immortalachilles writes "Gale crater is at 5.4S 137.8E on Mars. Unlike Earth, no "wet"/"dry" seasons at equator more like higher/lower pressure. "The seasonal increase (in pressure) results from tons of carbon dioxide, which had been frozen into a southern (or northern) winter ice cap, returning into the atmosphere as southern (or northern) spring turns to summer. The daily cycle of higher pressure in the morning and lower pressure in the evening results from daytime heating of the atmosphere by the sun. As morning works its way westward around the planet, so does a wave of heat-expanded atmosphere, known as a thermal tide." "30% of atmosphere condensing out twice a year." — REMS scientist Claire Newman. On the radiation front, "it depends on the particle". "Total dose anti-correlated with pressure". However, "neutrons and "secondary particles" seem to increase with atmospheric pressure", products of high-energy collisions with molecules in the atmosphere. — Dr. Don Hassler. Radiation numbers in interpretable units said to be released at the AGU (American Geophysical Union) Meeting, 3-7 December in San Francisco. http://www.ustream.tv/recorded/27047602"
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