'U' researchers turn attention to global warming

While global warming continues to capture the spotlight as a hot international topic, University researchers are quietly forming their own theories on global warming's environmental effects, and problems that will be encountered as nations try to combat its damaging consequences.

The basic cause of global warming is the increase of carbon dioxide (CO2) in the earth's atmosphere, said University biologist James Teeri.

"CO2 is rising in the atmosphere at an unprecedented rate," Teeri said. "It has gone up 30 percent since the start of the Industrial Revolution."

This increase of CO2 and other artificial gases in the atmosphere has been accompanied by a worldwide increase in temperature, Teeri said.

"It is clear that the temperature has risen over the last century, and it is likely that CO2 and other manmade gases have contributed," he said.

Teeri and other University researchers have discovered an unexpected result of the increased levels of CO2 in the atmosphere, - one that could have serious effects: "Elevated CO2 changes how green plants grow," Teeri said.

Teeri's research has shown that green plants grown in high levels of CO2 are larger but have much less nutritional value in their leaves. Herbivores that eat these energy-deficient plants - as well as the predators that eat these herbivores - grow smaller, producing a chain reaction throughout the entire global ecosystem. The full impact of this discovery is not yet clear.

The simple solution to global warming and other related issues is to reduce carbon emissions, but this is easier said than done. In order to reduce carbon emissions, nations have to stop burning conventional fossil fuels, and increase the usage of cleaner alternative fuel sources.

"The major difficulty is that trying to cut greenhouse gas emissions involves dealing with all the things that are central to our growth," said political science Prof. Harold Jacobson.

Jacobson said all sources of greenhouse gases, including cars, factories and many others, must be altered in order to reduce emissions.

"We have to change all of those," Jacobson said. "It goes to the heart of (our society)."

But the switch from fossil fuels to alternative fuel sources is fraught with uncertainties.

Nations planning to cut carbon emissions by reducing the amount of fossil fuels they burn have to account for several unknowns. For instance, no one knows the exact number of world fossil fuel reserves, and how long they will last. Also, the world cannot depend on cleaner alternative fuel sources that do not yet exist, such as nuclear fusion and fuel cell technology.

To make matters worse, many nations planning to cut carbon emissions are not taking these uncertainities into account.

In an effort to account for all possible situations, Industrial and Operations Engineering Prof. John Birge has developed a model for the economic effects of reducing carbon emmissions.

Birge's model incorporates the uncertainties involved in switching from conventional to alternative energy resources, such as the remaining amount of global fossil fuel reserves, and the rate of development of fusion and fuel cells.

"We can't base policy on best guesses," Birge said. "The effect of plugging in your best guess can be almost catastrophic."

Birge calculated that in the United States, the cost of ignoring the uncertainty involved in reducing carbon emissions would be about two percent of the U.S. economy, or billions of dollars.

"Our policy has to be pretty broad," Birge said. "We can't invest in any one thing."

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