Late Pleistocene Ice Age Scenarios Based on Observational Evidence

Open Access
Publisher Website
Google Scholar
Abstract
Ice age scenarios for the last glacial-interglacial cycle, based on observations of Boyle and Keigwin concerning the North Atlantic thermohaline circulation and of Barnola et al. concerning atmospheric C02 variations derived from the Vostok ice cores, are herein analyzed. Northern Hemisphere continental ice sheets are simulated with an energy balance model (EBM) that is asynchronously coupled to vertically integrated ice sheet models based on the Glen flow law. The EBM includes both a realistic land-sea distribution and temperature-albedo feedback and is driven with orbital variations of effective solar insulation. With the addition of atmospheric C02 and ocean heat flux variations, but not in their absence, a complete collapse is obtained for the Eurasian ice sheet but not for the North American ice sheet. We therefore suggest that further feedback mechanisms, perhaps involving more accurate modeling of the dynamics of the mostly marine-based Laurentide complex appears necessary to explain termi... Abstract Ice age scenarios for the last glacial-interglacial cycle, based on observations of Boyle and Keigwin concerning the North Atlantic thermohaline circulation and of Barnola et al. concerning atmospheric C02 variations derived from the Vostok ice cores, are herein analyzed. Northern Hemisphere continental ice sheets are simulated with an energy balance model (EBM) that is asynchronously coupled to vertically integrated ice sheet models based on the Glen flow law. The EBM includes both a realistic land-sea distribution and temperature-albedo feedback and is driven with orbital variations of effective solar insulation. With the addition of atmospheric C02 and ocean heat flux variations, but not in their absence, a complete collapse is obtained for the Eurasian ice sheet but not for the North American ice sheet. We therefore suggest that further feedback mechanisms, perhaps involving more accurate modeling of the dynamics of the mostly marine-based Laurentide complex appears necessary to explain termi...

This publication has 0 references indexed in Scilit: