Sens. John McCain and Hillary Clinton, touring Alaska this week to view melting permafrost and shrinking glaciers, said the evidence is mounting that global warming is real and human activity is significantly to blame.

"The question is how much damage will be done before we start taking concrete action," McCain, R-Ariz., told reporters at the Hotel Captain Cook Wednesday morning. "Go up to places like we just came from. It's a little scary."

Clinton, D-N.Y., said the scientists and Native people she's spoken to on this trip to Alaska and Canada's Yukon Territory make the case with convincing and moving particulars.

"So I don't think there's any doubt left for anybody who actually looks at the science," she said. "There are still some holdouts, but they're fighting a losing battle. The science is overwhelming."

Among those holdouts, though, is Alaska's entire delegation to Congress -- Sens. Ted Stevens and Lisa Murkowski and Congressman Don Young -- who did not accompany the senators on their tour.

The Alaskans have opposed mandatory limits on the emission of carbon dioxide and other greenhouse gases, saying they're not convinced that humans are largely to blame.

That would put them outside the scientific mainstream.

The National Academy of Sciences and the academies of 10 other nations issued a statement this summer saying there is strong evidence that significant global warming is under way and that "it is likely that most of the warming in recent decades can be attributed to human activities."

Whatever the cause, almost everyone agrees the Arctic is warming faster than the rest of the world, and the effects in the North can seem dramatic, which is why Clinton, McCain and two other Lower 48 senators came. Sen. Susan Collins, R-Maine, said the Arctic is the canary in the mine shaft of global warming, "crying out to us to pay attention to the impact."

The group flew over Canada's Yukon territory and saw forests decimated by spruce bark beetles -- believed to grow profusely because of warm weather.

"It's just heartbreaking to see the devastation," Clinton said.

She was struck by the account of a 93-year-old woman she met at a fish camp they helicoptered to from Whitehorse, Yukon. The woman told her she'd been fishing there her whole life but that lately the fish have strange bumps on them, growths Clinton said sounded like some sort of tumor.

They also went to Barrow, the northernmost city in the United States, and met with scientists and Inupiaq Eskimo residents concerned about rising sea levels and other changes. The senators headed to Seward Wednesday to see shrinking glaciers in Kenai Fjords National Park.

Murkowski doesn't dispute Earth is warming or that emissions play a role, only the size of that role, her spokeswoman, Kristin Pugh, said Wednesday. Murkowski welcomed the senators with a dinner she hosted Tuesday night at the Turnagain home of former Gov. Bill Sheffield. After dinner, Clinton and Murkowski walked back to the Captain Cook along the city's Coastal Trail, Pugh said.

Last year, the Alaska delegation disputed an international report by more than 300 scientists that said "human influences ... have now become the dominant factor" in global warming.

Young dismissed the "so-called study" as ammunition for fear mongers.

"I don't believe it is our fault. That's an opinion," Young said in November. "It's as sound as any scientist's."

In an interview with KTUU-Channel 2 News this week, Young said the globe is going to change no matter what humans do.

"But to have people come down and talk about we gotta do this, we gotta change that, we don't use Freon anymore, you don't use underarm deodorant, you can't do these kinds of things -- you know, that is pure nonsense," Young said.

Murkowski said she got her most definitive answer to date at a Senate hearing last month, when a climate expert told her that "nearly all" the warming in recent decades is due to human activity. She said the degree of human causation is a matter of debate, however, and she wanted more evidence before she could support something like mandatory emission limits, which could slow the economy.

McCain and Sen. Joe Lieberman, D-Conn., have sponsored the "Climate Stewardship and Innovation Act," which would require electric utilities and other companies to keep greenhouse gas emissions to what they were in the year 2000.

Stevens, who opposes mandatory limits, has said any such legislation would have to go through him because he chairs the Senate Commerce Committee.

Sen. Lindsey Graham, R-S.C., the fourth senator at the Anchorage press conference Wednesday, said he is on the fence about global warming legislation but said he was moved by what he heard on the trip.

"Climate change is different when you come here, because you see the faces of people experiencing it in Alaska," he said. "If you can go to the Native people and listen to their stories and walk away with any doubt that something's going on, I just think you're not listening."

As for Rep. Young's dismissive comments about the issue, "All of us who know Don know that he's just being Don," said Graham.

One of the climate-related questions Alaska's senators are facing is what to do for villages like Shishmaref, which are suffering coastal erosion. Moving them is projected to cost hundreds of millions of dollars.

McCain, a constant critic of congressional spending, said he thinks American taxpayers will be generous to such villagers, as they are to hurricane victims in Florida.

But, he said, people asking for money to fix a problem should be willing to address the root cause.

"So far, some of my colleagues are not eager to do so," he said.

Commentary:
The scientific evidence in favor of "global warming" is clear and self evident. What to do about it is the question. It appears most of the GOP remains in la-la land while it goes about distorting the science of evolution and global warming so they can pander to the oil industry and intolerant conservative Christians.

I spoke to two of my nieces last night about evolution. Neither of them knew what it was. The watering down of science continues and it's dangerous. Without the ability to look objectively at the past, how can they find solutions for their future?