Early last glacial maximum in the southern Central Andes reveals northward shift of the westerlies at similar to 39 ka

Zech, Roland; Zech, Jana; Kull, Christoph; Kubrik, Peter W.; Veit, Heinz (2011). Early last glacial maximum in the southern Central Andes reveals northward shift of the westerlies at similar to 39 ka. Climate of the past, 7(1), pp. 41-46. Göttingen: Copernicus Publications 10.5194/cp-7-41-2011

Preview

Text cp-7-41-2011.pdf - Published Version Available under License Creative Commons: Attribution (CC-BY). Download (1MB) | Preview

The latitudinal position of the southern westerlies has been suggested to be a key parameter for the climate on Earth. According to the general notion, the southern westerlies were shifted equatorward during the global Last Glacial Maximum (LGM: ~24–18 ka), resulting in reduced deep ocean ventilation, accumulation of old dissolved carbon, and low atmospheric CO2 concentrations. In order to test this notion, we applied surface exposure dating on moraines in the southern Central Andes, where glacial mass balances are particularly sensitive to changes in precipitation, i.e. to the latitudinal position of the westerlies. Our results provide robust evidence that the maximum glaciation occurred already at ~39 ka, significantly predating the global LGM. This questions the role of the westerlies for atmospheric CO2, and it highlights our limited understanding of the forcings of atmospheric circulation.

Interest & Impact

Downloads

120 since deposited on 04 Oct 2013
14 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item