气候变化领域集成服务门户(CCPortal): U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability

CCPortal

DOI	10.1175/JCLI-D-20-0365.1
	U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability
	Baek S.H.; Smerdon J.E.; Cook B.I.; Williams A.P.
发表日期	2021
ISSN	08948755
起始页码	1947
结束页码	1962
卷号	34 期号:5
英文摘要	Droughts that span the states of Washington, Oregon, and California are rare but devastating due to their large spatial coverage and potential loss of redundancies in water, agricultural, and fire-fighting resources. Such pan-coastal droughts [which we define using boreal summer volumetric soil moisture along the U.S. Pacific coast (328-508N, 1158-1278W)] require a more precise understanding of the roles played by the Pacific Ocean and internal atmospheric variability. We employ 16-member ensembles of the Community Atmosphere Model version 5 and Community Climate Model version 3 forced with observed sea surface temperatures (SSTs) from 1856 to 2012 to separate and quantify the influences of the tropical Pacific and internal atmospheric variability on pan-coastal droughts; all other boundary conditions are kept at climatological levels to explicitly isolate for the impacts of SST changes. Internal atmospheric variability is the dominant driver of pan-coastal droughts, accounting for 84% of their severity, and can reliably generate pan-coastal droughts even when ocean conditions do not favor drought. Cold phases of the Pacific Ocean play a secondary role and contribute, on average, only 16% to pan-coastal drought severity. Spatiotemporal analyses of precipitation and soil moisture along the U.S. Pacific coast corroborate these findings and identify an antiphased wet-dry dipole pattern induced by the Pacific to play a more secondary role. Our model framework expands on previous observational analyses that point to the spatially uniform forcing of internal atmospheric variability as the more dominant mode of hydroclimate variability along the U.S. Pacific coast. The secondary nature of oceanic forcing suggests limited predictability of pan-continental droughts. © 2021 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).
英文关键词	Atmosphere-ocean interaction; Drought; Hydrology
语种	英语
scopus关键词	Agricultural robots; Climate models; Drought; Fire extinguishers; Soil moisture; Surface waters; Atmospheric variability; Community atmosphere model; Community climate models; Observational analysis; Ocean conditions; Sea surface temperatures; Spatiotemporal analysis; Volumetric soil moistures; Oceanography; air-sea interaction; atmospheric circulation; coastal zone; drought; hydrological response; precipitation assessment; sea surface temperature; spatiotemporal analysis; Pacific Coast [North America]; Pacific Coast [United States]; United States; Washington [United States]
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/178692
作者单位	Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; Department of Earth and Environmental Sciences, Columbia University, New York, NY, United States; NASA Goddard Institute for Space Studies, New York, NY, United States
推荐引用方式 GB/T 7714	Baek S.H.,Smerdon J.E.,Cook B.I.,et al. U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability[J],2021,34(5).
APA	Baek S.H.,Smerdon J.E.,Cook B.I.,&Williams A.P..(2021).U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability.Journal of Climate,34(5).
MLA	Baek S.H.,et al."U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability".Journal of Climate 34.5(2021).