Groups like the Cato Institute, a libertarian research organization that defies aspects of climate change, have expressed concern about exaggerated bears, arguing that some research shows that the animals have survived repeated warm spells. But scientists say that during the early early periods, bears probably had important alternative sources of food, especially whales, which they don’t have today.
Conservative groups and other groups have used poignant images of bears on isolated ice floes or on roaming lands in search of food to show the need for measures to reduce warming. Occasionally, however, these images have been shown to be not what they seem.
After National Geographic posted online a video of an emaciated bear collecting trash cans in the Canadian Arctic in 2017, the magazine acknowledged that the bear’s condition may not be related to climate change. Scientists had pointed out that there was no way of knowing what was happening to the bear; He could have been sick or very old.
The new study did not include projections in which emissions were dramatically reduced, said Cecilia M. Bitz, atmospheric scientist at the University of Washington and author of the study. The researchers needed to be able to determine, as accurately as possible, the periods when sea ice would leave a particular region. “If we wanted to see a lot of models, we couldn’t have done that,” said Dr. Bitz.
Andrew Derocher, a polar bear researcher at the University of Alberta who was not involved in the study, said the findings “are very consistent with what we are seeing in empirical studies such as monitoring work in the field.”
“The study clearly shows that polar bears will do better with less warming,” he added. “But no matter what scenario you look at, there are serious concerns about the conservation of the species.”
Of the 19 subpopulations, little is known about some of them, particularly those in the Russian Arctic. Of the subpopulations that have been studied, some, generally those in areas with less ice loss, have shown little population decline so far. But others, especially in the southern Beaufort Sea, in northeast Alaska, and in western Hudson Bay in Canada, have been severely affected by the loss of sea ice.
