Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Nat. Hazards Earth Syst. Sci., 16, 927-939, 2016
https://doi.org/10.5194/nhess-16-927-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
12 Apr 2016
Characteristics of mesoscale-convective-system-produced extreme rainfall over southeastern South Korea: 7 July 2009
Jong-Hoon Jeong1, Dong-In Lee2, Chung-Chieh Wang3, and In-Seong Han4 1Radar Analysis Division, Weather Radar Center, KMA, Seoul, Republic of Korea
2Department of Environmental Atmospheric Sciences, Pukyong National University, Busan, Republic of Korea
3Department of Earth Sciences, National Taiwan Normal University, Taipei, Taiwan
4Oceanic Climate and Ecology Research Division, National Institute of Fisheries Science, Busan, Republic of Korea
Abstract. An extreme-rainfall-producing mesoscale convective system (MCS) associated with the Changma front in southeastern South Korea was investigated using observational data. This event recorded historic rainfall and led to devastating flash floods and landslides in the Busan metropolitan area on 7 July 2009. The aim of the present study is to analyse the influences for the synoptic and mesoscale environment, and the reasons that the quasi-stationary MCS causes extreme rainfall. Synoptic and mesoscale analyses indicate that the MCS and heavy rainfall occurred in association with a stationary front which resembled a warm front in structure. A strong southwesterly low-level jet (LLJ) transported warm and humid air and supplied the moisture toward the front, and the air rose upwards above the frontal surface. As the moist air was conditionally unstable, repeated upstream initiation of deep convection by back-building occurred at the coastline, while old cells moved downstream parallel to the convective line with training effect. Because the motion of convective cells nearly opposed the backward propagation, the system as a whole moved slowly. The back-building behaviour was linked to the convectively generated cold pool and its outflow boundary, which played a role in the propagation and maintenance of the rainfall system. As a result, the quasi-stationary MCS caused a prolonged duration of heavy rainfall, leading to extreme rainfall over the Busan metropolitan area.

Citation: Jeong, J.-H., Lee, D.-I., Wang, C.-C., and Han, I.-S.: Characteristics of mesoscale-convective-system-produced extreme rainfall over southeastern South Korea: 7 July 2009, Nat. Hazards Earth Syst. Sci., 16, 927-939, https://doi.org/10.5194/nhess-16-927-2016, 2016.
Publications Copernicus
Download
Short summary
An extreme rainfall-producing mesoscale convective system (MCS) associated with the Changma front in south-eastern South Korea was investigated using observational data. The aim of the present study is to analyze and better understand the synoptic and mesoscale environment and the behaviour of the MCS causing natural hazards over South Korea.
An extreme rainfall-producing mesoscale convective system (MCS) associated with the Changma...
Share