearceite; diaphorite; Pb-Sb sulphosalts
Online: 22 October 2018 (05:35:42 CEST)
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Selenium-rich Au-Ag mineralization has been discovered in the Kremnica ore district, central Slovakia. The mineralization is hosted by a single quartz-dolomite vein hosted by Neogene propyllitized andesites of the Kremnica stratovolcano. Ore mineralogy and crystal chemistry of individual ore minerals have been studied here. The early base-metal ore mineralization composed of pyrite, sphalerite and chalcopyrite lacks selenium, whereas the superimposed Au-Ag paragenesis is Se-enriched. The Au-Ag alloys, uytenbogaardtite, minerals of the galena-clausthalite series, acanthite-naumannite series, diaphorite, miargyrite, pyrargyrite-proustite, polybasite group, minerals of the tetrahedrite group and andorite branch (andorite IV, andorite VI, Ag-excess fizélyite), freislebenite, and rare Pb-Sb sulphosalts (scaiinite, robinsonite, plagionite) have been identified here. Besides selenides, the most Se-enriched phases are miargyrite, proustite-pyrargyrite, and polybasite-pearceite, whose Se contents are among the highest reported worldwide. In addition, one new phase has been found, corresponding to a Se-analogue of pearceite containing 2.08 - 3.54 apfu Se. The style of mineralization, paragenetic situation, and chemical trends observed in individual minerals are comparable to those of Au-Ag low-sulphidation epithermal Au-Ag mineralizations of the Kremnica and neighboring Štiavnica and Hodruša-Hámre Ore Districts, however, the pronounced enrichment in selenium is a specific feature of the studied vein only.
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Earth Sciences, Other; saponite-containing waters; diamond processing plants; cryogenic treatment; electrochemical separation; saponite product applications
Online: 22 October 2018 (04:34:23 CEST)
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The analysis of methods of cleaning and processing of saponite-bearing technogenic waters of diamond mining enterprises of the Arkhangelsk region is carried out. The perspective of the electrochemical separation method for extracting saponite from man-caused waters, providing a targeted change in its structural-texture, physico-chemical and mechanical properties, is shown. The possible directions of realization of saponite and products of its modification in various branches of industry are considered.
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Earth Sciences, Environmental Sciences; Sample size, Measurement error, Generalized Additive Model, GAM, Réseau Hydrique.
Online: 19 October 2018 (16:53:50 CEST)
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Live fuel moisture content (LFMC) influences fire activity at landscape scale and fire behavior in laboratory experiments. However, field evidences linking LFMC to fire behavior are very limited despite numerous field experiments. In the present study, we reanalyze a shrubland fire dataset with a special focus on LFMC to explain this counterintuitive outcome. We found that this controversy might result from three reasons. First, the range of experimental LFMC data was too moist to reveal significant effect with the widespread exponential or power functions. Indeed, LFMC exhibited a strong effect below 100%, but marginal above this threshold, contrary to these functions. Second, we found that the LFMC significance was unlikely when the size of the dataset was smaller than 40. Finally, a complementary analysis suggested that 10 to 15% of random measurement error in variables could lead to an underestimation by 30 % of the LFMC effect. The effect of LFMC in field experiments is thus stronger than previously reported in the range prevailing during the actual French fire season and in accordance with observations at different scales. This highlights the need to improve our understanding of the relationship between LFMC and fire behavior to refine fire danger predictions.
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Earth Sciences, Environmental Sciences; Sentinel-1 backscatter; polarization; Terra MODIS; NDVI; soil moisture
Online: 19 October 2018 (13:28:18 CEST)
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Soil moisture (SM) plays an essential role in environmental studies related to wetlands, an ecosystem sensitive to climate change. Hence, there is the need for its constant monitoring. SAR (Synthetic Aperture Radar) satellite imagery is the only mean to fulfill this objective regardless of the weather. The objective of the study was to develop the methodology for SM retrieval under wetland vegetation using Sentinel-1 (S-1) satellite data. The study was carried out during the years 2015–2017 in the Biebrza Wetlands, situated in northeastern Poland. At the Biebrza Wetlands, two Sentinel-1 validation sites were established, covering grassland and marshland biomes, where a network of 18 stations for soil moisture measurement was deployed. The sites were funded by the European Space Agency (ESA), and the collected measurements are available through the International Soil Moisture Network (ISMN). The NDVI (Normalized Difference Vegetation Index) was derived from the optical imagery of a MODIS (Moderate Resolution Imaging Spectroradiometer) sensor onboard the Terra satellite. The SAR data of the Sentinel-1 satellite with VH (vertical transmit and horizontal receive) and VV (vertical transmit and vertical receive) polarization were applied to soil moisture retrieval for a broad range of NDVI values and soil moisture conditions. The new methodology is based on research into the effect of vegetation on backscatter () changes under different soil moisture and vegetation (NDVI) conditions. It was found that the state of the vegetation may be described by the difference between VH and VV, or the ratio of VV/VH, as calculated from the Sentinel-1 images. The most significant correlation coefficient for soil moisture was found for data that was acquired from the ascending tracks of the Sentinel-1 satellite, characterized by the lowest incidence angle, and SM at a depth of 5 cm. The study demonstrated that the use of the inversion approach, which was applied to the new developed models and includes the derived indices based on S-1, allowed the estimation of SM for peatlands with reasonable accuracy (RMSE ~ 10 vol. %). Due to the temporal frequency of the two S-1 satellites’ (S-1A and S-1B) acquisitions, it is possible to monitor SM changes every six days. The conclusion drawn from the study emphasizes a demand for the derivation of specific soil moisture retrieval algorithms that are suited for wetland ecosystems, where soil moisture is several times higher than in agricultural areas.
