Three-quarters of Alaskans are sold on the existence and seriousness of global warming, but far fewer are convinced that it's caused by human activity, according to a poll commissioned by Alaska Dispatch News.

Those results largely mirror the opinions of Americans at large, according to recent polls, including one recently conducted by CBS and the New York Times that asked the same questions.

Debate over climate change -- and what to do about it -- has become a deeply partisan issue in Washington, D.C., in recent years. Just last week, the U.S. Supreme Court temporarily halted the Environmental Protection Agency's major climate change regulations for the nation's power plants for the duration of an ongoing legal battle. But on the international stage, major countries have agreed that curbing greenhouse gas emissions is essential to lessen the environmental impacts of global warming.

The first question was whether global warming is an environmental problem that is causing a serious impact now, in the future, or never at all. Just more than half -- 54.3 percent -- said global warming is already having serious impacts, and 20.7 percent said the impacts will happen sometime in the future. One-fifth of those polled said global warming will have no serious impacts, and 4.7 percent were not sure.

Where people live in Alaska seemed to affect their feelings on the existence and urgency of climate change. Those polled in rural Alaska, Southeast and Anchorage were more likely to say that climate change is already having serious impacts, compared to people elsewhere in Southcentral Alaska and Fairbanks.

And of those polled in rural Alaska, lessr than 5 percent thought climate change would have no serious impacts, ever.

Alaskans who identified as registered Democrats or Republicans fell along predictable lines: 73.4 percent of Democrats said global warming is having a serious impact now, compared to 27 percent of Republicans.

But the largest portion -- more than half -- of Alaskans polled who said they were registered voters claimed no party. Of those with no party affiliation, a common choice in this state, 64.9 percent said global warming is already having a serious impact.

Across the board, women were much more likely than men to see global warming as a present and serious threat.

Alaskans' answers to the second question indicated that while most believe global warming is happening, only half would attribute it to human activity.

Most climate scientists and a wide range of scientific organizations say that current global warming is caused by human activity, particularly due to burning of fossil fuels and deforestation.

Few of those polled -- 7.4 percent -- answered that global warming does not exist. That's slightly lower than the 9 percent of non-believers who answered the CBS/NYT national poll asking the same questions.

The more common answer -- 38 percent of Alaskans polled -- is that global warming exists but is caused by natural patterns in the Earth's environment.

The remaining 3.8 percent of those polled weren't sure.

Again, answers fell along party lines, with 79.9 percent of Democrats attributing climate change to human activities, such as burning fossil fuels, and 59.6 percent of registered Republicans convinced climate change is natural. Those claiming no party were more divided, with 54.5 percent pointing to human activity and 36.8 percent going with "natural patterns."

The politics surrounding global warming have become distinctly partisan in recent years, a stark change from the failed but bipartisan 2009 effort to enact a cap-and-trade program that would curb carbon dioxide released by power plants.

Members of Alaska's all-Republican congressional delegation vary in their views on climate change, though all three agree that climate change is happening. All three are also opposed to current federal climate change regulations.

Sen. Dan Sullivan and Rep. Don Young reject the idea that humans are the cause of climate change. Sullivan has previously said that there is no scientific consensus on humans' contribution.

"With 7 billion humans on earth, there is definitely an impact on nature. We see it with our own eyes in Alaska," Sullivan said in a statement Thursday. But science "is never 'settled,'" he said, noting opposition to regulations that he said would harm "energy security and economic well-being."

Young firmly believes that climate change is happening but that it is part of the natural cycles of Earth.

"We have to adapt," he said in a July interview. But "the arrogance of mankind thinking they can do everything good and everything bad is beyond my imagination. This is not a new thing, never been a new thing."

Young said plenty of scientists "say this is all hogwash, that man is not involved … I'm not changing. I know exactly where I'm headed. I'll probably be right in the long run."

Young's spokesman, Matt Shuckerow, said Thursday that Young "understands that Alaska is a focal point in the climate change discussion," but rejects the idea that the Obama administration's carbon-cutting regulations "will make meaningful impacts to the climate."

Sen. Lisa Murkowski, chair of the energy committee, attempts to walk a narrower line. She has said that mankind contributes to current global warming but hedges over the extent of that contribution.

Last year, in a flurry of climate amendments on the Senate floor, Murkowski and Sullivan were among the 98 lawmakers who voted for an amendment stating that climate change is not a "hoax." And they both voted against an amendment that said "climate change is real" and "human activity significantly contributes to climate change."

But Murkowski, who was running the floor vote at the time, helped engineer a third option. She and 14 other Republican senators (and 44 Democrats) voted in favor of another amendment that said climate change is real and human activity contributes to it, but eliminated the word "significantly." Sullivan voted nay.

Murkowski's climate change views have proved thorny over the years for environmental activists who once hoped she would prove an outlier in the GOP's stance. Murkowski repeatedly said that climate change is real, and happening in Alaska, and must be addressed. In 2007, she (as did Sen. Ted Stevens) co-sponsored a "low carbon" policy bill offered by Sen. Jeff Bingaman, D-N.M., that contained billions for Alaska's coastal areas dealing with climate change. But during subsequent Senate efforts, Murkowski pushed for allowing drilling in the Arctic National Wildlife Refuge as part of a climate bill, and has since provided mixed answers about the degree to which she thinks mankind is responsible for climate change.

Polling for Alaska Dispatch News was performed by Ivan Moore Research as part of The Alaska Survey, a quarterly, multi-client project. The questions asked on behalf of ADN were only a portion of the questions asked of 750 Alaskans across the state on a variety of topics. The questions were asked by live people over the phone. Of those polled, 300 were on landlines and 450 on cellphones. Questions about political affiliation and ideology were only asked of the 651 people polled who self-identified as registered voters.