ARTICLE | doi:10.20944/preprints202207.0248.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Landsat; urban growth; Land Use Land Cover (LULC); remote sensing; urbanisation; NDVI
Online: 18 July 2022 (04:49:07 CEST)
Land Use Land Cover (LULC) change and urban growth have a significant influence on local climate of cities. From 1985 to 2021 the population of Baghdad increased by 103%. Therefore, the risen question is how this expansion influences the temperature of the city. The study aims to identify urban growth of Baghdad, investigate its influence on variation of Land Surface Temperature (LST) and identify the main factors that control the surface temperature of the city. Three Landsat images from 1985 to 2021, in addition to sixteen potential factors, were used in the study. Our findings suggest that during the study period, vegetated areas declined by 39% while built-up class increased by 139%. Bare soil recorded the highest surface temperature. The study found that surface temperature has a strong inverse relationship with vegetation (Normalized Difference Vegetation Index (NDVI): r = -0.62, p < 0.001) and moisture (Normalized Difference Moisture Index (NDMI): r = -0.65, p < 0.001). Therefore, increasing vegetation and water body lead to decrease temperature of the city. Our findings help policymakers to deal with climatic issues rising from urban growth of the city.
ARTICLE | doi:10.20944/preprints202001.0023.v1
Subject: Earth Sciences, Geophysics Keywords: Land Use Land Cover (LULC); Land Surface Temperature (LST); Google Earth Engine (GEE); relationship; remote sensing indices; MODIS; global
Online: 3 January 2020 (05:03:05 CET)
Land Surface Temperature (LST) and Land Use Land Cover (LULC) are the principal aspects of climate and environment studies. The object of the study is to assess spatial relationship between LST and remote sensing LULC indices at the global and continental scale. Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua daytime LST and eight LULC MODIS indices of 2018 prepared and processed using Earth Engine Code Editor. R squared and significance of the relationship values of randomly selected points computed in R program. The research observed the relationship between examined indices and LST is significant at the 0.001 level. Normalized Difference Water Index (NDWI) and Normalized Difference Snow Index (DSI) are the dominant drivers of LST in the world, Asia and North America. In Australia and Africa, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) are the dominant drivers of LST. Albedo and Normalized Difference Soil Index (NDSI) have superior in Central America. In South America and Europe, the dominant driver of LST is NDWI. Relationship between albedo and LST is moderate inverse on a global scale. Observed relationship between LST and examined vegetation indices is positive in Europe and North America while inverse in Australia and Africa. All observed relationship between Normalized Difference Built-up Index (NDBI) and LST are positive. Association observed between NDSI and LST is positive in Australia, Africa and Central America.
ARTICLE | doi:10.20944/preprints201901.0083.v1
Subject: Earth Sciences, Geoinformatics Keywords: earthquake; anomaly detection; Google Earth Engine; outliers; interquartile range (IQR); multiparameter; brightness temperature (BT); latent heat flux (LE); land surface temperature; wind speed
Online: 9 January 2019 (11:59:14 CET)
One of the most destructive natural disasters is the earthquake which brings enormous risks to humankind. The objective of the current study was to determine the Earthquake’s remote sensing multiparameter (i.e. land surface temperature (LST), air temperature, specific humidity, precipitation and wind speed) spatiotemporal anomaly of many earthquake samples occurred during 2018 around the world. In this research 11 earthquake (M > 6:0) studied (4 samples selected in a land with transparent sky situations, 3 samples in land within cloudy situations and 4 samples in marine earthquakes). The interquartile range (IQR) and mean ± 2σ methods utilized to improve the efficiency of anomalous differences. As a result, based on the IQR method, negative anomaly before the event detected during the daytime in Mexico and during the nighttime in Afghanistan. In addition, a negative outlier of brightness temperature (BT) detected in Alaska before, after and during the event. In contrast, based on IQR and mean ± 2σ positive anomaly detected in precipitation before and after the event in all investigated examples. According to mean ± 2σ, negative anomaly LST, specific humidity, sea surface temperature (SST_100) and wind detected in most examined earthquake samples. In contrast, positive SST_0 anomaly observed in Fiji and Honduras after the earthquake. Our results suggested in marine earthquakes, for earthquake forecasting we can merge a prior negative anomaly in the wind speed and SST_100. Regarding the in land cloudy sky earthquakes, merging anomaly parameters could be the negative prior anomaly in BT, skin temperature, in contrast, a positive anomaly in precipitation. In land transparent sky earthquake, usually negative prior anomalies in air temperature, specific humidity and LST.
