A study done by oceanographer James Overland and meteorologist Muyin Wang, researchers for the National Oceanic and Atmospheric Administration (NOAA), projects that at the current melting rate, the polar ice cap will by reduced by 40% by 2050.
The Arctic ice cap is melting faster than scientists had expected and will shrink 40 percent by 2050 in most regions, with grim consequences for polar bears, walruses and other marine animals, according to government researchers.
The Arctic sea ice will retreat hundreds of miles farther from the coast of Alaska in the summer, the scientists at the National Oceanic and Atmospheric Administration concluded. That will open up vast waters for fishermen and give easier access to new areas for oil and gas exploration. It is also likely to mean an upheaval in species, bringing new predators to warmer waters and endangering those that depend on ice.
The study, by NOAA oceanographer James Overland and meteorologist Muyin Wang, adds to the increasingly urgent predictions of major ice loss in the Arctic.
Their study and predictions do not extend any hope to reverse the trend.
But Overland’s calculations are based largely on the carbon dioxide that already has been pumped into the atmosphere. That pollution will greatly diminish the ice by 2050, regardless of future curbs on emissions, he said yesterday.
“The amount of emissions we have already put out in the last 20 years will stay around for 40 to 50 years,” Overland said. “I’m afraid to say that a lot of impacts we will see in the next 30 to 40 years are pretty much already established.”
Another study, done by the U.S. Geological Survey, predicts that even with more modest shrinking of the polar ice cap Polar bear populations will drop by 2/3 by 2050.
Two-thirds of the world’s polar bears will disappear by 2050, even under moderate projections for shrinking summer sea ice caused by greenhouse gases in the atmosphere, government scientists reported yesterday.
The finding is part of a year-long review of the effects of climate and ice changes on polar bears to help determine whether they should be protected under the Endangered Species Act. Scientists estimate the current polar bear population at 22,000.
The report, which the U.S. Geological Survey released here, concludes that under middle-of-the road projections for warming the bears will by mid-century be largely relegated to Arctic archipelago of Canada and spots off the northern Greenland coast. The bears would disappear entirely from Alaska, the study said.
The report pessimistically assumes that as the ice cap recedes and traditional habitat is reduced that the bears will not adapt and will disappear. I suspect that is a simplistic scenario.
As the north warms new prey will enter the area and if the bear’s traditional prey becomes available I would think that they would move inland to find new sources of food. Maybe they’ll eat the grizzly and black bears that will begin to expand their territories into a greening north.
To keep things in perspective regarding Polar bears one needs to remember that in the 1950s their population was estimated at 5,000, increased to 8,000 – 10,000 between 1965/70 then to 25,000 in 1984 and then settled on a range of between 20 – 25,000 in 2005. Some of the increase in number can certainly be attributed to better counting techniques in recent years but it certainly shows a healthy bear population at this time and place.
I would be more concerned with the walrus and seal populations but as the first article says:
“This will have a profound effect on the animals that use sea ice all the time, including walrus and polar bears and ringed seals,” he said. “You will actually have a change in the whole ecosystem. You will have winners and losers. Crabs, clams, walrus and bears will not do well. Salmon, pollock and other fisheries that live higher up in the water column will extend their range.”
So if fisheries increase maybe the seal populations will do better than expected.
As the NOAA researchers state:
“We really don’t have a clue how that will look,” Overland said of the species changes. Pollock already moving into the Bering Sea were expected to thrive, for example, but there has been an unexpected loss in species on which the fish feed and an unexpected increase in predator species, he said.
And therein lies the crux of the problem. We know there are changes coming but we don’t really know how severe they will be nor do we know how various species will react and adapt. Hell we can’t predict the local weather accurately a week ahead.
But to be safe you predict the worst case scenario and hope that it scares the government and the public into some kind of an action mode. Although in the case of the NOAA study they have told us that it is too late to do anything anyway. Just get out your fishing rod and head north.