气候变化领域集成服务门户(CCPortal): A new mechanism for millennial scale positive precipitation anomalies over tropical South America

CCPortal

DOI	10.1016/j.quascirev.2019.105990
	A new mechanism for millennial scale positive precipitation anomalies over tropical South America
	Campos M.C.; Chiessi C.M.; Prange M.; Mulitza S.; Kuhnert H.; Paul A.; Venancio I.M.; Albuquerque A.L.S.; Cruz F.W.; Bahr A.
发表日期	2019
ISSN	0277-3791
卷号	225
英文摘要	Continental and marine paleoclimate archives from northwestern and northeastern South America recorded positive precipitation anomalies during Heinrich Stadials (HS). These anomalies have been classically attributed to enhanced austral summer (monsoon) precipitation. However, the lack of marine paleoclimate records off eastern South America as well as inconsistencies between southeastern South American continental and marine records hamper a comprehensive understanding of the mechanism responsible for (sub-) tropical South American hydroclimate response to HS. Here we investigate piston core M125-95-3 collected off eastern South America (10.94°S) and simulate South American HS conditions with a high-resolution version of an atmosphere-ocean general circulation model. Further, meridional changes in precipitation over (sub-) tropical South America were assessed with a thorough compilation of previously available marine paleorecords. Our ln(Ti/Ca) and ln(Fe/K) data show increases during HS6-Younger Dryas. It is the first core off eastern South America and the southernmost from the Atlantic continental margin of South America that unequivocally records HS-related positive precipitation anomalies. Based on our new data, model results and the compilation of available marine records, we propose a new mechanism for the positive precipitation anomalies over tropical South America during HS. The new mechanism involves austral summer precipitation increases only over eastern South America while the rest of tropical South America experienced precipitation increases during the winter, challenging the widely held assumption of a strengthened monsoon. South American precipitation changes were triggered by dynamic and thermodynamic processes including a stronger moisture supply from the equatorial North Atlantic (tropical South Atlantic) in austral winter (summer). © 2019 Elsevier Ltd
英文关键词	Heinrich Stadials; Inorganic geochemistry; Paleoclimatology; Precipitation; Quaternary; South America; X-ray fluorescence
语种	英语
scopus关键词	Atmospheric thermodynamics; Precipitation (chemical); Heinrich Stadials; Inorganic geochemistries; Paleoclimatology; Quaternary; South America; X ray fluorescence; Tropics; continental margin; geochemistry; Heinrich event; inorganic compound; paleoclimate; precipitation intensity; Quaternary; X-ray fluorescence; Atlantic Ocean; Atlantic Ocean (North); Atlantic Ocean (South); South America
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151706
作者单位	School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil; MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany; Center for Weather Forecasting and Climate Studies (CPTEC), National Institute for Space Research (INPE), Cachoeira Paulista, Brazil; Graduate Program in Geochemistry, Fluminense Federal University, Niterói, Brazil; Institute of Geociences, University of São Paulo, São Paulo, Brazil; Institute of Earth Sciences, Heidelberg University, Heidelberg, Germany
推荐引用方式 GB/T 7714	Campos M.C.,Chiessi C.M.,Prange M.,et al. A new mechanism for millennial scale positive precipitation anomalies over tropical South America[J],2019,225.
APA	Campos M.C..,Chiessi C.M..,Prange M..,Mulitza S..,Kuhnert H..,...&Bahr A..(2019).A new mechanism for millennial scale positive precipitation anomalies over tropical South America.Quaternary Science Reviews,225.
MLA	Campos M.C.,et al."A new mechanism for millennial scale positive precipitation anomalies over tropical South America".Quaternary Science Reviews 225(2019).