Massive CO2 ice deposits sequestered in the south polar layered deposits of Mars

Roger J. Phillips; Brian J. Davis; Kenneth L. Tanaka; Shane Byrne; Michael T. Mellon; Nathaniel E. Putzig; Robert M. Haberle; Melinda A. Kahre; Bruce A. Campbell; Lynn M. Carter; Isaac B. Smith; John W. Holt; Suzanne E. Smrekar; Daniel C. Nunes; Jeffrey J. Plaut; Anthony F. Egan; Timothy N. Titus; Roberto Seu

doi:10.1126/science.1203091

USGS · 70004038

Massive CO2 ice deposits sequestered in the south polar layered deposits of Mars

Roger J. Phillips·Brian J. Davis·Kenneth L. Tanaka·Shane Byrne·Michael T. Mellon·Nathaniel E. Putzig·Robert M. Haberle·Melinda A. Kahre·Bruce A. Campbell·Lynn M. Carter·Isaac B. Smith·John W. Holt·Suzanne E. Smrekar·Daniel C. Nunes·Jeffrey J. Plaut·Anthony F. Egan·Timothy N. Titus·Roberto Seu

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Abstract

Shallow Radar soundings from the Mars Reconnaissance Orbiter reveal a buried deposit of carbon dioxide (CO 2 ) ice within the south polar layered deposits of Mars with a volume of 9500 to 12,500 cubic kilometers, about 30 times that previously estimated for the south pole residual cap. The deposit occurs within a stratigraphic unit that is uniquely marked by collapse features and other evidence of interior CO 2 volatile release. If released into the atmosphere at times of high obliquity, the CO 2 reservoir would increase the atmospheric mass by up to 80%, leading to more frequent and intense dust storms and to more regions where liquid water could persist without boiling.

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Roger J. Phillips, Brian J. Davis, Kenneth L. Tanaka, Shane Byrne, Michael T. Mellon, Nathaniel E. Putzig, Robert M. Haberle, Melinda A. Kahre, Bruce A. Campbell, Lynn M. Carter, Isaac B. Smith, John W. Holt, Suzanne E. Smrekar, Daniel C. Nunes, Jeffrey J. Plaut, Anthony F. Egan, Timothy N. Titus, Roberto Seu. 2011. Massive CO2 ice deposits sequestered in the south polar layered deposits of Mars. https://doi.org/10.1126/science.1203091

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