중규모 대류계에 의한 호남지방 강수 특성

Abstract

The Honam region frequently experiences meteorological disasters due to the abrupt development of mesoscale convective systems caused by various topographic effects. Therefore, in this study, the precipitation characteristics due to mesoscale convective systems were analyzed through the statistical analysis and case analysis of the precipitation cases due to the mesoscale convective systems that had occurred in the Honam region from June to October every year for the last 10 years (2002-2011). As for the data used in this study, for the synoptic analysis, the surface weather chart and 500 hPa weather chart, which had been produced by the Korea Meteorological Administration, were used; for the analysis of the mesoscale convective systems depending on the scale and the analysis of the precipitation characteristics, the satellite data, radar data, and AWS observation data were used; and for the case analysis, the data obtained from KLAPS was used to analyze the non-synoptic characteristics of the mesoscale convective systems. During the research period, there were a total of 196 precipitation cases due to the mesoscale convective systems, and they were classified into the meso-α, β, and γ scales using the satellite image, radar image, and AWS precipitation distribution chart in order to analyze the occurrence scale of the mesoscale convective systems depending on the case. The analysis results indicated that 69% of the precipitation cases due to the mesoscale convective systems, which occurred in the Honam region, occurred due to the effect of the mT air mass. Among them, 35% was during mT contraction, and 34% was during mT expansion, which showed that the difference between the contraction and the expansion was very small. The number of yearly occurrences showed large variation, and thus a significant trend could not be found. However, considering that it continuously occurred more than 20 times for the last 4 years, it is thought that the number of occurrences has an increasing trend. As for the number of monthly occurrences, 40% was focused on August. This is thought to be because August is the most strongly affected by mT, and convection is active due to strong solar radiation. The precipitation mostly occurred between 1300 and 2000 LST, and it peaked at 1600 LST and 1700 LST. The durations of the precipitation were 3.24 hours for the meso-α scale, 1.99 hours for the meso-β scale, and 1.05 hours for the meso-γ scale. The difference in the duration was about 1 hour depending on the scale. The precipitation distribution chart was drawn based on the precipitation data of AWS spot 137 in the Honam region, using SUFER11. The schematic diagram was drawn by expressing the precipitation concentration zone and the zonal wind system depending on the topographic characteristics of each case, for the meso-β scale that occurred most frequently. For the case analysis, the case of the heavy rainfall in the Gwangju region on August 8, 2008 was selected, and the real-time analysis, remote sensing image analysis, and numerical model data analysis were performed. This case was the β-scale case in which strong precipitation occurred in a short time focusing on part of the Honam region centered on Gwangju. Synoptic forecasting was difficult because the synoptic environment was weak. For the prognostic chart of the numerical model data, precipitation forecasting was possible to a certain degree, but the position and amount of the precipitation could not be accurately simulated. To increase the forecasting possibility of this case, it is thought that when there is a possibility of local heavy rainfall due to general instability, the heavy rainfall cell monitoring using meteorological satellite images and meteorological radar, the hourly atmospheric pressure changing trend examination based on the weather chart of the Korean Peninsula, and the low-level lability increasing trend consideration based on an adiabatic diagram are required.