Changes in Holocene climate and the intensity of Southern Hemisphere Westerly Winds based on a high-resolution palynological record from sub-Antarctic South Georgia

Strother, Stephanie L.; Salzmann, Ulrich; Roberts, Stephen J. ORCID: https://orcid.org/0000-0003-3407-9127; Hodgson, Dominic A. ORCID: https://orcid.org/0000-0002-3841-3746; Woodward, John; Van Nieuwenhuyze, Wim; Verleyen, Elie; Wyverman, Wim; Moreton, Steven G.. 2015 Changes in Holocene climate and the intensity of Southern Hemisphere Westerly Winds based on a high-resolution palynological record from sub-Antarctic South Georgia. The Holocene, 25 (2). 263-279. 10.1177/0959683614557576

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Abstract/Summary

Sub-Antarctic South Georgia is a key region for studying climate variability in the Southern Hemisphere, because of its position at the core of the Southern Hemisphere Westerly Wind belt and between the Antarctic Circumpolar Current and the Polar Frontal Zone. Here, we present a 5.8-m long high-resolution pollen record from Fan Lake on Annenkov Island dominated by local sub-polar vegetation, with Acaena and Poaceae being present throughout the last 7000 years. Palynological and sedimentological analyses revealed a warm late Holocene ‘climate optimum’ between 3790 and 2750 cal. yr BP, which was followed by a gradual transition to cool and wet conditions. This cooling was interrupted by slightly warmer environmental conditions between 1670 and 710 cal. yr BP that partly overlap with the Northern Hemisphere ‘Medieval Climate Anomaly’. Increases in non-native and long-distance pollen grains transported from South America (e.g. Nothofagus, Podocarpus) indicate that stronger Southern Hemisphere Westerly Winds over South Georgia possibly occurred during some ‘colder’ phases of the late Holocene, most notably between c. 2210 and 1670 cal. yr BP and after 710 cal. yr BP.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1177/0959683614557576
Programmes:	BAS Programmes > BAS Programmes 2015 > Palaeo-Environments, Ice Sheets and Climate Change
ISSN:	0959-6836
Additional Keywords:	Holocene, palynology, South Georgia, vegetation
Date made live:	08 Dec 2014 10:39 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/508446

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1177/0959683614557576

Programmes:

BAS Programmes > BAS Programmes 2015 > Palaeo-Environments, Ice Sheets and Climate Change

ISSN:

0959-6836

Additional Keywords:

Holocene, palynology, South Georgia, vegetation

Date made live:

08 Dec 2014 10:39 +0 (UTC)