Page 281 - 《高原气象》2025年第5期

5 期 张 磊等：基于GPM数据的华东地区中尺度对流系统宏微观结构特征研究 1399

A Study on Characteristics of Mesoscale Convective Systems

in East China Based on GPM Data

1
2
1
1， 2
ZHANG Lei ， DUAN Jing ， XU Cheng ， WANG Hui ， CHENG Ying ，
2
JIANG Shujie ， HUANG Xuanxuan 3
1
（1. Weather Modification Center of Zhejiang Province， Hangzhou 310051， Zhejiang， China；
2. CMA Cloud-Precipitation Physics and Weather Modification Key Laboratory， Beijing 100081， China；
3. Zhejiang Meteorological Observatory， Hangzhou 310051， Zhejiang， China）
Abstract： Based on GPM data from March 2014 to July 2023， the spatial and temporal distribution characteris‐
tic of mesoscale convective systems （MCSs） and sub-mesoscale convective systems （sub-MCSs） in East China
are studied. Then the macro and micro structure characteristics of MCSs and sub-MCSs are studied based on six
cases from June to August 2022 which classified by the area of systems. The results show that MCSs occur most
frequently in June. The magnitude of diurnal variation of MCSs is relatively flat， and the life history is longer.
The sub-MCSs occur most frequently in August. The period of 14:00 -15:00 （Beijing time） are the time when
sub-MCSs most likely occurring. The geographical distribution of convection is closely related to the topography.
The concentrated distribution area of MCSs in summer has a trend of changing from south region to north region.
The sub-MCSs mainly distributed in Fujian and Zhejiang Province and mountainous area in Jiangxi Province in
summer. According to precipitation types， MCSs and sub-MCSs can be divided into convective precipitation，
stratiform precipitation and other precipitation. The particle concentration of convective precipitation in MCSs is
lower than that of stratiform precipitation in general， but the particle size is larger. The average near-surface rain‐
fall rate of convective precipitation in MCSs is almost four to five times as much as the stratiform precipitation.
The particle size of sub-MCSs dominated by convective precipitation is as much as convective precipitation in
MCSs， but the particle concentration is much lower， which leads to the average near-surface rainfall rate of sub-
MCSs is much lower than that of convective precipitation in MCSs. Precipitation intensity is determined by many
factors such as particle size and particle concentration. The precipitation particle size increases when descending
form the air above 5 km altitude and the growth rate of convective precipitation is stronger than that of stratiform
precipitation. The precipitation particle size decreases when descending form the air below 4 km altitude. The par‐
ticle concentration of stratiform precipitation has no significant change when descending， while the convective
precipitation is generally associated with the increase of particle concentration.
Key words： GPM； East China； MCSs； cloud physical characteristics； spatial and temporal distribution