Ocean Responses to Typhoon Soulik (1819) around Korea

We investigated the ocean responses to typhoon Soulik (1819) when it was approaching and landing on the Korean peninsula in August, 2018. During the typhoon passage period, very severe sea surface conditions were recorded such as 15 m of maximum wave height and 35 m/s in gusts, and a 10 degrees C water temperature decrease at the buoy station near Jeju Island. The operational storm surge prediction system of the Korea Meteorological Administration estimated over 50 cm of positive surge near the typhoon center in the approaching stage, and after the typhoon passed, a negative (reverse) storm surge lower than 30 cm was shown off the southern sea of Jeju Island, revealing a cyclonic circulation pattern of the surface water from the satellite altimeter data. According to one-day cycling Argo float observations near the landfall area in the Yellow Sea, temperature and salinity profiles during the typhoon activity showed a sudden deepening of the thermocline and halocline, and then up and down fluctuations between 30-50 m in depth. The temperature decreased by about 2 degrees C in the surface layer and the thermocline layer was deepened by about 10 m from 30 to 40 m in depth while the typhoon was exerting its influence. Salinity in the surface layer showed a sudden change before and after the typhoon, revealing an increase and decrease in 0-15 m and a decrease and increase below 20 m in depth, and the halocline manifested a similar pattern of variation as the thermocline.