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SUVs on Mars?
What's causing warming--on Mars?
Date published: 6/18/2007
(Rarely do we reprint editorials from other newspapers. However, we think the editorial below, published recently in the Providence (R.I.) Journal about global warming, is so well-argued and cooly reasoned that many of our readers would appreciate reading it. Please share your thoughts.--Editor)
THE PLANET is warming at an alarming rate--about half a degree Celsius since 1970. But, in this case, the planet under discussion is not Earth. It's Mars.
NASA scientists say the Red Planet is being hit by such rapid climate change that it could lose its southern ice cap. Could this mean that global warming is not entirely a manmade phenomenon? Certainly, it would be hard to blame Mars' warming on gas-guzzling SUVs and other fossil-fuel pollution, or methane released by cows that have proliferated to gratify meat-eaters.
Scientists theorize that Earth and Mars may be warming at roughly the same rate for radically different reasons. Researcher Lori Fenton, heading a team that compared maps of the Martian surface from the Viking mission of the 1970s with those made by the Mars Global Survey two decades later, speculates that temperature differences between light and dark portions of the planet may be stirring strong winds that are leading to further warming.
But others wonder whether solar activity may be driving much of the warming on both Earth and Mars.
At the same time, scientists at Lund University in Sweden maintain they have discovered that temperatures on Earth have historically risen and cooled in a seesaw pattern between the Northern and Southern hemispheres. In other words, they say, half of the globe seems to be warming while the other half is cooling. They based their study on core samples taken in various places around the globe and subjected to radiocarbon dating. As the scientists see it, the Northern Hemisphere's heating cycle may have peaked, and cooler temperatures may wait ahead.
These studies suggest that some skepticism may be in order toward those who assert that all the answers on global warming are in. As we have long argued, it does seem very clear from news accounts of scientific data that Earth has been warming, and that human activity has contributed to dramatically rising CO2 levels in the atmosphere, portending higher temperatures and associated problems in the decades ahead.
Read more stories about Fredericksburg
Date published: 6/18/2007
Most recent reader comments:
Further climate research needed
(posted by
BobG
, Sep. 25, 2007 2:41 pm)
I applaud the editorial on 6/18 concerning global warming. It appears to me that shortfalls in energy supply and distribution lie ahead. Coaxing an indifferent populace to save energy is going to be tricky. Perhaps the current enthusiasm for holding our climate constant will provide motivation. Funding basic research on climate will help insure that our efforts to conserve energy do no harm to climate and perhaps provide benefits to climate.
CO2 levels cycle naturally
(posted by
DeanFetterolf
, Sep. 25, 2007 2:41 pm)
The cycling (up&down) of CO2 levels over 6.5 ice ages (650,000 years) before present have been measured in air trapped in ice cores. See Science Nov 25, 2005 Vol 310 pages 1313-1316
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