气候变化领域集成服务门户(CCPortal): A Distinct Atmospheric Mode for California Precipitation

CCPortal

DOI	10.1029/2020JD034403
	A Distinct Atmospheric Mode for California Precipitation
	Chen D.; Norris J.; Goldenson N.; Thackeray C.; Hall A.
发表日期	2021
ISSN	2169897X
卷号	126 期号:12
英文摘要	The hydrologic cycle in California is strongly influenced by wet-season (November–April) precipitation. Here, we demonstrate the existence of an influential mode of North Pacific atmospheric pressure variability that regulates wet-season precipitation variability over both northern and southern California. This mode, named as the “California precipitation mode” (CPM), is statistically distinct from other well-known modes of pressure variability such as the Pacific-North American pattern. In addition to controlling wet-season mean precipitation, positive days of the CPM coincide with up to 90% of the extreme (>99th percentile) precipitation days and 76% of detected atmospheric rivers (ARs) days, while the negative days correspond with 60% of the dry days. CMIP6 models capture the CPM remarkably well, including its statistical separation from the other well-known modes of pressure variability. The models also reproduce the CPM's strong association with California wet-season precipitation, giving confidence in the models’ dynamics relating to regional hydrologic extremes. However, the models also exhibit biases in regional hydrologic extremes. The CPM is a useful way to understand the origins of those biases and select the more credible models for further analysis: Models with unrealistically strong gradients in the CPM pressure pattern generally oversimulate larger wet extremes and produce excessively long dry intervals in the historical period. Thus the hydrologic biases can be traced to the particular aspects of North Pacific atmospheric dynamics. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	extreme events; precipitation; regional hydroclimate
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/185133
作者单位	Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA, United States
推荐引用方式 GB/T 7714	Chen D.,Norris J.,Goldenson N.,et al. A Distinct Atmospheric Mode for California Precipitation[J],2021,126(12).
APA	Chen D.,Norris J.,Goldenson N.,Thackeray C.,&Hall A..(2021).A Distinct Atmospheric Mode for California Precipitation.Journal of Geophysical Research: Atmospheres,126(12).
MLA	Chen D.,et al."A Distinct Atmospheric Mode for California Precipitation".Journal of Geophysical Research: Atmospheres 126.12(2021).