The city of Burlington, Vt., is challenging residents to reduce their household releases of carbon dioxide gas by 10 percent. Brookline officials are mulling an ordinance to require homeowners to plant new trees to absorb carbon dioxide whenever they cut down a significant number. The Boston Public Health Commission just bought five hybrid cars to reduce carbon dioxide and other pollutants.

In the last two years, more than 40 municipal and grass-roots groups - from citizen organizations to religious coalitions - have formed across New England to accomplish locally what they say the Bush administration has failed to do nationally: Slow global warming.

Underscoring the burgeoning effort, clergy led interfaith prayer sessions to end global warming at all six New England State Houses last month.

The activists know their efforts to limit greenhouse gases amount to tiny gestures against the vast scale of the problem, which largely comes from the worldwide burning of coal, gas, and oil. But just as towns declared themselves nuclear weapons-free zones in the 1980s, local climate-change activists say they are laying a foundation for political action that could one day build up to national policy.

''I know it's mostly symbolic, but there is a chance here for the people to change [federal policy],'' said Erik Hoffner, of Shutesbury, a town of 1,800 near Amherst that is developing its own climate-change action plan. Town Meeting this spring overwhelmingly approved a resolution he submitted to conduct a town inventory of greenhouse gas emissions and eventually reduce them.

''We have one tiny Town Hall, one municipal Highway Department with a couple of snowplows. But everyone in our town gets in their cars and drives to Amherst everyday. We can educate people about how they are contributing ... and maybe they will lighten their footprints.''

If awards were given for the most difficult grass-roots environmental campaign, global warming would probably win. Unlike with land preservation or pesticides, people have a difficult time seeing a direct link between their lives and the slow warming of the earth - the average temperature has increased by 1 degree Fahrenheit in the last century. As fossil fuels are burned in power plants and cars, they release carbon dioxide, methane, and nitrous oxide into the atmosphere by the thousands of tons. These gases hover over the earth, trapping rising heat and radiating it back down again like glass in a greenhouse.

But carbon dioxide, the main culprit in global warming, isn't some nasty chemical: it's the fourth most abundant gas on earth. Animals and humans exhale it and it has dozens of uses, including carbonation of soda and beer. For years, activists have complained that it is hard to sustain the public's attention on such a common and slow-acting threat - especially with federal policy makers consistently dismissing the concept of global warming. A new federal report now acknowledges the phenomenon, but the Bush administration has distanced itself from the document. Indeed, President Bush has rejected the international global warming treaty negotiated under his predecessor Bill Clinton.

New England had done the opposite. Tufts University in Medford has a climate change initiative, an institutional commitment to reduce greenhouse gas emissions. A coalition of regional governors and Canadian premiers agreed last August to roll back greenhouse gas emissions in the Northeast to 1990 levels by 2010. More than 20 communities in the region - often with the prodding of groups like the Massachusetts Climate Action Network or Clean Air-Cool Planet in New Hampshire - have become part of Cities for Climate Protection, a program of the International Council for Local Environmental Initiatives.

To belong, each community must add up their total greenhouse gas emissions - and come up with a detailed local action plan to reduce them. For instance, Medford just replaced all its traffic signals with displays that use less energy. Arlington residents just passed a bylaw to have town officials buy the most fuel-efficient cars they can. Boston Mayor Thomas M. Menino has pledged to cut city energy consumption by 10 percent by 2005.

Brookline even figured out how much greenhouse gas each person will produce by 2010 - 12.56 tons a year. In 1995, it was 11.78.

''It's such a nebulous issue, the way to effect any change is to get people to see how their own individual energy consumption, or transportation habits connect to this problem,'' said Briony Angus, climate change project manager in Brookline. In Boston, officials purposely worked on global climate through the Public Health Department to ensure people saw a personal link.

Activists say they can only do so much, however. For example, while Cambridge is committed to purchasing 20 percent of its electricity from so-called green power sources by 2010, the sources may not be around. The city also said it would increase fuel economy in cars.

''Of course, we can't do that without help,'' said Susanne Rasmussen, director of environmental and transportation planning for Cambridge. ''But [these goals] make it easier to demand the federal government take action. A lot of initiatives had to be demonstrated on the local level before they went [national].''

Still, it can be confusing to sort out the motives for some of these actions, since many of them also fight smog and asthma in addition to global warming. As local communities latch on to the global warming cause, everything is being lumped under its banner. Buying bikes for police officers, replacing streetlights with more energy efficient ones - even stopping buses from idling in Roxbury and Dorchester - are now part of global warming campaigns.

''What we're doing is building momentum,'' said the Rev. Margaret Bullitt-Jonas, associate rector of All Saints Parish in Brookline and cochair of a local chapter of Religious Witness for the Earth. The group led the prayer sessions at New England state houses.

''With global warming, the first stage is denial and then once we get past that and realize this is real, people get overwhelmed. But there are things we can do,'' she said.

© Copyright 2002 Globe Newspaper Company

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