School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea.
Department of Earth Sciences, Chosun University, Gwangju, South Korea.
PLoS One. 2019 Jan 7;14(1):e0209885. doi: 10.1371/journal.pone.0209885. eCollection 2019.
The wind- and rainfall areas of tropical cyclones (TCs) making landfall over South Korea were examined for the period 1998-2013 by using the Modern Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) and Tropical Rainfall Measuring Mission (TRMM) 3B42 data. Here, the wind- and rainfall areas were defined as the regions where wind speeds and precipitation rates exceed 14 m s-1 and 80 mm day-1 within 1000 km from the TC center, respectively. In general, TCs show significantly asymmetric wind and rainfall structures, with strong vertical wind shear appearing over South Korea during the landfall period. The rainfall area significantly increases with environmental vertical wind shear while the wind area is not sensitive to it. Composite analyses of the cases of strong and weak vertical wind shear confirm that the increase of rainfall area is related to the asymmetric convection (rising/sinking motion in the downshear-left/upshear-right side) induced by the vertical wind shear. This work highlights the importance of local atmospheric environment in determining the area primarily affected by strong winds or heavy rainfall during TC landfalls.
利用现代回顾分析研究和应用版 2（MERRA-2）和热带降雨测量任务（TRMM）3B42 数据，研究了 1998-2013 年期间在韩国登陆的热带气旋（TC）的风和降雨区域。在这里，风和降雨区域分别定义为风速超过 14 m s-1 和降水率超过 80 mm day-1 的区域，距离 TC 中心 1000 km 以内。一般来说，TC 表现出明显的不对称风和降雨结构，在登陆期间韩国上空出现强烈的垂直风切变。降雨区域随着环境垂直风切变显著增加，而风区域对此不敏感。强垂直风切变和弱垂直风切变案例的综合分析证实，降雨区域的增加与垂直风切变引起的不对称对流（下风左侧上升/上升右侧下沉运动）有关。这项工作强调了当地大气环境在确定 TC 登陆期间主要受强风和强降雨影响的区域方面的重要性。
