Future changes in the mean and extreme sea surface winds over the East Asian marginal seas projected by regional climate models

Abstract

Sea surface wind, especially extreme winds, plays a crucial role in coastal safety including flooding and coastal erosion mainly by changing sea level and ocean wind waves, and the regional characteristics of sea surface wind can be in uenced by global warming. In this study, we investigate future changes in sea surface wind (both in mean and extreme winds) due to global warming in the East Asian marginal seas (EAMS) projected by four different regional climate models contributing to CORDEX-EA (COordinated Regional climate Downscaling Experiment-East Asia) downscaling project, by using daily mean winds for the present (historical runs for 1980-2004) and the future climate (RCP4.5 scenario run for 2025-2049). In general, the climatological-mean wind speed is projected to decrease up to 30 % in winter, but to increase up to 40 % in summer, indicating seasonally different large-scale atmospheric responses to global warming in EAMS. The prevailing wind direction, a critical factor in coastal erosion in EAMS, is projected to be signi cantly changed in both winter and summer, contributing to the changes in the mean wind speed. Extreme winds, de ned as an annual maximum of the wind speed, show negligible changes with considerably large intermodel di erences. Our ndings suggest that projected future changes in sea surface wind over EAMS can be considerably di erent depending on seasons and models.