The authors of the paper also came under fire. Freedom of information requests were filed at universities for three of the authors’ correspondence, with at least one request by Dr. Crockford. (Two of the requests have been turned down, while one, at the University of California, Davis, is still under review.) And Hans LaBohm, editor of the blog ClimateGate.nl, wrote to the Royal Netherlands Academy of Arts and Sciences demanding that Jeffrey A. Harvey, an ecologist and the article’s lead author, be reprimanded for conduct “unworthy of serious scientists.”

Dr. Harvey said the paper grew out of the increasing frustration he and other scientists felt about the spread of false information, the disregard of established evidence and the harassment of researchers that has in some cases accompanied the public debate on climate change.

By contesting scientific findings about polar bears, denialists hope to instill doubt about climate science as a whole, Dr. Harvey said. “Every time these deniers make some outlandish claim in the media and we don’t respond to it, it’s like a soccer match and we’ve given them an open goal,” he added.

Michael Oppenheimer, a professor of geoscience and international affairs at the Woodrow Wilson School at Princeton who was not involved with the article, said he was not surprised to see scientists banding together against climate change denial.

“Some climate scientists basically have had enough of being punching bags,” Dr. Oppenheimer said.

He added that scientists have a right to publicly question someone’s expertise, as the authors did with Dr. Crockford. “If people are going to make claims that are contrary to scientific understanding, then it’s perfectly appropriate to call them out for it,” he said, “because in this day and age, where there are so many information sources, it’s often difficult to identify who’s a real expert.”

Although many contrarian websites pick up discussion about polar bears from Dr. Crockford’s blog, the article noted that she has no demonstrated expertise in climate science or its effects on polar bears. The credentials of many of the BioScience paper’s authors include long lists of published, peer-reviewed articles and studies on these subjects.

Dr. Crockford is an adjunct professor in anthropology at the University of Victoria in British Columbia. Her fields of study include evolution and paleoecology. She has published some peer-reviewed articles that touch on polar bears. She has also published reports and articles that have not been peer-reviewed, like those through the Global Warming Policy Foundation.