Joel Aschbrenner

jaschbrenn@dmreg.com

James Hansen's pitch for reducing the greenhouse gases that cause climate change is boiled down to some basic numbers:

A fee of $10 per ton of carbon dioxide, increasing $10 each year, would reduce carbon dioxide emissions by 33 percent in a decade.

While such a carbon tax remains a third-rail issue politically, Hansen, an Iowa native and former director of NASA's Goddard Institute for Space Studies, says it's the best way to slow rising sea levels, superstorms and other catastrophes caused by climate change.

"In reality, we're headed down a path that is certain disaster if we stay on that path," he told Register editors and writers Wednesday.

Hansen said a carbon tax could be an economic development tool. Under the plan he advocates, every dollar raised would be distributed equally to legal U.S. residents. Hansen said it would raise the price of a gallon of gas by about $1, but would return about $2,000 annually to every resident.

He said the U.S. should lead on the issue. The first country to adopt a carbon tax will reap the benefits of owning new green technologies born out of incentives for reducing emissions, he said.

"It's a tragedy if we don't do it, because the solution is not that painful," he said.

Hansen is speaking on climate change this afternoon at the Heartland Global Health Consortium at Drake University and at 7 p.m. in the main lounge of the Iowa Memorial Union in Iowa City.

An early messenger, Hansen has been sounding alarm bells about the dangers of climate change since the 1980s, when he first testified before Congress. Today, he directs the climate science program at Columbia University's Earth Institute, where he is working on a paper called "Ice melt, sea level rise and superstorms."

Hansen said increasing temperatures will speed the melting of the planet's ice caps, raising sea levels and making coastal cities uninhabitable. But it's not just the coasts. Studies show a rise in global temperature of 3 degrees Celsius, which he said would happen by 2050 on the current trajectory, would reduce harvests in the U.S. corn belt by 46 percent, he said.

"We're already pushing beyond the safe level," he said. "We need to reduce carbon emissions as rapidly as is practical, and that's what putting an honest price on carbon will do."

What is practical, though, is a matter of debate. Opponents of a carbon tax say it would hamstring the economy, increasing the price of goods via higher fuel costs. Others say it would be fruitless for the United States to impose a carbon tax if the developing world continues to burn fossil fuels at an increasing rate.