Holden, P. B.; Edwards, N. R.; Wolff, E. W.; Lang, N. J.; Singarayer, J. S.; Valdes, P. J. and Stocker, T. F.
PDF (Accepted Manuscript)
- Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
|DOI (Digital Object Identifier) Link:||https://doi.org/10.5194/cp-6-431-2010|
|Google Scholar:||Look up in Google Scholar|
Ice core evidence indicates that even though atmospheric CO2 concentrations did not exceed ~300 ppm at any point during the last 800,000 years, East Antarctica was at least ~3-4ÂºC warmer than preindustrial (CO2 ~280 ppm) in each of the last four interglacials. During the previous three interglacials, this anomalous warming was short lived (~3,000 years) and apparently occurred before the completion of Northern Hemisphere deglaciation. Hereafter, we refer to these periods as 'Warmer than Present Transients' (WPTs). We present a series of experiments to investigate the impact of deglacial meltwater on the Atlantic Meridional Overturning Circulation (AMOC) and Antarctic temperature. It is well known that a slowed AMOC would increase southern sea surface temperature (SST) through the bipolar seesaw and observational data suggests that the AMOC remained weak throughout the terminations preceding WPTs, strengthening rapidly at a time which coincides closely with peak Antarctic temperature. We present two 800 kyr transient simulations using the Intermediate Complexity model GENIE-1 which demonstrate that meltwater forcing generates transient southern warming that is consistent with the timing of WPTs, but is not sufficient (in this single parameterisation) to reproduce the magnitude of observed warmth. In order to investigate model and boundary condition uncertainty, we present three ensembles of transient GENIE-1 simulations across Termination II (135,000 to 124,000 BP) and three snapshot HadCM3 simulations at 130,000 BP. Only with consideration of the possible feedback of West Antarctic Ice Sheet (WAIS) retreat does it become possible to simulate the magnitude of observed warming.
|Item Type:||Journal Article|
|Copyright Holders:||2010 The Authors|
|Project Funding Details:||
|Academic Unit/School:||Faculty of Science, Technology, Engineering and Mathematics (STEM) > Environment, Earth and Ecosystem Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
|Interdisciplinary Research Centre:||Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
International Development & Inclusive Innovation
|Depositing User:||Philip Holden|
|Date Deposited:||04 Aug 2010 11:08|
|Last Modified:||10 Feb 2017 10:57|
|Share this page:|
Download history for this item
These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.