DOI: 10.1002/2017JD027888
Scopus记录号: 2-s2.0-85047450893
论文题名: Regional Hydroclimatic Variability Due To Contemporary Deforestation in Southern Amazonia and Associated Boundary Layer Characteristics
作者: Khanna J. ; Medvigy D. ; Fisch G. ; de Araújo Tiburtino Neves T.T.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2018
卷: 123, 期: 8 起始页码: 3993
结束页码: 4014
语种: 英语
英文关键词: Amazon
; deforestation
; dynamical circulation
; precipitation seasonality
; Rondônia
; surface roughness
Scopus关键词: atmospheric circulation
; atmospheric dynamics
; boundary layer
; deforestation
; hydrodynamics
; mesoscale meteorology
; numerical model
; precipitation (climatology)
; seasonality
; surface roughness
; wind velocity
; Amazonia
; Brazil
; Rondonia
; Nia
英文摘要: Amazonian deforestation causes systematic changes in regional dry season precipitation. Some of these changes at contemporary large scales (a few hundreds of kilometers) of deforestation have been associated with a “dynamical mesoscale circulation,” induced by the replacement of rough forest with smooth pasture. In terms of decadal averages, this dynamical mechanism yields increased precipitation in downwind regions and decreased precipitation in upwind regions of deforested areas. Daily, seasonal, and interannual variations in this phenomenon may exist but have not yet been identified or explained. This study uses observations and numerical simulations to develop relationships between the dynamical mechanism and the local- and continental-scale atmospheric conditions across a range of time scales. It is found that the strength of the dynamical mechanism is primarily controlled by the regional-scale thermal and dynamical conditions of the boundary layer and not by the continental- and global-scale atmospheric state. Lifting condensation level and wind speed within the boundary layer have large and positive correlations with the strength of the dynamical mechanism. The strength of these relationships depends on time scale and is strongest over the seasonal cycle. Overall, the dynamical mechanism is found to be strongest during times when the atmosphere is relatively stable. Hence, for contemporary large scales of deforestation this phenomenon is found to be the prevalent convective triggering mechanism during the dry and parts of transition seasons (especially during the dry-to-wet transition), significantly affecting the hydroclimate during this period. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114047
Appears in Collections: 气候减缓与适应
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作者单位: Program in Atmospheric and Oceanic Science, Princeton University, Princeton, NJ, United States; Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, United States; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States; Department of Aerospace Science and Technology, São José dos Campos, Brazil; Atmospheric Sciences, Federal University of West of Pará, Santarém, Brazil
Recommended Citation:
Khanna J.,Medvigy D.,Fisch G.,et al. Regional Hydroclimatic Variability Due To Contemporary Deforestation in Southern Amazonia and Associated Boundary Layer Characteristics[J]. Journal of Geophysical Research: Atmospheres,2018-01-01,123(8)