A Simple Subgrid-Scale Model for Slope Winds on Mars

Global Climate Models (GCMs) are useful tools for simulating the dynamics of Mars atmosphere on a planetary scale. However their coarse resolution ((Formula presented.) 100 km) does not allow to capture small-scale phenomena such as slope winds which can occur over scales of just a few kilometers. These local slope winds can be crucial in Mars climate modeling, since they can significantly contribute to dust lifting affecting the amount of dust in the atmosphere, which is the major factor that governs the variability in Mars atmosphere. These winds can also affect the sublimation of water and (Formula presented.) ice on the surface, both playing a key role in the Martian climate. In this study, we aim to develop a simple and efficient numerical model to simulate slope winds on Mars in single column and global climate models. We compare the model results with those from a mesoscale model with a resolution of a few kilometers capable of resolving these small scale winds (but only for a few days and with a high computational cost). This simple model of slope winds has been included in the Mars Climate Database (MCD v6.1) tool.