Polar bear survival linked to greenhouse gas emissions

Unveiling the direct impact of emissions on Arctic wildlife

Climate change has long been suspected of affecting polar bear populations, but a new study published in Science, “Unlock the Endangered Species Act to address GHG emissions,” offers the first quantifiable link between greenhouse gas emissions and the survival of these Arctic animals.

“We’ve known for decades that continued warming and sea ice loss ultimately can only result in reduced distribution and abundance of polar bears,” “In this paper, we reveal a direct link between anthropogenic GHG emissions and cub survival rates.”

Dr. Steven Amstrup, chief scientist emeritus at Polar Bears International.

Closing the legal gap

The new report outlines an approach 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.

Beyond the Bernhardt memo

In 2008, then-Solicitor of the Department of the Interior, David Bernhardt, issued a memo claiming that the impact of emissions from individual projects could not be separated from historic emissions. This limitation has been addressed in the new study.

Scientific foundation for policy change

The study gives the Department of Interior the scientific basis needed to start including GHG emissions in reviews of all new projects, thus potentially rescinding the limitations set by the Bernhardt Memo.

Polar bears

Building upon a 2020 Nature article, the paper quantifies the number of fasting days caused by a specific amount of CO2 emissions. This sets a temporal limit for polar bear persistence, revealing when demographic impacts will likely occur across different Arctic subpopulations.

Broad implications for other species and habitats

The methodology in the paper could also be applied to other ecosystems and species, beach-nesting species and habitats, impacted by rising sea levels such as sea turtles, offering a tool for policymakers and environmentalists around the world.

Long-view perspective

The study removes barriers that have prevented action on climate change, giving scientists, policymakers, and citizens the tools to make more informed decisions about our impact on the planet.


More Aerospace


More Agriculture


More Automotive


More Energy


More Technology


More Environmental