Just one-out-of-three voters (34%) now believe global warming is caused by human activity, the lowest finding yet in Rasmussen Reports national surveying. However, a plurality (48%) of the Political Class believes humans are to blame.

Forty-eight percent (48%) of all likely voters attribute climate change to long-term planetary trends, while seven percent (7%) blame some other reason. Eleven percent (11%) aren’t sure.

These numbers reflect a reversal from a year ago when 47% blamed human activity while 34% said long-term planetary trends.

Most Democrats (51%) still say humans are to blame for global warming, the position taken by former Vice President Al Gore and other climate change activists. But 66% of Republicans and 47% of adults not affiliated with either party disagree.

Sixty-two percent (62%) of all Americans believe global warming is at least a somewhat serious problem, with 33% who say it’s Very Serious. Thirty-five percent (35%) say it’s a not a serious problem. The overall numbers have remained largely the same for several months, but the number who say Very Serious has gone down.

Forty-eight percent (48%) of Democrats say global warming is a Very Serious problem, compared to 19% of Republicans and 25% of unaffiliateds.

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President Obama has made global warming a priority for his administration. Half (49%) of Americans think the president believes climate change is caused primarily by human activity. This is the first time that belief has fallen below 50% since the president took office. Just 19% say Obama attributes global warming to long-term planetary trends.

Forty-eight percent (48%) rate the president good or excellent on energy issues. Thirty-two percent (32%) give him poor grades in this area.

Sixty-three percent (63%) of adults now say finding new sources of energy is more important that reducing the amount of energy Americans currently consume. However, 29% say energy conservation is the priority.

A growing number of Americans (58%) say the United States needs to build more nuclear plants. This is up five points from last month and the highest finding so far this year. Twenty-five percent (25%) oppose the building of nuclear plants.

While the economy remains the top issue for most Americans, 40% believe there is a conflict between economic growth and environmental protection. Thirty-one percent 31% see no such conflict, while 29% are not sure.

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