By Frederic J. Frommer

Sen. Amy Klobuchar, who made the environment a key issue in her Senate campaign last year, proposed a national registry of greenhouse gas emissions Monday as part of an attempt to help reduce such emissions.

Klobuchar's legislation, which she dubbed a "carbon counter," would help track greenhouse gases as a prelude to legislative efforts to limit emissions through a cap-and-trade or other approach. A cap-and-trade system sets limits on carbon emissions and makes companies pay for producing greenhouse gases.

"If you don't know what you are looking at and can't measure it, you can't fix it," said Klobuchar, D-Minn. "If weight watchers can have a calorie counter, we should be able to put in place a national 'carbon counter' so we can figure out the best way to reduce emissions that is good for businesses and good for the environment."

Klobuchar introduced the bill with Sen. Olympia Snowe, R-Maine.

"If we are going to make a mandatory cap-and-trade system work — which is the most effective way of reducing greenhouse gases — we need the best data available on greenhouse gas emissions in the United States," Snowe said.

The bill would require facilities to report their greenhouse gas emissions to the Environmental Protection Agency.