DOI: 10.1175/JCLI-D-11-00067.1
Scopus记录号: 2-s2.0-84865190594
论文题名: Surface temperature gradients as diagnostic indicators of midlatitude circulation dynamics
作者: Karamperidou C. ; Cioffi F. ; Lall U.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2012
卷: 25, 期: 12 起始页码: 4154
结束页码: 4171
语种: 英语
Scopus关键词: Atmospheric circulation patterns
; Circulation patterns
; Colder climate
; Diagnostic aids
; Diagnostic indicators
; ENSO models
; Forcings
; Interannual
; Jet streams
; Joint distributions
; Low order models
; Midlatitudes
; Multistable
; Northern Hemispheres
; Secular trend
; Surface temperature gradient
; Temperature contrast
; Atmospheric temperature
; Climate change
; Dynamics
; Nickel compounds
; Probability distributions
; Surface properties
; Thermal gradients
; annual variation
; atmospheric circulation
; climate change
; climate forcing
; decadal variation
; El Nino-Southern Oscillation
; jet stream
; midlatitude environment
; Northern Hemisphere
; surface temperature
; temperature gradient
; warming
英文摘要: Zonal and meridional surface temperature gradients are considered to be determinants of large-scale atmospheric circulation patterns. However, there has been limited investigation of these gradients as diagnostic aids. Here, the twentieth-century variability in the Northern Hemisphere equator-to-pole temperature gradient (EPG) and the ocean-land temperature contrast (OLC) is explored. A secular trend in decreasing EPG and OLC is noted. Decadal and interannual (ENSO-related) variations in the joint distribution of EPGandOLCare identified, hinting at multistable climate states that may be indigenous to the climate or due to changing boundary forcings. The NH circulation patterns for cases in the tails of the joint distribution of EPG and OLC are also seen to be different. Given this context, this paper extends past efforts to develop insights into jet stream dynamics using the Lorenz-1984 model, which is forced directly and only by EPG and OLC. The joint probability distribution of jet stream and eddy energy, conditional on EPG and OLC scenarios, is investigated. The scenarios correspond to (i) warmer versus colder climate conditions and (ii) polarized ENSO phases. The latter scenario involves the use of a heuristic ENSO model to drive the Lorenz-1984 model via a modulation of the EPG or the OLC. As with GCMs, the low-order model reveals that the response to El Nin{ogonek}o forcing is not similar to an anthropogenic warming signature. The potential uses of EPG and OLC as macro-level indicators of climate change and variability and for comparing results across GCMs and observations are indicated. © 2012 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52369
Appears in Collections: 气候变化事实与影响
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作者单位: Columbia University, New York, NY, United States; University of Rome La Sapienza, Rome, Italy
Recommended Citation:
Karamperidou C.,Cioffi F.,Lall U.. Surface temperature gradients as diagnostic indicators of midlatitude circulation dynamics[J]. Journal of Climate,2012-01-01,25(12)