Amstrup and University of Washington Arctic sea ice expert Cecilia Bitz set out to prove Bernhardt wrong. The two dove into the scientific literature, looking for links in a chain connecting the smokestack of a coal fired power plant (for example) to the fate of a bear cub in northern Alaska. They emerged with a publication that reads like one part jargon-filled research and one part impassioned advocacy.

Polar bears were labeled as threatened under the Endangered Species Act the same year, but the legal opinion created a loophole for projects, including oil and gas development, to move forward without considering greenhouse gas impacts on polar bears.

Researchers from the University of Washington and Polar Bears International in Bozeman, Montana, have found a relationship between greenhouse gas emissions and the survival of polar bear populations.

The policy-setting 2008 memo was written by Dave Bernhardt, a former fossil fuel industry lobbyist then working as solicitor for the Interior Department who would go on to be President Donald Trump’s secretary of the interior. It required that the projected emissions impacts to polar bears from new proposals, like pipelines or drilling permits, be separated from the effects of historical cumulative emissions.’

Polar bears live in 19 populations across the Arctic and are found in Canada, the United States, Russia, Greenland and Norway, according to conservation organization Polar Bears International.

"We have presented the information necessary to rescind the Bernhardt Memo," first co-author Steven Amstrup, a zoologist with Polar Bears International and the University of Wyoming, told AFP, referring to the legal caveat which was named after an attorney in former president George W. Bush's administration.

New research from the University of Washington and Polar Bears International in Bozeman, Montana, quantifies the relationship between greenhouse gas emissions and the survival of polar bear populations. The paper, published online in Science, combines past research and new analysis to provide a quantitative link between greenhouse gas emissions and polar bear survival rates.

A new study published in Science1 has quantified the relationship between greenhouse gas emissions and the survival of polar bear populations, showing that the more emissions, the less likely the bears are to survive and reproduce.

"We have presented the information necessary to rescind the Bernhardt Memo," first co-author Steven Amstrup, a zoologist with Polar Bears International and the University of Wyoming, told AFP, referring to the legal caveat which was named after an attorney in former president George W. Bush's administration.

“I’m really hoping that this is going to be a major game changer,” said Steven Amstrup, lead author of the study published in Science. Amstrup is chief scientist emeritus at Polar Bears International and an adjunct professor at the University of Wyoming.

New research published in the journal Science has quantified the link between greenhouse gas emissions and the survival of polar bear populations, paving the way for greater protections under the Endangered Species Act.

Bozeman, Montana – August 31, 2023 – In a new paper, scientists with Polar Bears International, the University of Washington, and the University of Wyoming have, for the first time, quantified a direct link between greenhouse gas (GHG) emissions and polar bear survival. Published today in Science, the report, “Unlock the Endangered Species Act to address GHG emissions,” provides a template for estimating the demographic impact of proposed GHG-emitting actions on polar bears—overcoming a loophole in the Endangered Species Act (ESA) that has historically blocked climate considerations.

“We’ve known for decades that continued warming and sea ice loss ultimately can only result in reduced distribution and abundance of polar bears,” says lead author Steven Amstrup, chief scientist emeritus at the non-profit advocacy group Polar Bears International, and adjunct professor at the University of Wyoming, US.

This study has implications beyond the world of struggling polar bears, said Bitz and Amstrup, who is also chief scientist emeritus at the environmental nonprofit Polar Bears International. The same type of analysis could be done for other endangered species harmed by climate change, such as bleaching coral reefs or birds at risk of rising sea levels.

New research from the University of Washington and Polar Bears International in Bozeman, Montana, quantifies the relationship between greenhouse gas emissions and the survival of polar bear populations. The paper, published online Aug. 31 in Science, combines past research and new analysis to provide a quantitative link between greenhouse gas emissions and polar bear survival rates.

"We have presented the information necessary to rescind the Bernhardt Memo," first co-author Steven Amstrup, a zoologist with Polar Bears International and the University of Wyoming, told AFP, referring to the legal caveat which was named after an attorney in former president George W. Bush's administration.

“We’ve known for decades that continued warming and sea ice loss ultimately can only result in reduced distribution and abundance of polar bears,” lead author Steven Amstrup, chief scientist emeritus at Polar Bears International, said in a statement.

It “just seems odd” that polar bears were listed because of the loss of sea ice due to global warming “but emissions have not been considered,” said lead author Steven C. Amstrup, chief scientist emeritus at Polar Bears International and a professor at the University of Wyoming.

Right now, tens of thousands of beluga whales are congregating in the ice-free waters of Canada’s Churchill River and Hudson Bay. The social, bulbous-headed creatures migrate south from the Arctic each summer—and you can watch from the comfort of your home, thanks to online “beluga cams.”