| A coupled boundary layer---aeolian dust model of the Martian atmosphere is presented. This model was developed to determine how radiation scattering, absorption and emission by dust affects the boundary layer and, in turn, how this affects the dust distribution in the atmosphere. This was achieved by coupling a planetary boundary layer (PBL) model with a dynamical dust model. The model is applied to the 1977B dust storm optical data of Viking Lander 1 and our analysis indicates a significant improvement over previous 1D studies of dust storm decay.Thermocouples at three levels on a 1-m mast on the deck of the Phoenix lander provided temperature data throughout the 151 sol Phoenix mission. Air temperatures showed a large diurnal cycle which showed little sol to sol variation, especially over the first 90 sots of the mission. Daytime temperatures at the top (2 m) level typically rose to about 243 K (-30 C) in early afternoon and had large (10 K) turbulent fluctuations. These are analysed and used to estimate heat fluxes which are found to be in the range 2-10 W m-2 .By calibrating the model to observations of temperature and pressure from the Phoenix lander we have simulated the atmospheric ice formation observed by the Phoenix LIDAR and explored the potential influences of such formations on the atmospheric conditions. By simulating dust settling between multiple LIDAR observations we have estimated the effective radius of suspended dust, which is found to be in the range of estimates made by other methods. |
