The Influence of Sea Surface Temperature From ECMWF Reanalysis Data on the Nonuniformity of Evaporation Duct.

Based on air temperature, relative humidity, air pressure, and wind speed data from 4 buoy stations in the northern South China Sea, the homogeneity of the evaporation duct height (EDH) obtained from sea surface temperature (SST) from buoys and SST from the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 Reanalysis (ERA-5) data are compared using the Naval-Postgraduate-School (NPS) model. The findings are given as follows: (1) the SST of the ERA-5 has highly accurate (the difference between the buoys and ERA-5 is mainly falling in –0.5°C~1.5°C) and shows strong correlations (≥0.95) with the observed data. (2) The probability of the EDH difference at –2m~2m obtained from the ERA-5 is lower than the actual observation, which underestimates the uniformity of the EDH. (3) The SST difference of buoys and ERA-5 at 0°C to 1.0°C has a more significant impact on the assessment of non-uniformity of EDH than the SST difference at –0.5°C~0°C and 1.0°C~1.5°C (take up above 60%). In conclusion, although the uniformity of the EDH may be underestimated based on the ERA-5 data, it still demonstrates the uniformity characteristic of the EDH quite well.