Surface and boundary-layer modelling for the Mars Exploration Rover sites

✍ Scribed by Hannu Savijärvi; Janne Kauhanen

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 515 KB
• Volume: 134
• Category: Article
• ISSN: 0035-9009
• DOI: 10.1002/qj.232

✦ Synopsis

Abstract

The boundary layer and surface temperatures at the two Mars Exploration Rover sites (Spirit at Gusev Crater; Opportunity at Meridiani plains) were simulated with a soil–atmosphere column model and compared with the observations retrieved from scans through the thin and dusty CO~2~ atmosphere by the miniature thermal emission spectrometers (mini‐TES) onboard the two rovers.

The quite repetitive diurnal temperature cycle is reproduced fairly well by the model. In particular the surface temperatures appear to be well simulated. They are strongly controlled by the downwelling solar and thermal radiation from the atmosphere. Turbulent heat fluxes are small compared with net radiation, so they are relatively unimportant in the surface heat budget. Turbulence is nevertheless important in transferring heat convectively up from the radiatively heated and strongly superadiabatic daytime atmospheric surface layer. A strong surface inversion develops during each night.

The annual cycle is also well simulated, except that during the warm and dusty perihelion/summer period the temperatures appear overestimated by the model. This may be due to inaccurate handling of dust in the model, or to dust accumulation on the instrument optics, or perhaps both. The annual temperature cycle demonstrates the large eccentricity of Mars' orbit, the seasonal effects and the variable dustiness of the atmosphere. Copyright © 2008 Royal Meteorological Society