Click to enlarge.

Keystone XL. The survey found that two-thirds of Americans (66%) favor building the pipeline, which would transport oil from Canada’s oil sands region through the Midwest to refineries in Texas. 23% oppose construction of the pipeline.

Support for the pipeline spans most demographic and partisan groups, according to Pew. Substantial majorities of Republicans (82%) and independents (70%) favor building the Keystone XL pipeline, as do 54% of Democrats. There is a division among Democrats: 60% of the party’s conservatives and moderates support building the pipeline, compared with 42% of liberal Democrats.

Fracking. The survey found mixed opinions about increased use of fracking, a drilling method that uses high-pressure water and chemicals to extract oil and natural gas from underground rock formations. About half (48%) of Americans favor the increased use of this process, while 38% are opposed.

There are regional differences in opinions about the increased use of fracking. More than half of those who live in the Midwest (55%) and South (52%) favor the increased use of fracking; there is less support in the West (43%) and Northeast (37%).

While men favor the increased use of fracking by a 55% to 34% margin, women are divided (41% favor, 42% oppose).

Twice as many Republicans (66%) as Democrats (33%) favor the increased use of fracking. Independents, by a 51% to 36% margin, support the increased use of fracking.

Percentages on views of seriousness of global warming over time. Data: Pew. Click to enlarge.

Global warming. 69% said there is solid evidence that the average temperature on earth has been getting warmer over the past few decades—little changed from last October (67%), but up 12 points since October 2009. Four years ago, just 57% saw solid evidence of global warming and 36% said it was mostly caused by human activity.

Among those who see evidence of global warming, more say it is caused mostly by human activity (42% of the public) than by natural patterns in the earth’s environment (23%). 27% say there is no solid evidence of warming.

However, the percentage of Americans who say that global warming is a very serious problem has slipped six points, from 39% to 33%, since last October. Current opinions about whether global warming is a very serious problem are similar to those in 2009 and 2010.

Pew noted that there has been a sizable partisan gap in views about whether there is solid evidence of global warming since the Pew Research Center began asking this question in 2006.

In the current survey, almost twice as many Democrats (87%) as Republicans (44%) say there is solid evidence that the average temperature on earth has been rising. Further, Democrats are three times as likely as Republicans to say that human activity is mostly causing global warming (57% vs. 19%).

Beyond the wide gap between parties in opinions about global warming, there also are differences among Republicans and Democrats.

Moderate and liberal Republicans are far more likely than conservative Republicans to say there is solid evidence of global warming (57% vs. 37%) and are more likely to say it is mostly happening because of human activity (27% vs. 16%).

Most liberal Democrats (92%) and conservative and moderate Democrats (85%) say there is solid evidence of global warming. But far more liberal Democrats (72%) than conservative and moderate Democrats (51%) say the earth is getting warmer mostly because of human activity.

Most Americans continue to say that global warming is either a very serious problem (33%) or a somewhat serious problem (32%). However, the percentage saying it is a very serious problem has declined six points (from 39%) since October 2012.

Current views about whether global warming is a serious problem are similar to those in 2009 (35% very serious problem) and 2010 (32%). From 2006 through 2008, more than four-in-ten viewed global warming as a very serious problem.

About half of Democrats (48%) say global warming is a very serious problem, an eight-point decline from 56% last October. The percentage of independents saying global warming is a very serious problem also has slipped, from 39% to 31%. Just 14% of Republicans say global warming is a very serious problem; in October, 19% of Republicans expressed this view.