Multi-step model of seasonal activity related to CO2 ice basal sublimation in Martian polar areas

Abstract

The model of processes involving basal sublimation of CO2 described in [4] has been further refined by introducing a more precise calculation of available solar energy depending on local topography (inclination effects) and neighboring terrain shadowing using ray-tracing. This model is now being adapted to describe northern circum-polar area activity. The application of our model to the northern polar areas (in addition to the southern) is justified by recent observations by Mars Reconnaissance Orbiter instruments (HiRISE and CRISM). Both polar regions have been repeatedly monitored during several spring seasons and the results of these observation campaigns lead to the conclusion that basal sublimation is active in both hemispheres.