Extra-terrestrial warming

An editorial
The Providence Journal
Tuesday, June 12, 2007

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. That being the case, we should move to reduce our dependence on fossil fuels, including through wind power -- not only for the sake of the environment, but also to stop stuffing so much money into the pockets of corrupt and terror-supporting regimes.

But it is important to remember that climate science is complex, that Earth has repeatedly gone through cycles of warming and cooling, and that our computer models are not yet able to accurately predict climate long-term. Some scientists, citing sunspot activity, argue that rising CO2 levels in the atmosphere are the result more than the cause of warming, and that only 4 percent of CO2 is caused by humans, the rest by nature. It's not entirely clear how much we can reduce CO2, even if we muster the political will to make sharp reductions in pollution.

Rigorous, fearless and skeptical scientific exploration is needed as we try to sort out what is going on. Meanwhile, we ought to develop alternative energy sources to fossil fuel, and quickly.