Seasonal and Latitudinal Variations of the Average Surface Temperature and Vertical Temperature Profile on Mars

Abstract

The seasonal and latitudinal variations of the average surface temperature and vertical profile of atmospheric temperature on Mars are computed using a thermal equilibrium model. It is assumed that carbon dioxide is the sole radiating gas in a model atmosphere that is composed of 60% carbon dioxide and has a surface pressure of 10 mb. The results are presented in the form of pole-to-pole temperature cross sections from the surface to about 40 km for each Martian season. The computed temperature cross sections indicate: 1) extremely small latitudinal temperature gradients in the summer hemisphere, with the maximum temperature occurring at the pole; 2) a decrease of tropopause altitude with latitude from a maximum at the equator during the equinoctial seasons and at the summer pole during the solstices; and 3) relatively isothermal vertical structure at high latitudes during the equinoxes and winter. Comparisons, where possible, of the present results with other theoretical studies and with the microwave observational indications of Martian temperatures yield generally good agreement.