Under a landmark law passed in 2006, California is trying to cut its production of heat-trapping greenhouse gases that contribute to global warming. The state may create a carbon cap and trade system as a way to meet that goal.  But a coalition of environmental groups are against the pollution trading system. They say it won't bring emissions reductions.  KPBS Reporter Ed Joyce has more.

Here's a brief primer on cap and trade:  The cap is a limit on the pollution that's linked to global warming. Power plants, manufacturers, and others who release large amounts of carbon dioxide would have to meet those limits. The trade part creates a market with incentives for companies to reduce pollution, including trading credits for reducing emissions to other companies that exceed those limits.

But a broad-based coalition of environmental groups are against the carbon-trading plan to reduce the effects of climate change. They say the use of carbon trading will not achieve actual greenhouse gas emissions reductions. They also oppose Governor Schwarzenegger's proposal to develop a regional carbon cap and trade program.

Leo Miras of the Environmental Health Coalition in National City says it opens the door for companies to buy their way out of being regulated.

Miras: We're seeing through the Port of San Diego and the old South Bay Power Plant that we have down here, that businesses will resist change, even if the surrounding communities demand it. And the problem with cap-and-trade is it allows them not to change. And cap-and-trade does nothing to reduce our reliance on fossil fuels. It allows our communities to be subject to more and more pollution from power plants, both new and old.

He also says the cap and trade system creates an opportunity for what he called Enron style fraud.

Miras: And this is happening because the trading will occur in secret and we'll see reductions basically on paper only. And this is very disconcerting in both trying to get real emissions and in terms of business accountability issues.

Jane Williams of California Communities Against Toxics says alternatives such as energy efficiency policies, zero-carbon cars, and a carbon fee or tax would achieve actual reductions.

Williams: It's very clear to us that there is off the shelf technologies that are available right now to produce clean energy and to reduce pollution from cars. And it's not that those technologies are not viable, it's just that they're not politically viable.

She says the cap and trade system will allow companies to sit on the sidelines speculating about the future price of carbon instead of making the investments needed to change how energy is used and produced.

Williams citied a similar plan in Europe. She says that cap-and-trade system actually increased emissions, gave the worst polluters large profits and caused energy costs to increase for consumers.  Williams says the U.S. should learn from Europe's mistakes, not copy them.