Volcanic forcing and climate variations during the last glacial period
A. F. Flinders
1University of Rhode Island, Graduate School of Oceanography, USA 2University of New Hampshire, Center for Coastal and Ocean Mapping, USA
Received: 08 Aug 2012 – Accepted for review: 03 Sep 2012 – Discussion started: 05 Oct 2012
Abstract. Measurements of δ18O in the Greenland Ice Sheet Project 2 (GISP2) ice-core from Summit, Greenland, show repeated temporal variations associated with rapid warming events throughout the last glacial period of the Pleistocene-10–110 kya. The majority of these warming events are preceded in the ice-core record by an increased concentration of insoluble micro-particulate sulfate, indicative of increases in global volcanism. Wavelet analysis of ice-core and marine-sediment records show a repeated 5000–6000 yr periodicity in both volcanic SO4 and δ18O ice records, as well as a 5000–8000 yr cycle in the lithic concentration of ice-rafted debris, atmospheric CO2 concentration, and a database of late Quaternary volcanic eruptions. Increasing concentrations in atmospheric CO2 and CH4 initiated during periods of increased volcanism, peaking during a warm transition, reflect a volcanic-atmospheric-deglaciation feedback, regulated by meridional overturning current-shutdown related cooling.
Flinders, A. F.: Volcanic forcing and climate variations during the last glacial period, Clim. Past Discuss., 8, 4941-4956, doi:10.5194/cpd-8-4941-2012, 2012.