Polar bears are one of the most prominent symbols of man-made climate change, and it’s not difficult to see why. Little garners more empathy than the sight of an animal watching on helplessly as its home literally disintegrates into the sea.
Plenty of studies have detailed just how quickly their icy habitats are disappearing, and a new paper in the journal Cryosphere sadly reveals just how desperate their plight is. There are 19 separate polar bear populations that live throughout the Arctic, and it just so happens that every single one of them is experiencing increasingly early ice loss.
A team from the University of Washington (UW) scoured through 35 years of satellite data, which recorded the daily sea ice concentrations. Polar bears use sea ice in both summer and winter for hunting their aquatic prey and for mating – without it, they would almost certainly die out.
Sadly, the researchers discovered that the total number of ice-covered days has been declining year-on-year since at least 1979. In fact, every decade since then, there have been anywhere between seven to 19 fewer ice days.
In addition, sea ice concentration during summer months has fallen in all regions, from between 1 and 9 percent per decade. This means that polar bears have been spending more time on land fasting than ever before.
Time lapse of relative age of Arctic sea ice since 1990. The oldest ice is white, and the seasonal ice is dark blue. Note how much old ice has disappeared as of late. NOAA Climate.gov via YouTube
Most importantly, across all regions, spring melting has begun increasingly early over time. Thawing began three to nine days earlier per decade, which adds up to seven total weeks of total loss of sea ice in just 35 years.
“We expect that if the trends continue, compared with today, polar bears will experience another six to seven weeks of ice-free periods by mid-century,” co-author Harry Stern, an Arctic sea ice researcher at UW, said in a statement.
The shocking loss of sea ice has been known for some time, but the rate of change recently has been nothing short of ludicrous. In Greenland, for example, the ice began thawing this year back in April at a speed that was more reminiscent of mid-June. Researchers monitoring the area thought it might have been a technical fault, and they had to “check that [their] models were working properly.”
This new study is one of the most precise measurements of Arctic sea ice to date, and it only adds to the weight of evidence revealing how quickly the Arctic is disappearing. Without it, much of the incoming solar radiation won’t be reflected back into space, and the planet will begin to warm at a truly unfathomable pace.
Polar bears live here, so naturally this is all terrible news for them. Without extensive sea ice, they wander onto the land, where they scavenge for food and, increasingly, mate with grizzly bears to form unusual hybrids.
The International Union for Conservation of Nature (IUCN) lists them as “vulnerable,” which means that the risks of them being wiped out are still present, but they aren’t in anywhere near as much danger as, say, the Asian elephant or the Eastern gorilla, which are “endangered” and “critically endangered,” respectively.
Thanks to an unusually coordinated international effort to protect the polar bears, including regulations on hunting, their numbers have stabilized recently. However, it’s looking increasingly likely that climate change’s unrelenting march will see their numbers evaporate once more, along with their home.
Hey there, little fella! AndreAnita/Shutterstock