Sea surface temperature (SST) diurnal warming caused by insolation is investigated using wide‐ranging hourly insolation and SST derived from the Geostationary Meteorological Satellite/Visible and Infrared Spin Scan Radiometer (GMS/VISSR). Using SST diurnal variations (ΔSSTgms) derived from the hourly VISSR SSTs and insolation, and the wind velocity derived from the Advanced Earth Observing Satellite/NASA Scatterometer (ADEOS/NSCAT), it is verified that the SST warming occurs under conditions of high insolation and weak wind. To investigate the ΔSSTgms, two simple models are applied. One SST diurnal warming estimation model (Model A) is developed with reference to Price et al. [1986, 1987] introducing the latitudinal heat loss estimated from climatic values. Another model (Model B) was proposed by Webster et al. [1996]. Because SST diurnal warming is dependent on meteorological conditions, the areas of SST warming change from day to day. However, areas of weak wind and high insolation can be specified by large‐scale atmospheric systems. Both distributions of the monthly averaged ΔSSTmodel‐A (SST diurnal warming estimated by Model A) and ΔSSTgms agree well with each other. Large SST diurnal warming has occurred at middle latitudes in the summer hemisphere and tropical regions near the land. Through this study, it is demonstrated that the combination of satellite observation and numerical models enables us to investigate the diurnal SST warming over the wide‐ranging ocean.
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