TY - JOUR
T1 - Cloud and Precipitation Properties of MCSs Along the Meiyu Frontal Zone in Central and Southern China and Their Associated Large-Scale Environments
AU - Cui, Wenjun
AU - Dong, Xiquan
AU - Xi, Baike
AU - Liu, Min
N1 - Funding Information:
The Integrative Monsoon Frontal Rainfall Experiment (IMFRE) was supported by the National Natural Science Foundation of China (under Grant 41620104009). The researchers at the University of Arizona were supported by the Climate Model Development and Validation (CMDV) program funded by the Office of Biological and Environmental Research in the U.S. Department of Energy Office of Science under Grant DE-SC0017015 at the University of Arizona. We thank Xiaofang Wang from IHR for providing the radar reflectivity data. The IMERG products can be downloaded online (from https://pmm.nasa.gov/data-access/downloads/gpm). The globally merged IR product can be found at the GES DISC website (https://disc.gsfc.nasa.gov/datasets/GPM_MERGIR_1/summary). The MERRA-2 reanalysis data can be downloaded online (from https://disc.gsfc.nasa.gov/datasets?keywords=%22MERRA-2%22&page=1&source=Models%2FAnalyses%20MERRA-2). The IHR 3D mosaic radar reflectivity can be accessed online (from http://doi.org/10.5281/zenodo.3697233).
Publisher Copyright:
©2020. American Geophysical Union. All Rights Reserved.
PY - 2020/3/27
Y1 - 2020/3/27
N2 - This study focuses on investigating the cloud and precipitation features of Meiyu mesoscale convective systems (MCSs) and their relation to the large-scale environments in central and southern China using satellite observations and reanalysis data during the period 2014–2018. MCSs from two different locations, the Yangtze River Basin (YRB) and Southern China (SC), are examined separately. The Meiyu MCSs have a mean precipitation rate of 3.6 mm/hr and contribute 20% to 60% of the total precipitation during the Meiyu period. The diurnal cycle of Meiyu MCSs shows a maximum precipitation amount in the morning, which is associated with the enhanced nocturnal low-level jet (LLJ) overnight. Although the synoptic setups in YRB and SC are found to be similar when normalized around the MCS initiation locations, MCSs exhibit some differences in terms of the cloud top height, precipitation rate, and duration, which are likely by the differences in the local forcing. Large interannual variations are found in MCSs' number, cloud size, lifetime, and rainfall intensity, which is found to be associated with the interannual variabilities in the large-scale environments. By comparing the large-scale environments with climatological mean states, we find that the year with the most intense MCS activity during the study period is characterized by an intensified southwesterly LLJ, which increases the moisture transport from the Indian Ocean and an enhancement of the midtropospheric westerly jet, which induces adiabatic ascent along the Meiyu front, creating more favorable conditions for convection.
AB - This study focuses on investigating the cloud and precipitation features of Meiyu mesoscale convective systems (MCSs) and their relation to the large-scale environments in central and southern China using satellite observations and reanalysis data during the period 2014–2018. MCSs from two different locations, the Yangtze River Basin (YRB) and Southern China (SC), are examined separately. The Meiyu MCSs have a mean precipitation rate of 3.6 mm/hr and contribute 20% to 60% of the total precipitation during the Meiyu period. The diurnal cycle of Meiyu MCSs shows a maximum precipitation amount in the morning, which is associated with the enhanced nocturnal low-level jet (LLJ) overnight. Although the synoptic setups in YRB and SC are found to be similar when normalized around the MCS initiation locations, MCSs exhibit some differences in terms of the cloud top height, precipitation rate, and duration, which are likely by the differences in the local forcing. Large interannual variations are found in MCSs' number, cloud size, lifetime, and rainfall intensity, which is found to be associated with the interannual variabilities in the large-scale environments. By comparing the large-scale environments with climatological mean states, we find that the year with the most intense MCS activity during the study period is characterized by an intensified southwesterly LLJ, which increases the moisture transport from the Indian Ocean and an enhancement of the midtropospheric westerly jet, which induces adiabatic ascent along the Meiyu front, creating more favorable conditions for convection.
KW - MCS precipitation
KW - Meiyu rainfall
KW - extreme precipitation
UR - http://www.scopus.com/inward/record.url?scp=85082327493&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85082327493&partnerID=8YFLogxK
U2 - 10.1029/2019JD031601
DO - 10.1029/2019JD031601
M3 - Article
AN - SCOPUS:85082327493
SN - 2169-897X
VL - 125
JO - Journal of Geophysical Research Atmospheres
JF - Journal of Geophysical Research Atmospheres
IS - 6
M1 - e2019JD031601
ER -