DOI: 10.1016/j.quascirev.2013.03.019
Scopus记录号: 2-s2.0-84885179959
论文题名: An enhanced role for the Tropical Pacific on the humid Pleistocene-Holocene transition in southwestern North America
作者: Antinao J.L. ; McDonald E.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 78 起始页码: 319
结束页码: 341
语种: 英语
英文关键词: Millennial scale climate change
; Moisture sources
; Pleistocene-Holocene transition
; Southwestern North America
; Tropical Pacific
Scopus关键词: Circulation patterns
; Extra-tropical cyclones
; Late Pleistocene-Holocene
; Moisture sources
; Pleistocene-Holocene transition
; Southwestern North America
; Tropical Pacific
; Winter precipitation
; Atmospheric thermodynamics
; Climate change
; Landforms
; Moisture
; Sedimentation
; Storms
; Vegetation
; Tropics
; aggradation
; alluvial fan
; climate effect
; El Nino
; Holocene
; humid tropics
; landscape evolution
; monsoon
; paleobotany
; paleoclimate
; Pleistocene
; precipitation (climatology)
; tropical cyclone
; vegetation dynamics
; winter
; North America
; Pacific Ocean
; Pacific Ocean (Tropical)
英文摘要: Climate effects on landscape evolution during the Late Pleistocene-Holocene transition (~14.6-8ka) in southwestern North America traditionally are linked to the activity of the North American Monsoon and to vegetation change related to a decrease in winter precipitation acting in response to orbital cyclicity. We performed an integrated analysis of regional alluvial fan, lacustrine and paleobotanical records for the area comparing them with hemispheric and regional paleoclimate proxies. Our focus was on the potential role the Tropical Pacific has as a synoptic pattern modulator and moisture source for hydrogeomorphic activity in the region.Our analysis indicates that the onset of alluvial fan aggradation in most of the region at ~13.5ka could have been a response to semi-permanent El Niño-like conditions in the Tropical Pacific, which enhanced the frequency of winter frontal storms as well as increased penetration of tropical cyclones in the region. The North American Monsoon was restricted in extent and intensity until ~7ka and probably was not a major factor in alluvial fan aggradation. A second stage of alluvial fan aggradation from 11.5 to ~9ka was dominated by hyper-concentrated flows and sheet-flood sedimentation, along with deposition in fluvial settings. Storms were probably were linked to landfall of enhanced water vapor bands in the leading edge of winter extra-tropical cyclones with moisture advected directly from the Tropical Pacific. At~8ka, favorable conditions for the occurrence of these storms waned and storm tracks shifted northward.Analysis of modern analogs for storm types described above as prevalent during this period indicates that changes in circulation patterns across the Tropical Pacific can affect storm properties enough to explain the observed geomorphic effects, regardless of other factors traditionally considered of large impact like vegetation change. Our results suggest that the Tropical Pacific plays a larger role than currently thought in landscape evolution of the region. © 2013 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60496
Appears in Collections: 过去全球变化的重建
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作者单位: Division of Earth and Ecosystem Sciences, Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, United States
Recommended Citation:
Antinao J.L.,McDonald E.. An enhanced role for the Tropical Pacific on the humid Pleistocene-Holocene transition in southwestern North America[J]. Quaternary Science Reviews,2013-01-01,78