서해 SST 변화가 호남지방 대설에 미치는 영향에 관한 수치연구

Abstract

ABSTRACT

Numerical Study on the Impact of Sea Surface Temperature of Yellow Sea on the Heavy Snowfall over Honam Districts

Mo, Sun-Jin. Advisor : Prof. Ryu, Chan-Su Ph.D. Department of Atmospheric Science, Graduate School of Chosun University

Analysis and numerical experiments of the development mechanism of a heavy snowfall happening in the Yellow Sea of the Korean Peninsula were carried out. Especially this study mainly focused on the impacts of mesoscale meteorological phenomena on a heavy snowfall and was intended to provide basic data in trying to reduce the concerned natural disasters. Employed data to conduct the analysis were the synoptic charts provided by the Korean Meteorological Administration and the numerical data produced on the Numerical Weather Prediction Model(including synoptic meteorological observations, radiosonde data, satellite data, RDAPS, and two-dimensional sea surface temperature in the Yellow Sea). Recordable heavy snowfall over Honam districts happened on December 21, 2005. Analyzed to understand the developmental structure of a heavy snowfall were the horizontal synoptic charts(500 hPa synoptic charts in the Northern Hemisphere, 850 hPa 24-hour temperature changes, and surface weather maps by the hours) and the patterns of ascents(500 hPa vorticity, jet streams of 300 hPa and 850 hPa, Gunsan wind profiler, and 21-day 00UTC 850hPa omega values). Several numerical experiments were also conducted using MM5 to examine the development of heavy snowfall cells according to the two-dimensional distribution of sea surface temperature. The changes of the intensity of snowfall convection cells were strongly associated with the two-dimensional distribution of sea surface temperature in the Yellow Sea. As a result, the two-dimensional distribution of sea surface temperature in the Yellow Sea didn't work the formation of heavy snowfall cells directly. convection cells were developed in the Yellow Sea when the sea surface temperature was low. Although SST distribution was not predominate to make convection cell, it is strongly associated with the variation of snowfall intensity. In the case investigated in the study, the heavy snowfall cells developed in the sea near the Honam region, which means that the snowfall considerably dropped in the inland areas. Thus it's critical to figure out two-dimensional water temperature in the Yellow Sea in estimating the amount of a heavy snowfall and predicting one in the Honam region. Since the water temperature gradient plays a crucial role in the coastal areas in the Honam region, the distribution of the water temperature gradient and precipitable water will make some of the major indexes to estimate the amount of a snowfall in the inland areas of the Honam region.