By 2100, there could be no polar bears left.
It’s a staggering statistic, but researchers say their new understandings of sea ice melt and polar bear diets show that some polar bear populations are already seeing reproductive loss.
“We are most likely going to lose every single polar bear population in the world,” says Péter Molnár, researcher at the University of Toronto Scarborough and lead author of this most recent study on polar bears.
“If we manage to do some moderate mitigation, we'll still lose some of the southern polar bear populations, but it gives the northern ones a chance.”
Molnár’s research began in 2015, but he says crucial research elements and methodologies he used have been in the works since 2005. The 15 years of work prior to his was necessary to fully understand and predict the future of polar bears.
“It has been clear for a long time that polar bears are going to be impacted by climate change. All we’re doing is putting timelines on things researchers have anticipated for quite some time already,” says Molnár.
As of July 15 data pulled together by the National Snow and Ice Data Center, Arctic sea ice shrunk by 330,000 square kilometres below the 2011 record low for that date..
According to NSIDC, through the first half of July 2020, sea ice coverage declined by an average of 146,000 square kilometers per day, which they say is “considerably faster” than the 1981 to 2010 average rate of 85,900 square kilometers per day.
There are 19 polar bear populations in the world, with 13 of those in Canada — and they all rely on sea ice to stay close to the water where their prey base is. In Northern Ontario, around Hudson Bay where the ice melts every year, Molnár says the polar bears only have about ten years left.
“We weren’t surprised to see there was only a decade left,” says Molnár. “Climate change is already happening in these regions. We’re projecting backwards in time and one of the things the model says is that there should be no reproductive impacts … but then [reproduction] started to decline. Ultimately the population declined by about 22 per cent [since we’ve been watching].”
The loss of sea ice forces polar bears onto the land and away from their food sources for longer and longer periods of time. The prolonged fasting and reduction in nursing of polar bear cubs will ultimately result in reproductive loss, says ?.
According to the World Wildlife Foundation, 95 per cent of the thickest Arctic sea ice is already gone — and it’s all (no) thanks to greenhouse gas emissions.
“Human activities are at the root of this phenomenon,” says a WWF report about the ice melt. “Specifically, since the industrial revolution, carbon dioxide and other greenhouse gas emissions have raised temperatures, even higher in the poles, and as a result, glaciers are rapidly melting, calving off into the sea and retreating on land.”
WWF scientists say the Arctic could be entirely ice-free during the summer by 2040.
“Given that we’re already observing these effects and the ice-less periods are getting longer, it’s not a surprise the effects will amplify in the future,” says Molnár. “Science shows you the consequences of your actions. If we don’t mitigate the effects of greenhouse gases, the polar bears will suffer.