TY - JOUR
T1 - Localization and Invigoration of Mei-yu Front Rainfall due to Aerosol-Cloud Interactions
T2 - A Preliminary Assessment Based on WRF Simulations and IMFRE 2018 Field Observations
AU - Liu, Lin
AU - Cui, Chunguang
AU - Deng, Yi
AU - Zhou, Zhimin
AU - Hu, Yang
AU - Wang, Bin
AU - Ren, Jing
AU - Cai, Zhaoxin
AU - Bai, Yongqing
AU - Yang, Junmei
AU - Dong, Xiquan
N1 - Funding Information:
This work was supported by the National Key Research and Development Program of China under Grants 2016YFC0203304 and National Natural Science Foundation of China under Grants 41620104009, 41830965, and 41705034. Last but not least, special thanks go to the editor and anonymous reviewers for their insightful comments.
Publisher Copyright:
©2020. American Geophysical Union. All Rights Reserved.
PY - 2020/7/16
Y1 - 2020/7/16
N2 - Aerosol-cloud interactions remain a major source of uncertainty in our understanding and modeling of the Earth's hydrological cycle. Based upon a diagnostic and modeling analysis utilizing the latest field measurements from the Integrative Monsoon Frontal Rainfall Experiment (IMFRE) 2018, this paper reports the effects of aerosols on the cloud properties along the Mei-yu front over the Middle Reaches of Yangtze River in China. Numerical experiments with the Weather Research and Forecasting (WRF) model suggest that increasing aerosol number concentration reduces surface precipitation by ~8.8% and delays the onset of rainfall by ~30 min. Furthermore, warm clouds are suppressed but the convective cores are slightly intensified. This corresponds to an overall aerosol effect of “localization and invigoration” of the Mei-yu rainfall and thus an elevated probability of short-term heavy rainfall. The signals of “convective invigoration” with a bulk scheme in this study are relatively weak compared to those simulated by bin microphysics. The increased aerosol concentration strengthens Mei-yu front and changes local morphology of the front, consistent with earlier studies demonstrating positive effects of convective heating on the genesis and maintenance of Mei-yu front via conditional instability of the second kind (CISK) and diabatic generation of potential vorticity. Also discussed are the uncertainties of bulk microphysics in simulating aerosol-cloud interactions, which may shed light on the design of future field campaigns to further understand the impact of aerosol-cloud interactions on weather and climate over China in boreal summer.
AB - Aerosol-cloud interactions remain a major source of uncertainty in our understanding and modeling of the Earth's hydrological cycle. Based upon a diagnostic and modeling analysis utilizing the latest field measurements from the Integrative Monsoon Frontal Rainfall Experiment (IMFRE) 2018, this paper reports the effects of aerosols on the cloud properties along the Mei-yu front over the Middle Reaches of Yangtze River in China. Numerical experiments with the Weather Research and Forecasting (WRF) model suggest that increasing aerosol number concentration reduces surface precipitation by ~8.8% and delays the onset of rainfall by ~30 min. Furthermore, warm clouds are suppressed but the convective cores are slightly intensified. This corresponds to an overall aerosol effect of “localization and invigoration” of the Mei-yu rainfall and thus an elevated probability of short-term heavy rainfall. The signals of “convective invigoration” with a bulk scheme in this study are relatively weak compared to those simulated by bin microphysics. The increased aerosol concentration strengthens Mei-yu front and changes local morphology of the front, consistent with earlier studies demonstrating positive effects of convective heating on the genesis and maintenance of Mei-yu front via conditional instability of the second kind (CISK) and diabatic generation of potential vorticity. Also discussed are the uncertainties of bulk microphysics in simulating aerosol-cloud interactions, which may shed light on the design of future field campaigns to further understand the impact of aerosol-cloud interactions on weather and climate over China in boreal summer.
KW - Mei-yu front
KW - aerosol-cloud interactions
KW - microphysical properties
KW - thermodynamic and dynamic effects
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U2 - 10.1029/2019JD031952
DO - 10.1029/2019JD031952
M3 - Article
AN - SCOPUS:85087728434
SN - 2169-897X
VL - 125
JO - Journal of Geophysical Research Atmospheres
JF - Journal of Geophysical Research Atmospheres
IS - 13
M1 - e2019JD031952
ER -