Surface Meteorology and Air-Sea Fluxes at the WHOTS Ocean Reference Station: Variability at Periods Up to and Including One Year

A composite, eighteen-year long record on in-situ surface meteorology and computed bulk air-sea fluxes of heat, freshwater, and momentum from an ocean site windward of Oahu are presented. Data were logged every minute over eighteen years. Methods and data quality are discussed. Statistics of one-minute, one-hour, and one-day times series are presented, and daily averaged time series provide an overview of this trade wind site. Mean wind was 6.8 m s−1 toward the west southwest, mean ocean heat gain was 23.2 W m−2 with freshwater loss of 1.2 m yr−1. Energetic sub-diurnal variability was found, with spectral peaks in solar insolation and sea level pressure, and transient, short-lived signals including insolation above the clear sky value, short periods of warm air, and downdrafts of dry air. Mean daily cycles are presented. Longer lasting events, including periods of ocean cooling, ocean heating, and hurricanes, are explored. Mean annual cycles are presented. The ocean loses heat from January through early May; then gains heat until late October and returns to loosing heat. Normalized by duration, the events examined have potential for significant contributions to the heat, freshwater, and mechanical energy exchanges.