There were nights not too long ago when it may have been hard to believe that the Earth is getting warmer -- nights when the wind-chill factor reached 50 below zero and icicles five feet long formed under rain gutters.

But the reality is that average yearly temperatures around the globe are increasing -- and some University researchers are making it their problem.

"I don't believe conservation is going to stop this from happening," said Eric Barron, professor of geosciences and director of the University's Earth System Science Center, which is dedicated to the study of global change.

Although present data point to a warming trend, predicting the climate's future is hard to do, Barron said.

"There's no way we can incorporate what every molecule on the planet does," he added.

The present method of forecasting global climate changes is based on models of what the planet could look like in the future, which are calculated by computer. These show how variables, such as the increasing levels of carbon dioxide and methane in the atmosphere, will affect the Earth.

These gases, commonly known as greenhouse gases, are trapping heat inside the Earth's atmosphere. The gases collect in the atmosphere and reflect the sun's radiation that has already bounced off the Earth's surface back onto the planet.

The science center uses a computer that can complete 666 million calculations per second to estimate what changes the planet may go through in the next few decades.

"We have to ultimately figure out alternative fuels for fossil fuels," said Jim Kasting, professor of geosciences. Kasting's research found that even when burning fossil fuels -- in forms such as coal and wood -- decreases by 50 percent, the effects of the climate change will only be slightly delayed, not stopped.

The outlook may be dim, but an element of uncertainty exists in all the predictions.

"Assigning a cause to these temperature changes in such a complex system is not easy to do," said Alistair Fraser, a professor of meteorology who teaches students in his introductory meteorology course about global changes and the greenhouse effect.

Fraser said the trend toward higher temperatures is a concern, but because natural cycles in the planet's climate are hard to understand, he advises all his students to treat studies with a certain amount of skepticism, even if they've been done by experts.

"I end up cautioning them about what they may read," he said.

Janice Snyder, a member of Eco-Action, said she is encouraged by the University's research but understands Fraser's reservations.

"From what I've read, there are studies which can prove almost anything," she said. "I personally do think it's a problem."

Brent Yarnal, associate geography professor and also an associate of the Earth System Science Center, studies the social effects of climatic changes. His studies in Bulgaria are helping him learn how radical changes in society are affecting things like energy usage.

"On almost every measure, they were the most inefficient energy user in the entire former Soviet bloc," he said.

Ian Bowles, who is assisting Yarnal in his research, will be traveling to Bulgaria this summer to observe changes in how Bulgarians use energy. Bulgarian citizens can fend off energy problems Americans have faced by carefully restructuring their government, said Bowles (graduate-geography).

"They can avoid a lot of the problems that we have had to work through," he said.