ARTICLE | doi:10.20944/preprints201811.0515.v1
Subject: Keywords: crashed aircraft; NDVI; albedo; MH370; remote sensing; Landsat 8; disaster; Boeing 777; panchromatic band; thermal band
Online: 21 November 2018 (05:09:14 CET)
Remote sensing data and techniques utilized for various purposes including natural disasters such as earthquake as well as flood. The research aims to consume liberates Landsat 8 images for investigating crashed airplanes such as MH370. Overall approximately 300 Landsat images with less than 10% clouds utilized in addition processed through Google Engine Platform. Due to the materials as well as the color of airplane body different from the area which is a plane crashed there, moreover, it should be the characteristics of the plane shapefile different in terms of albedo, temperature as well as vegetation index value. The research observed Landsat 8 data as well as methods utilized in this research, especially, NDVI, albedo in addition to band 4, capable to distinguish between the plane and its surrounding green area. Therefore, our result confirms during the research period, there was no plane on the location as well as MH370 not crashed in this site.
ARTICLE | doi:10.20944/preprints202209.0416.v1
Subject: Earth Sciences, Geoinformatics Keywords: GEE; Landsat 8 OLI; Multi-linear regression; Remote Sensing; Vegetation indices; Wheat and barley
Online: 27 September 2022 (09:35:20 CEST)
Wheat and barley are among the primary food resources of the world population; therefore, their growth and observation are essential in farms to enhance food security worldwide. On top of that, careful observation of the product is essential to find solutions for the issues faced during their production and to reduce the impacts of weather changes. With the advancement of Remote Sensing technology, the observation and estimation process has increased. In this study, numbers of spectral vegetation indices was used along with canopy biophysical properties ( LAI ) and biochemical properties (chlorophyll), there calculated from (Landsat 8 and Sentinel-2) satellite data. The wheat and barley samples were collected before were be ready for harvest, and a relation with the vegetarian indices was established using the Multi-Linear Regression module, in which the equations used in predicting the harvest were developed and used to create a graph for expected harvest. The result indicated that there is a strong relationship between the vegetation indices of Sentinel-2 and Landsat images and the actual grain yield with R2 of 0.77 and 0.71, respectively. The results show that the strongest correlation is observed between the LAI data obtained from Sentinel data and cereal yield data, with an R2 0.68, and the highest correlation for the indices of Landsat images is observed in the NDWI with R2 0.59 and the lowest degree of error was in the root mean square error (RMSE) for the Sentinel-2 and Landsat 8 with 0.57 and 1.54. In addition, this study also showed that the least relationship for grain yield prediction was observed between the NDRI for Sentinel-2 (R2 0.1) and SAVI for Landsat image (R2 0.47).
ARTICLE | doi:10.20944/preprints202209.0169.v1
Subject: Earth Sciences, Geoinformatics Keywords: Synthetic Aperture Rader (SAR); Optical image (Sentinel 2); Random Forest (RF); CART; GEE
Online: 13 September 2022 (10:06:14 CEST)
Observing cultivated crops and other forms of land use is an important environmental and economic concern for agricultural land management and crop classification. Crop categorization offers significant crop management data, ensuring food security, and developing agricultural policies. Remote sensing data, especially publicly available Sentinel 1 and 2 data, has effectively been used in crop mapping and classification in cloudy places because of their high spatial and temporal resolution. This study aimed to improve crop type classification by combining Sentinel-1 (Synthetic Aperture Rader (SAR)) data and the Sentinel-2 Multispectral Instrument (MSI) data. In the study, Random Forest (RF) and Classification and Regression Trees (CART) classier were used to classify grain crops (Barley and Wheat). The classification results based on the combination of Sentinel-2 and Sentinel-1 data indicated an overall accuracy (OA) of 93 % and a kappa coefficient (K) of 0.896 for RF and (89.15%, 0.84) for the CART classifier. It is suggested to employ a mix of radar and optical data to attain the highest level of classification accuracy since doing so improves the likelihood that the details will be observed in comparison to the single-sensor classification technique and yields more accurate results.
REVIEW | doi:10.20944/preprints202208.0539.v1
Subject: Earth Sciences, Environmental Sciences Keywords: drought monitoring; drought predictions; drought indices; drought models
Online: 31 August 2022 (08:47:06 CEST)
Drought is considered one of the severest natural disasters and it is difficult to predict it. This review article aimed to display the state of the art of methods used to predict and monitor types of droughts. We examine more than 30 indices and models to identify the strengths and weaknesses of methods and identify gaps remaining in this field. Examples of examined indies are Palmer Drought Severity Index (PDSI), Standardized Precipitation Index (SPI), and Standardized Precipitation Evapotranspiration Index (SPEI). The research found improvement in drought modeling, however, more focus and improvement are required to monitor and predict drought types. It also found that some methods outperform others such as PDSI, SPI, SPEI, EVI, NDVI, NDWI, VCI and TCI.