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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 112,
E08005,
doi:10.1029/2006JE002816,
2007
Cold jets in the Martian polar caps
Hugh H. Kieffer
Celestial Reasonings, Genoa, Nevada, USA
Abstract
Mars seasonal polar caps display dark ice, local darker spots, aligned elongate patches, and radially dendritic forms that
reverse albedo contrast. The unexpected variety and sequence of these features are explained on the basis of processes involving
CO2, dust, sand, and H2O. These processes are largely related to the atmosphere being near its saturation temperature, and they have few terrestrial
analogies. In the simplest case the ∼1 m thick seasonal cap, initially dusty, cleans itself and becomes translucent after
sunrise and is impermeable over extensive regions except for local vents. The slab ice sublimates at the base and is levitated
on high-pressure gas, causing humidity exchange with deeper layers; subslab gas converging toward the vents erodes channels
in the soil and ejects this material in high-velocity jets. Recent spectral observations indicate great variety in the details.
Received 20
August
2006;
accepted 29
June
2007;
published 9
August
2007.
Keywords: Mars;
ice;
vents.
Index Terms: 5462 Planetary Sciences: Solid Surface Planets: Polar regions; 5464 Planetary Sciences: Solid Surface Planets: Remote sensing; 5422 Planetary Sciences: Solid Surface Planets: Ices; 5445 Planetary Sciences: Solid Surface Planets: Meteorology (3346); 5460 Planetary Sciences: Solid Surface Planets: Physical properties of materials.
Read Full Article (file size: 502865 bytes) Cited by
Citation: Kieffer, H. H.
(2007),
Cold jets in the Martian polar caps,
J. Geophys. Res.,
112,
E08005,
doi:10.1029/2006JE002816.
Copyright 2007 by the American Geophysical Union.
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