Future changes in the extreme sea surface wind over the Korean Waters projected by CORDEX regional climate models

Abstract

Extreme sea surface wind plays a crucial role in coastal safety including flooding and coastalerosion mainly by changing sea level and ocean wind waves, and the characteristics of the extremesea surface wind can be influenced by globalwarming. In this study, we analysed changes inextreme sea surface wind over the Korean Waters projected by five regional climate models (RCMs)participating CORDEX-EA (Coordinated Regional climate Downscaling Experiment-East Asia)downscaling project, by using daily mean winds for past (historical experiment for 1980-2004) andfuture climate (two different climate scenarios (rcp4.5 and rcp8.5) for 2025-2049). In rcp8.5 scenario,the RegCM4 and the YSU-RSM models show that extreme wind speed is projected to be decreasedin winter while it will be increased in summer(especially in the East Sea). However, the other threemodels show a negligible change in extreme wind speed. On the other hand, direction of extremewind, a critical factor in coastal erosion over the Korean Waters, is generally projected to bechanged: more frequent easterly wind and less frequent westerly wind in the future. Our resultssuggest that, although there are some consistent future changes in extreme sea surface wind overthe Korean waters, the projected changes by the RCMs are considerably different depending onseasons and models.arming. In this study, we analysed changes inextreme sea surface wind over the Korean Waters projected by five regional climate models (RCMs)participating CORDEX-EA (Coordinated Regional climate Downscaling Experiment-East Asia)downscaling project, by using daily mean winds for past (historical experiment for 1980-2004) andfuture climate (two different climate scenarios (rcp4.5 and rcp8.5) for 2025-2049). In rcp8.5 scenario,the RegCM4 and the YSU-RSM models show that extreme wind speed is projected to be decreasedin winter while it will be increased in summer(especially in the East Sea). However, the other threemodels show a negligible change in extreme wind speed. On the other hand, direction of extremewind, a critical factor in coastal erosion over the Korean Waters, is generally projected to bechanged: more frequent easterly wind and less frequent westerly wind in the future. Our resultssuggest that, although there are some consistent future changes in extreme sea surface wind overthe Korean waters, the projected changes by the RCMs are considerably different depending onseasons and models.