title: CO2 snow depth and subsurface water-ice abundance in the northern hemisphere of Mars.
abstract: Observations of seasonal variations of neutron flux from the high-energy neutron detector (HEND) on Mars Odyssey combined with direct measurements of the thickness of condensed carbon dioxide by the Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor show a latitudinal dependence of northern winter deposition of carbon dioxide. The observations are also consistent with a shallow substrate consisting of a layer with water ice overlain by a layer of drier soil. The lower ice-rich layer contains between 50 and 75 weight % water, indicating that the shallow subsurface at northern polar latitudes on Mars is even more water rich than that in the south.
authors.affiliation: Space Research Institute, Russian Academy of Sciences, Moscow, 117997, Russia. imitrofa@space.ru
authors.forename: I G
authors.initials: IG
authors.lastname: Mitrofanov
authors.forename: M T
authors.initials: MT
authors.lastname: Zuber
authors.forename: M L
authors.initials: ML
authors.lastname: Litvak
authors.forename: W V
authors.initials: WV
authors.lastname: Boynton
authors.forename: D E
authors.initials: DE
authors.lastname: Smith
authors.forename: D
authors.initials: D
authors.lastname: Drake
authors.forename: D
authors.initials: D
authors.lastname: Hamara
authors.forename: A S
authors.initials: AS
authors.lastname: Kozyrev
authors.forename: A B
authors.initials: AB
authors.lastname: Sanin
authors.forename: C
authors.initials: C
authors.lastname: Shinohara
authors.forename: R S
authors.initials: RS
authors.lastname: Saunders
authors.forename: V
authors.initials: V
authors.lastname: Tretyakov
mesh_terms: D001272:Atmosphere; D004367:Dry Ice; D005118:Extraterrestrial Environment; D018535:Mars; D012621:Seasons; D014867:Water / Q000032:analysis*
chemical_list: D004367:Dry Ice; D014867:Water