Thermodynamic Characteristics Associated with Localized Torrential Rainfall Events in the Middle West Region of Korean Peninsula
한반도 중서부 국지성 집중호우와 관련된 열역학적 특성

Sueng-Pil Jung, Tae-Yong Kwon, Sang-Ok Han
2014 Atmosphere  
Thermodynamic conditions related with localized torrential rainfall in the middle west region of Korean peninsula are examined using radar rain rate and radiosonde observational data. Localized torrential rainfall events in this study are defined by three criteria base on 1) any one of Automated Synoptic Observing System (ASOS) hourly rainfall exceeds 30 mmhr −1 around Osan, 2) the rain (> 1 mmhr −1 ) area estimated from radar reflectivity is less than 20,000 km 2 , and 3) the rain (> 10 mmhr
more » ... ) cell is detected clearly and duration is short than 24 hr. As a result, 13 cases were selected during the summer season of 10 years . It was found that the duration, the maximum rain area, and the maximum volumetric rain rate of convective cells (> 30 mmhr −1 ) are less than 9hr, smaller than 1,000 km 2 , and 15,0006 0,000 m 3 s −1 in these cases. And a majority of cases shows the following thermodynamic characteristics: 1) Convective Available Potential Energy (CAPE) > 800 Jkg −1 , 2) Convective Inhibition (CIN) < 40 Jkg −1 , 3) Total Precipitable Water (TPW) ≈ 55 mm, and 4) Storm Relative Helicity (SRH) < 120 m 2 s −2 . These cases mostly occurred in the afternoon. These thermodynamic conditions indicated that these cases were caused by strong atmospheric instability, lifting to overcome CIN, and sufficient moisture. The localized torrential rainfall occurred with deep moisture convection result from the instability caused by convective heating.
doi:10.14191/atmos.2014.24.4.457 fatcat:e3pp4lugmvaodejykiaol32ep4