The loss of Arctic ice from glaciers, polar land and sea is declining faster than many scientists expect, as the Intergovernmental Panel on Climate Change's (IPCC) report on oceans and the cryosphere said this week.
Bad news for polar bear populations, a top expert involved in field studies on endangered animals has told The Guardian.
This year's annual minimum of Arctic sea ice tied with the second-lowest rate on record, a mere 1.6m sq miles, and badly affected polar bear populations that live and hunt on the north slope of Alaska, plus those that live on ice floes in the Bering Sea.
“Now the ice has gone offshore we know that the bears are not feeding, and the bears that are forced to land find much to eat. The longer the sea ice is gone from the productive zone the tougher it is on the bears, ”said Steven Amstrup of Polar Bears International's.
In 2015, the group reported that the polar bear population in the Beaufort Sea had declined by 40% over the previous decade. "We can only anticipate that those declarations have continued," Amstrup said.
The loss of sea ice this year was so pronounced early in the season that tagging crews from the US Geological Survey (USGS) concluded that sea ice offshore in the western arctic was too thin and unstable to conduct their studies – the first time the team have withdrawn their studies because of safety issues.
Was a far cry from the two decades to 2010 when Amstrup did two two-month field studies a year.
In recent years, the spring season has also been severely hampered by open water, fog and bad weather.
This year, the trends were repeated. Amstrup said: “The ice in the spring… was really tough this year. What ice there was was thin and rough this year. Part of a progressive trend that we have seen over many years. ”
The global warming situation in the Arctic region, from record heatwaves in Alaska to the loss of more than 60bn tons of ice from Greenland's ice cap over a five-day heatwave this summer, including the largest loss in a 24-hour period since records began.
For both polar bear populations, the circumstances are grim. Those who live on the shore aren't finding much to eat, says Amstrup, and those who live permanently on the ice pack appear to be feeding a lot either.
“They're having a fast fast in the summer and a limit on how long that fast can last. We are already seeing indications of poor cub survival in the Beaufort Sea. An adult bear has a lot of body mass, and it may take a long summer, but young bears do not have the body mass or hunting skills to survive, ”he said.
But because 2019 did not set a record in terms of sea-ice loss, Amstrup stressed, we should not be fooled into thinking that, short of an extreme event, circumstances have stabilized or improved.
Amstrup said funding cuts and the fact that biologists can't get out and study the bears means they may never be able to collect the necessary data to evaluate "just how bad this year was".
Instead, Amstrup says this bad ice year and the warm summer record are symbols of what the future will bring. Bad years like this will become increasingly frequent and bad years will get worse – as long as we allow CO2 levels to continue to rise.
"We know that as greenhouse gas concentrations continue to rise, warmer and more sea ice will continue to rise until polar bears disappear," he said.