气候变化领域集成服务门户(CCPortal): Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: A multi-proxy intercomparison study

CCPortal

DOI	10.5194/cp-16-2459-2020
	Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: A multi-proxy intercomparison study
	Vorrath M.-E.; Müller J.; Rebolledo L.; Cárdenas P.; Shi X.; Esper O.; Opel T.; Geibert W.; Munoz P.; Haas C.; Kuhn G.; Lange C.B.; Lohmann G.; Mollenhauer G.
发表日期	2020
ISSN	1814-9324
卷号	16 期号:6
英文摘要	In the last decades, changing climate conditions have had a severe impact on sea ice at the western Antarctic Peninsula (WAP), an area rapidly transforming under global warming. To study the development of spring sea ice and environmental conditions in the pre-satellite era we investigated three short marine sediment cores for their biomarker inventory with a particular focus on the sea ice proxy IPSO25 and micropaleontological proxies. The core sites are located in the Bransfield Strait in shelf to deep basin areas characterized by a complex oceanographic frontal system, coastal influence and sensitivity to large-scale atmospheric circulation patterns. We analyzed geochemical bulk parameters, biomarkers (highly branched isoprenoids, glycerol dialkyl glycerol tetraethers, sterols), and diatom abundances and diversity over the past 240 years and compared them to observational data, sedimentary and ice core climate archives, and results from numerical models. Based on biomarker results we identified four different environmental units characterized by (A) low sea ice cover and high ocean temperatures, (B) moderate sea ice cover with decreasing ocean temperatures, (C) high but variable sea ice cover during intervals of lower ocean temperatures, and (D) extended sea ice cover coincident with a rapid ocean warming. While IPSO25 concentrations correspond quite well to satellite sea ice observations for the past 40 years, we note discrepancies between the biomarker-based sea ice estimates, the long-term model output for the past 240 years, ice core records, and reconstructed atmospheric circulation patterns such as the El Niño-Southern Oscillation (ENSO) and Southern Annular Mode (SAM). We propose that the sea ice biomarker proxies IPSO25 and PIPSO25 are not linearly related to sea ice cover, and, additionally, each core site reflects specific local environmental conditions. High IPSO25 and PIPSO25 values may not be directly interpreted as referring to high spring sea ice cover because variable sea ice conditions and enhanced nutrient supply may affect the production of both the sea-ice-associated and phytoplankton-derived (open marine, pelagic) biomarker lipids. For future interpretations we recommend carefully considering individual biomarker records to distinguish between cold sea-ice-favoring and warm seaice- diminishing environmental conditions. © 2020 BMJ Publishing Group. All rights reserved.
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/183629
作者单位	Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany; MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany; Department of Geosciences, University of Bremen, Germany; Centro de Investigación Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile; Instítuto Antártico Chileno (INACH), Punta Arenas, Chile; Facultad de Ciencias Del Mar, Universidad Católica Del Norte, Coquimbo, Chile; Centro Oceanográfico COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile; Departamento de Oceanografía, Universidad de Concepción, Chile; Scripps Institution of Oceanography, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, San diego, CA 92037, United States
推荐引用方式 GB/T 7714	Vorrath M.-E.,Müller J.,Rebolledo L.,et al. Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: A multi-proxy intercomparison study[J],2020,16(6).
APA	Vorrath M.-E..,Müller J..,Rebolledo L..,Cárdenas P..,Shi X..,...&Mollenhauer G..(2020).Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: A multi-proxy intercomparison study.Climate of the Past,16(6).
MLA	Vorrath M.-E.,et al."Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: A multi-proxy intercomparison study".Climate of the Past 16.6(2020).