DOI: 10.1175/JCLI-D-13-00074.1
Scopus记录号: 2-s2.0-84892534487
论文题名: Impact of evapotranspiration on dry season climate in the Amazon forest
作者: Harper A. ; Baker I.T. ; Denning A.S. ; Randall D.A. ; Dazlich D. ; Branson M.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2014
卷: 27, 期: 2 起始页码: 574
结束页码: 591
语种: 英语
Scopus关键词: Amazon forests
; Biosphere models
; Drought tolerances
; Drying condition
; Ecosystem model
; Forest conservation
; Net radiation
; Sensible heat flux
; Agronomy
; Conservation
; Drought
; Ecosystems
; Evapotranspiration
; Forestry
; Heat flux
; Soil moisture
; Climate models
; atmosphere-biosphere interaction
; climate effect
; climatology
; cooling
; dry season
; ecosystem approach
; evapotranspiration
; moisture transfer
; rainfall
; tropical forest
; water stress
; Agronomy
; Conservation
; Drought
; Ecosystems
; Forestry
; Amazonia
英文摘要: Moisture recycling can be an important source of rainfall over the Amazon forest, but this process relies heavily upon the ability of plants to access soil moisture. Evapotranspiration (ET) in the Amazon is often maintained or even enhanced during the dry season, when net radiation is high. However, ecosystem models often over predict the dry season water stress. The authors removed unrealistic water stress in an ecosystem model [the Simple Biosphere Model, version 3 (SiB3)] and examined the impacts of enhanced ET on the dry season climate when coupled to aGCM. The "stressed" model experiences dry season water stress and limitations on ET, while the "unstressed" model has enhanced root water access and exhibits strong drought tolerance. During the dry season in the southeastern Amazon, SiB3 unstressed has significantly higher latent heat flux (LH) and lower sensible heat flux (SH) than SiB3 stressed. There are two competing impacts on the climate in SiB3 unstressed: cooling resulting fromlower SH andmoistening resulting from higher LH.During the average dry season, the cooling plays a larger role and the atmosphere is more statically stable, resulting in less precipitation than in SiB3 stressed. During dry season droughts, significantly higher LH in SiB3 unstressed is a necessary but not sufficient condition for stronger precipitation. The moistening effect of LHdominates when the Bowen ratio (BR 5 SH/LH) is >1.0 in SiB3 stressed and precipitation is up to 26% higher in SiB3 unstressed. An implication of this analysis is that forest conservation could enable theAmazon to copewith drying conditions in the future. © 2014 American Meteorological Society. 资助项目: U.S. Department of Energy
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51337
Appears in Collections: 气候变化事实与影响
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作者单位: College of Engineering, Mathematics, and Physical Sciences, University of Exeter, Exeter, Devon, United Kingdom; Department of Atmospheric Science, Colorado State University, Fort Collins, CO, United States
Recommended Citation:
Harper A.,Baker I.T.,Denning A.S.,et al. Impact of evapotranspiration on dry season climate in the Amazon forest[J]. Journal of Climate,2014-01-01,27(2)