The effect of land-sea temperature contrast on short-term numerical forecasts

A simple scheme for the calculation of land surface temperature by means of the solution of the heat balance equation is outlined. Features include diurnal variation of solar insolation and a stability dependent drag coefficient. Experiments are described in which the scheme is used to gauge the relevance of land-sea surface temperature contrasts to short-term numerical predictions in the Australian region. In the experiments land surface temperature is specified using the scheme while sea surface temperatures are set to climatological values. Prognoses for three summer situations are compared with prognoses performed with the scheme omitted. In each case the prognosis performed by the model including the surface heat balance gives improvements in the mean sea level pressure pattern which would be of direct consequence for weather forecasts in the southern Australian States.