气候变化领域集成服务门户(CCPortal): Trends in Diurnal Cycle of Summertime Rainfall Over Coastal South China in the Past 135 Years: Characteristics and Possible Causes

CCPortal

DOI	10.1029/2020JD033621
	Trends in Diurnal Cycle of Summertime Rainfall Over Coastal South China in the Past 135 Years: Characteristics and Possible Causes
	Su L.; Fung J.C.H.; Li J.; Wong W.K.
发表日期	2021
ISSN	2169897X
卷号	126 期号:8
英文摘要	The interdecadal changes in the diurnal cycle of summertime rainfall over coastal South China (CSC) were analyzed for the period of 1884–2018. The results revealed that rainfall intensity has increased with the decrease of occurrence frequency during both pre- and mid-summer in the past 135 years. During the most recent 40 years, occurrence frequency and intensity of nocturnal rainfall, especially extreme rainfall, have substantially increased over CSC, whereas those of daytime extreme rainfall have decreased. Different increasing rates of near-surface temperature over land and sea are the main contributors to the distinct trends of daytime and nocturnal extreme rainfall. During daytime, a higher increasing rate of near-surface temperature over sea results in a smaller temperature gradient along the coast, leading to a less convective atmosphere. This negates the effect of increased air-temperature over CSC in both pre- and mid-summer. In contrast, during nighttime, a higher increasing rate of near-surface temperature over sea results in a greater temperature gradient along the coast, leading to stronger low-level offshore winds and more convective layers over coastal waters. During pre-summer, the stronger nocturnal low-level offshore winds meets the warm and moist monsoonal flows, substantially enhancing nocturnal extreme rainfall along the coast. In mid-summer, more vigorous upward motions over coastal waters of CSC enhance convective activities during nighttime, which also lead to an intensification of nocturnal rainfall. The most significant increase and intensification of extreme rainfall is observed in western CSC during pre-summer, where the land-sea difference of near-surface temperature is the greatest over CSC. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	coastal South China; diurnal cycle; long-term trend; precipitation
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185376
作者单位	School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai, China; Key Laboratory of Tropical Atmosphere–Ocean System, Ministry of Education, Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China; Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong; Department of Mathematics, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong; Hong Kong Observatory, Hong Kong, Hong Kong
推荐引用方式 GB/T 7714	Su L.,Fung J.C.H.,Li J.,et al. Trends in Diurnal Cycle of Summertime Rainfall Over Coastal South China in the Past 135 Years: Characteristics and Possible Causes[J],2021,126(8).
APA	Su L.,Fung J.C.H.,Li J.,&Wong W.K..(2021).Trends in Diurnal Cycle of Summertime Rainfall Over Coastal South China in the Past 135 Years: Characteristics and Possible Causes.Journal of Geophysical Research: Atmospheres,126(8).
MLA	Su L.,et al."Trends in Diurnal Cycle of Summertime Rainfall Over Coastal South China in the Past 135 Years: Characteristics and Possible Causes".Journal of Geophysical Research: Atmospheres 126.8(2021).