气候变化领域集成服务门户(CCPortal): Giant dust particles at Nevado Illimani: A proxy of summertime deep convection over the Bolivian Altiplano

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DOI	10.5194/tc-15-1383-2021
	Giant dust particles at Nevado Illimani: A proxy of summertime deep convection over the Bolivian Altiplano
	Lindau F.G.L.; Simões J.C.; Delmonte B.; Ginot P.; Baccolo G.; Paleari C.I.; Di Stefano E.; Korotkikh E.; Introne D.S.; Maggi V.; Garzanti E.; Andò S.
发表日期	2021
ISSN	19940416
起始页码	1383
结束页码	1397
卷号	15 期号:3
英文摘要	A deeper understanding of past atmospheric circulation variability in the Central Andes is a high-priority topic in paleoclimatology mainly because of the necessity to validate climate models used to predict future precipitation trends and to develop mitigation and/or adaptation strategies for future climate change scenarios in this region.Within this context, we here investigate an 18-year firn core drilled at Nevado Illimani in order to interpret its mineral dust record in relation to seasonal processes, in particular atmospheric circulation and deep convection. The core was dated by annual layer counting based on seasonal oscillations of dust, calcium, and stable isotopes. Geochemical and mineralogical data show that dust is regionally sourced in winter and summer. During austral summer (wet season), an increase in the relative proportion of giant dust particles (20 um) is observed, in association with oscillations of stable isotope records (D, 18O). It seems that at Nevado Illimani both the deposition of dust and the isotopic signature of precipitation are influenced by atmospheric deep convection, which is also related to the total amount of precipitation in the area. This hypothesis is corroborated by regional meteorological data. The interpretation of giant particle and stable isotope records suggests that downdrafts due to convective activity promote turbulent conditions capable of suspending giant particles in the vicinity of Nevado Illimani. Giant particles and stable isotopes, when considered together, can be therefore used as a new proxy for obtaining information about deep convective activity in the past. © 2021 Copernicus GmbH. All rights reserved.
英文关键词	atmospheric convection; atmospheric deposition; climate change; climate oscillation; dust; mineral dust; paleoclimate; paleoenvironment; precipitation (climatology); proxy climate record; stable isotope; summer; Altiplano; Andes; Bolivia; Illimani; La Paz [Bolivia]
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202364
作者单位	Centro Polar e Climático, Universidade Federal do Rio Grande do sul, Porto Alegre, 91501-970, Brazil; Climate Change Institute, University of Maine, Orono, ME 04469, United States; Department of Environmental and Earth Sciences, University of Milano-Bicocca, Milan, 20126, Italy; Univ. Grenoble Alpes, CNRS, Ird, Grenoble INP, Ige, Grenoble, 38000, France
推荐引用方式 GB/T 7714	Lindau F.G.L.,Simões J.C.,Delmonte B.,et al. Giant dust particles at Nevado Illimani: A proxy of summertime deep convection over the Bolivian Altiplano[J],2021,15(3).
APA	Lindau F.G.L..,Simões J.C..,Delmonte B..,Ginot P..,Baccolo G..,...&Andò S..(2021).Giant dust particles at Nevado Illimani: A proxy of summertime deep convection over the Bolivian Altiplano.Cryosphere,15(3).
MLA	Lindau F.G.L.,et al."Giant dust particles at Nevado Illimani: A proxy of summertime deep convection over the Bolivian Altiplano".Cryosphere 15.3(2021).