Analysis of Spatio-Temporal intensity of Sea Fog in Yellow Sea Using Visibility Data of Ocean Research Stations (ORS) and Baengnyeongdo

Abstract

While existing research on sea fog primarily relied on collecting data from ground observations in coastal areas, this study utilized municipal data from three Korea Ocean Research Stations (KORS) located in the Yellow Sea and Baengnyeongdo. The main objective was to analyze the strength of sea fog in specific locations within the Yellow Sea. The study employed the corrective distance as a measure of intensity and examined variations in sea fog strength according to the monthly and by time period of the study area. The research periods for each research station were as follows: Socheongcho Ocean Research Stations (SORS) from 2014 to 2022, Gageocho Ocean Research Stations (GORS) from 2014 to 2020, Ieodo Ocean Research Stations (IORS) from 2010 to 2015, and Baengnyeongdo from 2016 to 2022. In terms of season, the highest sea fog frequency in SORS and GORS were at 59% and 75% in spring, respectively. While in IORS, sea fog intensively occurred throughout the spring (46%) and summer (47%) seasons. On the other hand, in Baengnyeongdo, the sea fog frequency in summer, spring, autumn and winter were 41%, 25%, 17% and 17%, respectively. Between September and February the occurrence frequency was 19%, 8.1% and 7.3% in SORS, GORS and IORS, respectively which tends to decrease as it descends South of the Yellow Sea. In SORS, sea fog frequency with 0.2 km (strength 2) visibility was 49% while in the case of GORS and IORS it was 15% and 22%, respectively. Besides, the frequency of sea fog which visibility was between 0.2 and 0.5 km (strength 1) was 59% and 56% in GORS and IORS, respectively. In terms of frequency by time period, SORS and GORS showed a normalization maximum of 01 at 01:00 KST where IORS showed 02. Sea fog was not seen at 12:00 in SORS, at 13-17:00 in GORS and at 19-20:00 in IORS. In the future, we will analyze the spatial distribution of sea fog occurring in the Yellow Sea after sea fog verification using satellite images.