36. INTERGLACIALS AS SIMULATED BY THE LLN 2-D NH AND MOBIDIC CLIMATE MODELS

Abstract

Two Earth system models of intermediate complexity (EMICs), i.e. LLN 2-D NH and MoBidiC, were designed in Louvain-la-Neuve to test the astronomical theory of palaeoclimate. The purpose was to see whether the astronomically driven insolation is the main driver of climate change over the last glacial-interglacial cycles. It also aims at identifying the major processes and feedbacks at work in the climate system. Here, we report on the results obtained for the interglacial periods of the last 800 kyr and for the future over the next 100 kyr. Major processes governing the response of the modelled climate system to insolation and/or CO2 changes are related to the albedo-temperature and water vapourtemperature feedbacks, to the taiga-tundra direct and indirect impacts on highlatitudes surface albedo, to the altitude and continental effects on the precipitation over the ice sheets, to the lagging lithospheric response to the ice-sheet loading and to the mechanical destabilisation of the ice sheets through the rapid melting of their southern front as compared to the northern. © 2007 Elsevier B.V. All rights reserved.