We describe a simplified physics approach to generating time-varying global wind and temperature fields suitable for conducting transport studies on Mars. The goal is to develop a computationally fast algorithm that will enable long-term simulations of the planet's climate system. Thus we use a three-dimensional log-pressure global spectral model forced with a simplified physics package based on Newtonian cooling and Rayleigh friction. We examine the model's performance at northern winter solstice for clear and dusty conditions and find that the simulated mean meridional circulation and transient eddies compare well with a more sophisticated general circulation model by tuning a single parameter: the thermal damping time. Best results are obtained for a thermal damping time of 2 days for clear conditions and 1 day for dusty conditions.¿ 1997 American Geophysical Union