Colman, R. A., B. J. McAvaney, and R. T. Wetherald, 1994. Sensitivity of the Australian surface hydrology and energy budgets to a doubling of CO₂. Australian Meteorological Magazine, 43, 105-116.

Abstract: Changes in surface temperature, hydrology and energy budgets are examined over Australia for an equlibrium doubled CO₂ experiment using the Bureau of Meteorology Research Centre (BMRC) general circulation model (GCM). Changes in the surface hydrology budget are compared with those modelled using the Geophysical Fluid Dynamics Laboratory GCM. The continent is divided into northern and southern regions. These regions display soil moisture maxima in summer and winter respectively in both models, which essentially reflects the simulated seasonality of precipitation and evaporation. In the modelled doubled CO₂ climate, the BMRC GCM finds a strong increase in soil moisture in northern Australia in summer, due to a large increase in precipitation. Both models find a decrease in soil moisture in southern Australia in winter. This may be contrasted with a summer drying generally found at mid-latitudes in the northern hemisphere by GCMs. The BMRC model shows the crucial change in southern Australia to be a decrease in autumn precipitation. The findings highlight the danger of considering precipitation changes alone when assessing climate change impacts, as large increases in precipitation throughout most of the year do not result in increases in soil moisture. The soil moisture/cloud feedback mechanism proposed for northern continents appears to operate in Australia as well, although does not extend to high-level clouds. Changes in the surface heat budget involve a general increase in downwards long wave radiation except for southern Australia in autumn. The model response generally produces a close `pairing' of long and short wave radiation changes, caused primarily by clouds and resulting in net radiative changes at the surface close to zero. This forces a similar pairing of latent and sensible heat changes to occur also.