MODELLING CLIMATE CHANGE OVER THE LAST 21,000 YEARS

Computer climate models have been extensively used to investigate a number of periods during the last glacial-interglacial cycle. In particular, many previous studies have focussed on model simulations of the atmosphere or ocean only. A new generation of climate models couples these together with terrestrial (and oceanic) changes to the carbon cycle, and to atmospheric chemistry. We will review the results from these models and present new results focussing on the termination of the last glacial. The model highlights the importance of the ocean for the Bolling-Allerod warm event. In addition, the role of vegetation-climate feedbacks will be discussed. The Asian monsoon shows relatively little sensitivity to changes in vegetation whereas the North African monsoon shows a big effect in the Holocene, but small effects during glacial periods.