DOI: 10.1175/JCLI-D-12-00186.1
Scopus记录号: 2-s2.0-84874807289
论文题名: The tropical precipitation response to orbital precession
作者: Merlis T.M. ; Schneider T. ; Bordoni S. ; Eisenman I.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 6 起始页码: 2010
结束页码: 2021
语种: 英语
Scopus关键词: Atmospheric circulation
; Atmospheric general circulation models
; Clausius-Clapeyron relationship
; Relevant nonlinearities
; Seasonal distributions
; Thermodynamic changes
; Thermodynamic mechanism
; Tropical precipitation
; Advection
; Climatology
; Dynamics
; Moisture
; Thermodynamics
; Lasers
; advection
; atmospheric circulation
; atmospheric general circulation model
; climate variation
; nonlinearity
; paleoclimate
; precipitation (climatology)
; proxy climate record
; relative humidity
; thermodynamics
; water budget
; water vapor
英文摘要: Orbital precession changes the seasonal distribution of insolation at a given latitude but not the annual mean. Hence, the correlation of paleoclimate proxies of annual-mean precipitation with orbital precession implies a nonlinear rectification in the precipitation response to seasonal solar forcing. It has previously been suggested that the relevant nonlinearity is that of the Clausius-Clapeyron relationship. Here it is argued that a different nonlinearity related to moisture advection by the atmospheric circulation is more important. When perihelion changes from one hemisphere's summer solstice to the other's in an idealized aquaplanet atmospheric general circulation model, annual-mean precipitation increases in the hemisphere with the brighter, warmer summer and decreases in the other hemisphere, in qualitative agreement with paleoclimate proxies that indicate such hemispherically antisymmetric climate variations. The rectification mechanism that gives rise to the precipitation changes is identified by decomposing the perturbation water vapor budget into "thermodynamic" and "dynamic" components. Thermodynamic changes (caused by changes in humidity with unchanged winds) dominate the hemispherically antisymmetric annual-mean precipitation response to precession in the absence of land-sea contrasts. The nonlinearity that enables the thermodynamic changes to affect annual-mean precipitation is a nonlinearity of moisture advection that arises because precessioninduced seasonal humidity changes correlate with the seasonal cycle in low-level convergence. This interpretation is confirmed using simulations inwhich the Clausius-Clapeyron relationship is explicitly linearized. The thermodynamic mechanism also operates in simulations with an idealized representation of land, although in these simulations the dynamic component of the precipitation changes is also important, adding to the thermodynamic precipitation changes in some latitudes and offsetting it in others. © 2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51942
Appears in Collections: 气候变化事实与影响
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作者单位: Princeton University, Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States; California Institute of Technology, Pasadena, CA, United States; Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA, United States
Recommended Citation:
Merlis T.M.,Schneider T.,Bordoni S.,et al. The tropical precipitation response to orbital precession[J]. Journal of Climate,2013-01-01,26(6)