Mar 19 - McClatchy-Tribune Regional News - Cosby Woodruff Montgomery Advertiser, Ala.

The Earth is getting warmer, but Alabama's state climatologist says carbon fuels aren't to blame.

John Christy, who heads the Earth System Science Center at the University of Alabama- Huntsville, told a group of civic and business leaders Tuesday that the Earth's warming is well within historical ranges.

He spoke at the Energy and Environment Lecture sponsored by Auburn Montgomery and Alabama Power Co.

Carbon dioxide levels have increased 38 percent in the last 100 years, Christy said, leading to an increase in the average surface temperature of about 1.26 degrees. Even if carbon dioxide doubled, temperatures would increase only about 3.6 degrees, according to Christy.

"The climate is always in change," he said. "Glaciers are always advancing or retreating.

"Think of it this way, would you rather the glaciers be advancing?"

Energy use, specifically carbon-based fuels such as coal, is responsible for some temperature increases, Christy said. But the societal benefits of energy far outweigh the pollution, he added.

Life expectancy has soared over the last 100 years, he said, largely because of more efficient energy uses. That makes solutions that call for an end to carbon-based fuels unrealistic.

"There is no substitute for the carbon fuels we have now," said Christy.

Wind and solar power work on a limited scale, he said, but they impact the environment as well.

Christy said those who claim global warming spells doom for society fall into three categories.

True believers, he said, claim that any impact humans have on Earth is negative. Others are looking to make a profit. The third group just has a bleak feeling about the environment and wants to do something.

The last group can be a positive force, he said, if they make changes based on what he called sound science.

"Everyone should look at their energy uses and find ways to save money," he said. "If you are saving money, you are probably saving energy."

The government can help by encouraging new fuels.

"Making energy more expensive is a regressive tax," he said.