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Mars pathfinder: New data and new model simulations
Author(s) -
Savijärvi Hannu,
Määttänen Anni,
Kauhanen Janne,
Harri Arimatti
Publication year - 2004
Publication title -
quarterly journal of the royal meteorological society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.744
H-Index - 143
eISSN - 1477-870X
pISSN - 0035-9009
DOI - 10.1256/qj.03.59
Subject(s) - mars exploration program , atmospheric sciences , environmental science , atmosphere of mars , diurnal cycle , daytime , sunrise , meteorology , thermal , martian , atmosphere (unit) , physics , astrobiology
The diurnal cycle in the temperature and wind speed of the Mars Pathfinder lander (MPF) is compared with the results from a one‐dimensional high‐solution boundary‐layer model. The radiation scheme of the model has been validated against line‐by‐line calculations in an average Martian case. The agreement with MPF observations is good. Strong daytime turbulent variability and steep vertical temperature gradients characterize the observations. A detailed look at the model physics reveals that the thin atmosphere responds strongly to thermal radiation. During the daytime, absorption of surface‐emitted thermal radiation by CO 2 , water vapour and dust is the main heating agent below 200 m despite the fact that the surface layer is strongly convective and dust absorbs solar radiation. The night‐time inversion is also transferred to the air mainly by long‐wave processes, although turbulent cooling dominates very near the surface (below 40 m). The near‐surface net heating/cooling displays a sensitive balance between several large and opposite physical processes, wherefore accurate algorithms and high resolution are needed for detailed model results. The modelled hydrologic cycle reveals a well‐mixed layer of up to 5 km with thin icy fog and frost forming in the night‐time. These sublimate back to the air soon after sunrise. Copyright © 2004 Royal Meteorological Society