Many U.S. states have joined regional compacts to reduce emissions and greenhouse gases. Some states have also taken measures independently and through lawsuits.  Among the regional and local actions:   Several Northeast states agreed in 2005 to curb carbon dioxide emissions from power plants by 10% by 2019 as part of the Regional Greenhouse Gas Initiative. Connecticut, Delaware, Maine, New Hampshire, New Jersey, New York and Vermont are among the participating states.   Six Western states and two Canadian provinces agreed this year to a regional goal of reducing emissions by 15% over 2005 levels within 13 years, partly by designing a market-based system such as a cap-and-trade program planned by California. The Western Climate Initiative includes Arizona, California, New Mexico, Oregon, Utah and Washington and the provinces of British Columbia and Manitoba.   Several Midwestern states and Manitoba signed an agreement to reduce energy consumption, focus more on renewable energy and limit greenhouse gas emissions. The plan calls for a reduction in carbon emissions of between 60% and 80%. Wisconsin, Minnesota, Iowa, South Dakota and Michigan have signed the agreement, and four other states were expected to join them.   California last year adopted a sweeping law requiring reductions of about 25% in greenhouse gases by 2020.   California also sued the federal government last month to force a decision about whether the state can impose the nation's first greenhouse gas emission standards for cars and light trucks. More than a dozen other states have vowed to adopt the standards.   More than 700 U.S. mayors have signed onto an agreement to meet or beat the Kyoto Protocol targets by 2012; that would mean reducing emissions by 7% from 1990 levels.   A new law in Maine requires the state's six largest power plants to pay for the right to release carbon dioxide, the heat-trapping gas most blamed for global warming.   New Jersey enacted a law this summer that requires the state to reduce global warming gases to 1990 levels by 2020, and to reduce greenhouse gas emissions to 80% below 2006 levels by 2050.   Florida Gov. Charlie Crist signed orders this summer that will require state agencies to conserve energy and power companies to use more renewable energy.   Seattle claims city operations have cut greenhouse-gas emissions by 60% through motor pools of hybrid cars, trucks using biodiesel fuel and other measures.   New York Mayor Michael Bloomberg wants to reduce his city's emissions by 30% by 2030, by requiring taxis to switch to gas-saving hybrid vehicles, for example, and most controversially by proposing fees for vehicles to enter lower Manhattan.
Handing a major defeat to the auto industry, a federal judge ruled Wednesday that California can regulate greenhouse gas emissions from vehicles.