US opponents of climate change action are seizing on a record snowfall in Washington in hopes of killing legislation to curb carbon emissions, which already faced uncertain political prospects.

Environmentalists have launched a swift counter-attack, pointing out that Olympics host Vancouver is facing a dearth of snow and saying the extreme weather may in fact offer proof, not a rebuttal, of changing climate patterns.

With Washington and other eastern cities digging out from the heaviest snow in decades, conservatives have gone on the offensive and mocked leaders who warned about the planet's heating -- in particular, former vice president Al Gore.

"It's going to keep snowing in DC until Al Gore cries 'uncle,'" Senator Jim DeMint, a Republican from South Carolina, wrote on micro-blogging website Twitter.

Republican Senator James Inhofe of Oklahoma, a leading climate change skeptic, joined his family in building an igloo on Capitol Hill with signs reading "Al Gore's new home" and "Honk if you love global warming."

"I know that somebody is going to end up tearing it down," Inhofe said on his blog. "Because there are a lot of people who can't take a joke."

President Barack Obama sharply changed US policy on climate change when he took office last year. The House of Representatives in June approved the first nationwide plan to force cuts in carbon emissions blamed for global warming.

But the legislation has bogged down in the Senate, where Obama's Democratic Party last month lost a seat to a Republican who opposes action on the heat-trapping gases.

Senator John Kerry, the leading force behind the legislation, dismissed suggestions that the snow could bury the bill.

"The inside-the-Beltway conventional wisdom that this issue has stalled is dead wrong," said Kerry, a Democrat from Massachusetts.

"Comprehensive legislation will not only speed economic recovery, but it will put our country on the path to sustainable long-term economic growth," Kerry said.

But Senator Charles Grassley, a Republican from Iowa, said he heard Obama tell Democrats the Senate bill would not include a so-called "cap-and-trade" system -- which would restrict emissions but allow a trade in credits.

"I think that the chances of that going through are very, very bad," he said, pointing in part to a backlash to the unruly Copenhagen summit in December.

Environmentalists accused climate skeptics of misunderstanding the science behind snowstorms.

While few meteorologists linked the blizzard directly to climate change, some said it showed the El Nino effect -- where unusually warm sea surface temperatures in the Pacific Ocean move east, pulling rainfall along with them.

Jeff Masters, director of meteorology at the Weather Underground website, said that the snow proved little more than that "we get pretty darn cold in the winter."

"If it's cold enough to snow, you will get snow," he said. "We still have winter, even though temperatures have warmed on average about one degree Fahrenheit (0.5 Celsius) over the past 100 years."

The Obama administration has pledged to move ahead on climate change. It has signed on to an accord from the Copenhagen summit with a pledge to cut US emissions by 17 percent by 2020 from 2005 levels.

A 2007 report by a UN panel of scientists said that human-caused climate change was unequivocally a fact and that it would threaten droughts, floods and other severe weather along with the survival of entire species if unchecked.

The IPCC has since come under fire after admitting that one assertion, that Himalayan glaciers were at risk, was unsubstantiated. Leaked emails from the scientists also showed what critics believe are attempts to restrict debate.

"The IPCC's 'consensus' is slowly eroding away in the face of embarrassing disclosures about the poor quality of data and information it has used to make projections about climate change," Inhofe said.

But the panel has stood by the bulk of its work, as have policymakers in most nations.