Winter clouds over the North Martian Polar Cap

  title={Winter clouds over the North Martian Polar Cap},
  author={Gordon H. Pettengill and Peter G. Ford},
  journal={Geophysical Research Letters},
The Mars Orbiter Laser Altimeter (MOLA) experiment, carried on the Mars Global Surveyor spacecraft, has observed echoes from cloud tops on roughly 2.5% of the total data taken above 70°N over the northern winter Martian polar hood from March to June 1998. Sloping wavefronts are commonly seen at latitudes above 70°N, implying the presence of propagating buoyancy waves. Since these wavefronts frequently extend from the surface up to 10 km at a time when CO2 is known to be condensing on the polar… Expand

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