摘要
The seasonal and diurnal variations of cloud systems are profoundly affected by the large-scale and local environments.In this study,a one-year-long simulation was conducted using a two-dimensional cloud-resolving model over the Eastern Tibetan Plateau(ETP)and two subregions of Eastern China:Southern East China and Central East China.Deep convective clouds(DCCs)rarely occur in the cold season over ETP,whereas DCCs appear in Eastern China throughout the year,and the ETP DCCs are approximately 20%−30%shallower than those over Eastern China.Most strong rainfall events(precipitation intensity,PI>2.5 mm h−1)in Eastern China are related to warm-season DCCs with ice cloud processes.Because of the high elevation of the ETP,the warm-season freezing level is lower than in Eastern China,providing favorable conditions for ice cloud processes.DCCs are responsible for the diurnal variations of warm-season rainfall in all three regions.Warm-season DCCs over the ETP have the greatest total cloud water content and frequency in the afternoon,resulting in an afternoon rainfall peak.In addition,rainfall events in the ETP also exhibit a nocturnal peak in spring,summer,and autumn due to DCCs.Strong surface heat fluxes around noon can trigger or promote DCCs in spring,summer,and autumn over the ETP but produce only cumulus clouds in winter due to the cold and dry environment.
基金
supported under the National Key R&D Program of China (Grant No.2017YFA0604001)
National Science Foundation of China(Grant Nos.42075067,41875071,41705118)
the Second Tibetan Plateau Scientific Expedition and Research (STEP) program (Grant No.2019QZKK0105)
Key research and Development Program of Anhui Province (Grant No.202004b 11020012)
China Scholarship Council
the Natural Science Foundation of Jiangsu Province (Grant No.BK20170945)
the Open Fund of Key Laboratory of Meteorology and Ecological Environment of Hebei Province
the National Center of Meteorology,Abu Dhabi,UAE under the UAE Research Program for Rain Enhancement Science
