DOI: 10.1175/JCLI-D-13-00689.1
Scopus记录号: 2-s2.0-84961291806
论文题名: Stochastically generated North American megadroughts
作者: Stevenson S. ; Timmermann A. ; Chikamoto Y. ; Langford S. ; Dinezio P.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2015
卷: 28, 期: 5 起始页码: 1865
结束页码: 1880
语种: 英语
Scopus关键词: Atmospheric movements
; Atmospheric temperature
; Atmospheric thermodynamics
; Climate change
; Climate models
; Climatology
; Drought
; Surface waters
; Atmosphere-ocean interactions
; Atmospheric variability
; Climate variability
; Decadal variability
; Palmer drought severity indices
; Sea surface temperature (SST)
; Southeast United States
; Teleconnections
; Oceanography
; air-sea interaction
; climate forcing
; climate modeling
; climate variation
; decadal variation
; drought
; sea surface temperature
; teleconnection
; United States
英文摘要: The importance of interannual-to-decadal sea surface temperature (SST) influences on drought in the United States is examined using a suite of simulations conducted with the T31×3 resolution version of the NCAR Community Earth System Model (CESM1.0.3). The model captures tropical Pacific teleconnections to North American precipitation reasonably well, although orographic features are somewhat enhanced at higher resolution. The contribution of SST anomalies is isolated by comparing two idealized, 1000-yr CESM1.0.3 experiments: a fully coupled control and an atmosphere-only (CAM4) run forced with the SST climatology from the control. Droughts are identified using the Palmer Drought Severity Index (PDSI), which is computed over four U.S. regions from the CESM1.0.3 experiments and compared with the North American Drought Atlas (NADA). The CESM1.0.3 reproduces the persistence ofNADAdroughts quite well, although the model underestimates drought severity. Within the CESM1.0.3 framework, SST forcing does not significantly affect drought intensity or frequency of occurrence, even for very persistent ''megadroughts'' of 15 yr or more in length. In both the CESM1.0.3 and NADA, with the exception of the Southeast United States, droughts in all regions have intensities, persistence lengths, and occurrence frequencies statistically consistent with a red noise null hypothesis. This implies that SST forcing is not the dominant factor in generating drought and therefore that many decadal megadroughts are caused by a combination of internal atmospheric variability and coupling with the land surface, with SST anomalies playing only a secondary role. © 2015 American Meteorological Society. 资助项目: NOAA, National Oceanic and Atmospheric Administration
; NSF, National Oceanic and Atmospheric Administration
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/50636
Appears in Collections: 气候变化事实与影响
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作者单位: International Pacific Research Center, University of Hawai'i at Maanoa, Honolulu, HI, United States; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, United States
Recommended Citation:
Stevenson S.,Timmermann A.,Chikamoto Y.,et al. Stochastically generated North American megadroughts[J]. Journal of Climate,2015-01-01,28(5)