Climatic modeling of the earth-atmosphere system

During the course of this research three global climate models (I, II, and III) have been developed. The first two are vertically-integrated and use a grid spacing of 10 deg of latitude in the north-south direction. Model I differentiates zonally only between land and water. Model II uses a zonal grid of 10 deg of longitude and is the only one of the models to include a hydrologic cycle and variable cloud cover. Model III is a two-dimensional zonally-averaged model with a grid spacing of 7.5 deg of latitude horizontally and 3 km vertically (10 layers). Each model has its own advantages and disadvantages. Model I is probably the most practical to use in studies of climatic change. The model is fast, requiring very little computer time, and reproduces the present climate of the earth quite well. Models II and III should both be improved considerably before being used in studies of climatic change.