DOI: 10.5194/cp-15-41-2019
Scopus记录号: 2-s2.0-85059880558
论文题名: Comparing the spatial patterns of climate change in the 9th and 5th millenniaBP from TRACE-21 model simulations
作者: Ning L. ; Liu J. ; Bradley R.S. ; Yan M.
刊名: Climate of the Past
ISSN: 18149324
出版年: 2019
卷: 15, 期: 1 起始页码: 41
结束页码: 52
语种: 英语
Scopus关键词: anomaly
; climate variation
; discharge
; intertropical convergence zone
; meltwater
; meridional circulation
; model
; Neoglacial
; Northern Hemisphere
; precipitation (climatology)
; sea surface temperature
; simulation
; Southern Hemisphere
; spatial distribution
; teleconnection
; Atlantic Ocean
; Atlantic Ocean (North)
; Eurasia
; Iceland
; South America
英文摘要: The spatial patterns of global temperature and precipitation changes, as well as corresponding large-scale circulation patterns during the latter part of the 9th and 5th millenniaBP (4800-4500 versus 4500-4000BP and 9200-8800 versus 8800-8000BP) are compared through a group of transient simulations using the Community Climate System Model version 3 (CCSM3). Both periods are characterized by significant sea surface temperature (SST) decreases over the North Atlantic, south of Iceland. Temperatures were also colder across the Northern Hemisphere but warmer in the Southern Hemisphere. Significant precipitation decreases are seen over most of the Northern Hemisphere, especially over Eurasia and the Asian monsoon regions, indicating a weaker summer monsoon. Large precipitation anomalies over northern South America and adjacent ocean regions are related to a southward displacement of the Intertropical Convergence Zone (ITCZ) in that region. Climate changes in the late 9th millenniumBP (the "8.2ka event") are widely considered to have been caused by a large freshwater discharge into the northern Atlantic, which is confirmed in a meltwater forcing sensitivity experiment, but this was not the cause of changes occurring between the early and latter halves of the 5th millenniumBP. Model simulations suggest that a combination of factors, led by long-term changes in insolation, drove a steady decline in SSTs across the North Atlantic and a reduction in the North Atlantic Meridional Overturning Circulation (AMOC), over the past 4500 years, with associated teleconnections across the globe, leading to drought in some areas. Multi-century-scale fluctuations in SSTs and AMOC strength were superimposed on this decline. This helps explain the onset of neoglaciation around 5000-4500BP, followed by a series of neoglacial advances and retreats during recent millennia. The "4.2kaBP Event" appears to have been one of several late Holocene multi-century fluctuations that were embedded in the long-term, low-frequency change in climate that occurred after ĝ1/44.8 ka. Whether these multi-century fluctuations were a response to internal centennial-scale ocean-atmosphere variability or external forcing (such as explosive volcanic eruptions and associated feedbacks) or a combination of such conditions is not known and requires further study. © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/122256
Appears in Collections: 气候变化事实与影响
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作者单位: Key Laboratory of Virtual Geographic Environment, Ministry of Education, State Key Laboratory of Geographical Environment Evolution, Jiangsu Provincial Cultivation Base, School of Geographical Science, Nanjing Normal University, Nanjing, China; Jiangsu Center for Collaborative Innovation in Geographical, Information Resource Development and Application, Nanjing, China; Climate System Research Center, Department of Geosciences, University of Massachusetts, Amherst, MA, United States
Recommended Citation:
Ning L.,Liu J.,Bradley R.S.,et al. Comparing the spatial patterns of climate change in the 9th and 5th millenniaBP from TRACE-21 model simulations[J]. Climate of the Past,2019-01-01,15(1)