SACRAMENTO – Gov. Arnold Schwarzenegger has signed legislation that attempts to limit greenhouse gases by curbing urban sprawl.

The bill by Sen. Darrell Steinberg, a Sacramento Democrat, creates incentives for local governments to rein in sprawl by funding transportation projects that are designed to reduce commutes.

Supporters say the bill is needed to help implement the landmark global warming bill Schwarzenegger signed in 2006. That measure requires the state to reduce its greenhouse gas emissions to 1990 levels by 2020.

The governor signed the Steinberg bill on Tuesday. It requires the California Air Resources Board to set targets for reducing auto emissions for 17 regional planning agencies.

Cities and counties would not be required to implement those goals when they plan for new development but could lose transportation funding if they don't.