气候变化领域集成服务门户(CCPortal): U.S. Extreme Precipitation Weather Types Increased in Frequency During the 20th Century

CCPortal

DOI	10.1029/2020JD034287
	U.S. Extreme Precipitation Weather Types Increased in Frequency During the 20th Century
	Prein A.F.; Mearns L.O.
发表日期	2021
ISSN	2169897X
卷号	126 期号:7
英文摘要	Extreme precipitation has increased in frequency and intensity across the Conterminous U.S. (CONUS). This trend is expected to continue under future climate change. The cause is a combination of thermodynamic (i.e., warmer temperatures increase the atmospheric moisture content) and dynamic changes (e.g., shifts in cyclone frequency and tracks). It is well-established that thermodynamic changes will intensify extreme precipitation events, but the impacts of dynamic changes are more uncertain. Extreme events are, per definition, rare and occur in unusual weather situations that are distinctly different from regular day-to-day weather. We take advantage of this and identify extreme precipitation-producing weather patterns (XWTs) for all major watersheds across the CONUS by using a novel algorithm. We show that a set of one to four XWTs per watershed are causing extreme precipitation accumulations. These XWTs can be detected based on their synoptic-scale fingerprint and are associated with West Coast atmospheric rivers, troughing in the desert Southwest, cutoff lows and troughs in the central and northwestern plains, and tropical cyclones along the Gulf and Atlantic coast. The algorithm is flexible enough to provide reliable results for city to major watershed-scales and can detect extremes that are unprecedented in the training record. Importantly, this approach allows us to assess long-term trends in extreme precipitation dynamics and reveal that XWT frequencies increased significantly in most U.S. watersheds during the 20th century indicating that changes in the atmospheric dynamics played an important role in historic extreme precipitation increases. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	climate change; extreme weather types; precipitation extremes; watersheds; weather patterns
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/185364
作者单位	National Center for Atmospheric Research, Boulder, CO, United States
推荐引用方式 GB/T 7714	Prein A.F.,Mearns L.O.. U.S. Extreme Precipitation Weather Types Increased in Frequency During the 20th Century[J],2021,126(7).
APA	Prein A.F.,&Mearns L.O..(2021).U.S. Extreme Precipitation Weather Types Increased in Frequency During the 20th Century.Journal of Geophysical Research: Atmospheres,126(7).
MLA	Prein A.F.,et al."U.S. Extreme Precipitation Weather Types Increased in Frequency During the 20th Century".Journal of Geophysical Research: Atmospheres 126.7(2021).