Mars goes into meltdown
David Montgomery Science Correspondent
Science World 25/7/2001
IT MAY be a world away but soaring temperatures on Mars are giving scientists a speeded up
lesson on the effects of global warming.
A giant storm has wrapped the whole of Mars in a blanket of dust, causing the red planet
to heat up by about 30C in less than a month.
The climate change is due to too much of the sun’s energy being absorbed in the upper
atmosphere. Evidence of the meltdown has been beamed back to Earth by the Mars Global
Surveyor spacecraft orbiting the planet.
The craft also has sent back images showing that water was shaping Mars far more recently
than scientists previously supposed - ten million rather than four billion years ago.
Professor Victor Baker, head of the Department of Hydrology and Water Resources at the
University of Arizona in Tucson, said: "If it’s true, it would have major
implications for sending people to Mars, because it may mean that water is more available
than otherwise thought."
However, plans to send a manned mission to Mars may be hampered if the dust clouds plunge
the planet into a "nuclear winter".
Scientists said the storm started with a large dust storm in the southern latitudes late
last month, which grew until it enveloped almost the whole planet.
Professor Philip Christensen, one of a team investigating the data at Arizona State
University, said: "The dust trapped sunlight and heated the atmosphere locally. As
this warm air flowed to regions where the air was still cool, it generated winds which
raised more dust into the atmosphere.
"By the end of the first week in July, most of the planet was enveloped and our
readings of atmospheric temperature had increased by about 30C."
But Prof Christensen said the Martian heatwave was likely to bring a chill.
"In the end the cloaking of the entire planet with dust is probably going to cool
down the surface of Mars significantly... It’s kind of like what we imagine would
happen with a nuclear winter on Earth."
END OF
REPORT
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