Governor Mitt Romney plans to unveil a comprehensive agenda on climate change today, which officials said would make Massachusetts the first state to consider the impact on greenhouse gases when state regulators evaluate highway projects and other public construction plans.
Massachusetts, which was the first state to regulate carbon dioxide emissions from power plants, would go further by basing its transportation planning and funding decisions in part on the greenhouse gases that projects would produce. The plan also suggests giving the owners of hybrid cars tax breaks and the right to use high-occupancy vehicle lanes even without passengers.
The Massachusetts Climate Protection Plan represents the state's effort to meet regional emissions goals that New England's governors and Eastern Canada's premiers embraced in 2001.
The plan was cheered by environmental groups, which had hoped for a strong signal that Romney would extend the previous administration's efforts to limit greenhouse gases.
"Governor Romney is making it clear that he understands that failure to act on climate change is not an option," said Frank Gorke, of the Massachusetts Public Interest Research Group. "And that he understands that, to rise to the challenge of reducing pollution, states have to lead by example."
The plan features roughly 70 policy initiatives -- including proposed laws, incentive programs, and regulatory changes -- some of which are in the works. Since the plan does not estimate how much its measures will reduce emissions, it is unclear whether it will meet its stated goals of reducing greenhouse gases to 1990 levels by 2010 and by what amounts to a further 10 percent by 2020.
The administration did not provide an estimate of how much the plan would cost.
The final plan backed off one key provision of an earlier draft obtained by the Globe: a commitment to reduce greenhouse gases by 75 percent to 85 percent by the year 2050. That deadline would have made Massachusetts the first state to set a date for achieving the reductions many climate specialists say are needed to slow global warming.
The administration had planned to release the report at an Earth Day event on April 24, but delayed the report for nearly two weeks for review by the governor, state agencies, and business and environmental groups. The final plan calls for the same long-term reductions, but does not set a target date.
That change drew fire from some environmentalists.
"Timing does matter," said Kevin Knobloch, president and chief executive of the Union of Concerned Scientists, a national scientists' group concerned with environmental issues. "Greenhouse gas emissions stay in the atmosphere for over 100 years and our ability to avoid those worst impacts for our children in their lifetimes is dependent on our aggressively reducing emissions in the first half of this century."
Those who drafted the plan say they dropped the date because there was no scientific basis for setting it at 2050 and because future innovations will be necessary to achieve such reductions.
"It was a consensus view that unless we could prove how we were going to achieve it, which was the whole point of the plan, that we should get on with the near- and midterm goals," said Douglas Foy, the head of Romney's Office of Commonwealth Development.
While the Massachusetts plan calls for one significant mandatory imposition on business, requiring large industries to report their carbon dioxide emissions, most of its features are voluntary or imposed on the state and other public entities. Nationally, about one-third of carbon dioxide emissions come from cars and other transportation sources. Despite tougher auto standards, emissions are increasing because of the prevalence of less fuel-efficient sport utility vehicles and an increase in the miles people are driving. The plan also calls for the state to curb sprawl and thus reduce motorists' time on the road, through better planning, and to promote higher mixed-use development at transit stations.
"This is really a plan that we will execute," Foy said. "It's not just a declaration. It's a promise."
With limited industry in Massachusetts, the state is not a major source of greenhouse gases on the national scale, contributing less than 2 percent of the country's carbon dioxide emissions. But the state's share is similar to that of the entire countries of Portugal, Austria, or Greece, the climate plan says.
"The impact of efforts to reduce greenhouse gases here in Massachusetts should not be underestimated," the plan says. "Nor should the example our state actions can set for other political jurisdictions."
Massachusetts and other Northeastern states are also developing a regional cap for carbon dioxide emissions and a system that would allow emitters to trade credits, similar to a plan that helped reduce emissions that produce acid rain.
Some activists pointed out that the plan is part of a long tradition of states setting tougher environmental rules than the federal government. California, for instance, has long been the leader in adopting stricter auto emissions standards.
Advocates yesterday said they were encouraged to see the Republican governor move forward on climate change issues that the White House has not addressed.
"It's a high-profile Republican saying this problem isn't a . . . scientific quandary. It's a real problem and one that needs to be acted on," said Kenneth Colburn, executive director of the Northeast States for Coordinated Air Use Management, which handles technical issues on air-quality policy.
The Union of Concerned Scientists has accused the Bush administration of injecting too much uncertainty into the scientific consensus on global warming. In June, The New York Times reported that the White House had edited a report on the state of the environment so heavily that the US Environmental Protection Agency ended up deleting references to global warming, rather than present information that agency scientists said was incomplete. Among the omissions was a 2001 review by the National Academy of Sciences, commissioned by the White House, concluding that human activity is significantly contributing to warming.
The Romney plan points to that scientific consensus and to predictions by the International Panel for Climate Change, which represents more than 2,000 leading climate scientists, that temperatures could increase 5 to 9 degrees by the year 2100 if present emission trends continue. It also predicts dire consequences for New England, with more extreme hot and cold temperatures, as well as floods and droughts that could affect tourism, cause water shortages, trim forests, and shrink fisheries.
"This report acknowledges that there is a strong consensus among climate scientists that climate change is real," Knobloch said. "It confirms that global climate change is real and underway and that the burning of fossil fuels by humans is a primary driver of that change and that demands action."
The federal government has never regulated carbon dioxide, a gas naturally present in the atmosphere that makes the largest contribution to global warming. Instead, the White House has called for industries to reduce emissions voluntarily. Attorney General Thomas F. Reilly is leading a number of states and environmental groups that are suing the EPA over its failure to regulate the gas that contributes to global warming.