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Earth Sciences, Environmental Sciences; Anion exchange, DOC, Dissolved phosphorus, Forest soil, Lysimeters, P transport
Online: 18 October 2018 (10:10:20 CEST)
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Incidental P losses from non-point sources may contribute to eutrophication and to decreased soil fertility. These incidents have been related to heavy rainfall on freshly fertilized agricultural soils and little is known about such incidents on more natural soils or in forests. The aim of this work is to determine if incidents of high P leaching also occur in spruce forests, and if such incidents are of significance in P cycling. We found a peak in the mineral soil solution showing that single events of high P leaching occur. The orthophosphate concentration in the Bf-horizon of the 80-year old spruce forest peaked in the autumn of the second year of a continuous monitoring. The concentration increased by more than 85 times compared to the highest concentration obtained earlier during the sampling. The amount leached during this 6 months peak is 10 times higher than the average annual leaching. This P leaching might be due to a combination of high P deposition/through-fall and a high anion exchange with dissolved-organic-carbon and Cl-. We suggest that single events of high sub-surface P leaching may contribute to the overall P leaching, and might increase with the global warming as more DOC is expected to be released to the soil solution.
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Earth Sciences, Geoinformatics; floating algae index (FAI); normalized difference vegetation index (NDVI); remote sensing; seaweed enhancing index (SEI); seaweed
Online: 18 October 2018 (05:10:09 CEST)
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Seaweeds are regarded as one of the valuable coastal resources because of their usage in human food, cosmetics, and other industrial items. They also play a significant role in providing nourishment, shelter, and breeding grounds for fish and many other sea species. This study introduces a newly developed seaweed enhancing index (SEI) using spectral bands of near-infrared (NIR) and shortwave infrared (SWIR) of Landsat 8 satellite data. The seaweed patches in the coastal waters of Karachi, Pakistan were mapped using SEI, and its performance was compared with other commonly used indices - Normalized Difference Vegetation Index (NDVI) and Floating Algae Index (FAI). The accuracy of the mapping results obtained from SEI, NDVI, and FAI was checked with field verified seaweed locations. The purpose of the field surveys was to validate the results of this study and to evaluate the performance of SEI with NDVI and FAI. The performance of SEI was found better than NDVI and FAI in enhancing submerged patches of the seaweed pixels what other indices failed to do.
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Earth Sciences, Geophysics; higher-mode surface waves; dispersion curves; morphological component analysis; Radon transform
Online: 17 October 2018 (09:00:53 CEST)
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Extraction of high-resolution surface waves is essential in surface-wave survey. Because reflections usually interfere with surface waves on X component in a multicomponent seismic exploration, it is difficult to extract dispersion curves of surface waves. The situation goes more serious when the frequencies and velocities of higher-mode surface waves are close to those of PS-waves. A method for surface-wave extraction is proposed based on the morphological differences between reflections and surface waves. Frequency-domain high-resolution linear Radon transform (LRT) and time-domain high-resolution hyperbolic Radon transform (HRT) are used to represent surface waves and reflections respectively. Then, the sparse representation problem based on the morphological component analysis (MCA) is built and optimally solved to obtain high-fidelity surface waves. An advantage of our method is its ability to extract surface waves when their frequencies and velocities are close to those of reflections. Furthermore, results of synthetic and field examples confirm that the proposed method can attenuate the distortion of surface-wave dispersive energy caused by reflections, which contributes to extracting accurate dispersion curves.
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Earth Sciences, Other; Ergonomic Workplace Analysis; ergonomics solutions; collaborative environment; drilling centers
Online: 17 October 2018 (08:28:01 CEST)
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Drilling centers are collaborative environments dedicated to facilitate decision-making in the well construction, where multidisciplinary teams work to support operations. The oil operators usually have drilling centers with different types of ergonomic features with considerable potential of integration, creating the opportunity to an Ergonomic Workplace Analysis. This paper aims to present the analysis of infrastructure requirements of one specific company in Brazil. The method was based on a survey with employees, which, coped with a statistical analysis, enabled understanding the impact of the layout requirements. The result is an approach to design collaborative environments, standardizing and defining models for the industry.