Former US senator Bob Smith said, “no.” Brown said, “uh, no.” Former state senator Jim Rubens said, “absolutely, yes,” prompting chuckles from the crowd, according to a sound recording of the event distributed by the American Bridge 21st Century , the Democrats’ main opposition research super PAC.

During the lightning round of a GOP primary forum on Saturday, the moderator asked: “Do you believe that the theory of manmade climate change has been scientifically proven?”

At a debate over the weekend, New Hampshire US Senate hopeful Scott Brown weighed in on climate change, later prompting a sharp response from Jeanne Shaheen, the senator he is hoping to unseat.


On Monday, Shaheen responded to a news story about Brown’s answer.

“Scott Brown is wrong. Climate change is very real, and here in New Hampshire we are already seeing consequences,” she said in a statement.

In 2012, during his race against Elizabeth Warren, Brown was asked about the issue during a televised debate.

Moderator Jon Keller of WBZ asked Brown, “Do you believe climate change is real and, if so, what should the federal government be doing about it?”

Brown replied that he did. “I absolutely believe climate change is real, and I believe there’s a combination between manmade and natural,” he said at the time.

In 2010, during his US Senate special election, the Globe reported Brown expressed skepticism about the causes of climate change.

“I [have] said the climate is always changing,” Brown said at debate with his then-opponent, Attorney General Martha Coakley, the Globe reported. “The question I have is, is it man-made, or does it just happen naturally?”

Asked his current position, spokeswoman Elizabeth Guyton said today in a statement that Brown “believes that the climate is changing by a combination of natural and manmade causes.”


“The real issue is whether we are going to impose a new national energy tax on carbon. Scott Brown says no and Jeanne Shaheen says yes,” she said.

The Intergovernmental Panel on Climate Change, a UN scientific group composed of experts from around the world, regularly releases its assessments on climate change.

“It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century,” according to one of its reports from last year.

Brown is widely expected to win his Sept. 9 primary election. If he does, he’ll face Shaheen on Nov. 4.

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Joshua Miller can be reached at joshua.miller@globe.com. Follow him on Twitter @jm_bos.