Introduction

ALTHOUGH modern man has, in his history, experienced climates warmer than the present one (Lamb, 1982), he has no knowledge of the consequences of man's interference with the global climate. Simulation models, such as the General Circulation Model (GCM), are therefore useful tools, which provide us with an idea of the consequences of human tampering with the climate. The differences in the output of the models, as presented by Henderson-Sellers (Chapter 6), merely show that the present understanding of the mechanisms of climate does not match the need to foresee the future. One point to be learned from the models' output is that increasing the earth's atmospheric carbon-dioxide (CO2) content will increase the atmospheric temperature. They further show that the temperature increase will differ between latitudes, as well as between seasons.