A Sublimation Model for Martian South Polar Ice Features
Shane Byrne,*
Andrew P. Ingersoll
In their pioneering work, Leighton and Murray argued that the Mars
atmosphere, which at present is 95% carbon dioxide, is controlled by
vapor equilibrium with a much larger polar reservoir of solid carbon
dioxide. Here we argue that the polar reservoir is small and cannot
function as a long-term buffer to the more massive atmosphere. Our work
is based on modeling of the circular depressions commonly found on the
south polar cap. We argue that a carbon dioxide ice layer about 8 meters thick is being etched away to reveal water ice underneath. This
is consistent with thermal infrared data from the Mars Odyssey mission.
Division of Geological and Planetary Sciences, California
Institute of Technology, 1200 East California Boulevard, Pasadena, CA
91125, USA.
*
To whom correspondence should be addressed. E-mail:
shane{at}gps.caltech.edu
