The Role of Climate Sensitivity and Ocean Heat Uptake on AOGCM Transient Temperature Response

The role of climate sensitivity and ocean heat uptake in determining the range of climate model response is investigated in the CMIP2 AOGCM results. The fraction of equilibrium warming that is realised at any one time is less in those models with higher climate sensitivity, leading to a reduction in the temperature response range at the time of CO2 doubling (TCR range transient climate response). The range is reduced by a farther 15% due to an apparent relationship between climate sensitivity and the efficiency of ocean heat uptake. Some possible physical causes for this relationship are suggested.