WASHINGTON - Global warming threatens to destroy critical polar bear habitat, according to a new study from World Wildlife Fund.
The report Polar Bears at Risk reviews the threats faced by the world's 22,000 polar bears and highlights that human-induced climate change is the number one long-term threat to the survival of the world's largest terrestrial carnivores. The burning of coal and other fuels emits carbon dioxide and other gases that blanket the earth, trap in heat and cause global warming. According to the Intergovernmental Panel on Climate Change (IPCC), climate change in the polar region is expected to be the greatest of anywhere on Earth.
"The WWF report shows that polar bears in Hudson Bay are being impacted by climate change," said Lynn Rosentrater, co-author of the report and climate scientist at WWF's Arctic Program. "The polar bear's basis for survival is being threatened by the reduction of the sea ice. Since the sea ice is melting earlier in the spring, polar bears move to land earlier without having developed as much fat reserves to survive the ice-free season. They are skinny bears by the end of summer, which in the worst case can affect their ability to reproduce."
Increasing CO2 emissions have caused Arctic temperatures to rise by 50Celsius over the past 100 years, and the extent of sea ice has decreased by six percent over the past 20 years. By around 2050, scientists now predict a 60 percent loss of summer sea ice, which would more than double the summer ice-free season from 60 to 150 days. Sea ice is critical to polar bears' survival because it is the platform from where they hunt their primary prey - ringed seals and bearded seals. Diminishing ice cover and longer ice-free periods limit the time the bears have on the ice to hunt and means that they have fewer fat resources to survive during the longer summer season. In addition, lower body weight reduces female bears' ability to lactate, leading to greater mortality among cubs. Fewer than 44 percent currently survive the ice-free season.
Due to the rapid pace of change in the Arctic, there is no time to lose in reducing heat-trapping gases. Significant reductions can be achieved by using existing technologies to increase the energy efficiency of our homes, businesses and automobiles and utilizing clean renewable energy instead of dirty fossil fuels. Particularly, bipartisan support has grown in Congress for a renewable portfolio standard that would ensure that 20% of U.S. energy comes from renewable energy by 2020. President Bush has thus far been opposed to this proposal. World leaders will discuss a similar proposal at the World Summit for Sustainable Development in South Africa this summer. WWF calls on President Bush to support this initiative in Johannesburg.
"Arctic nations that are home to most of the world's polar bears should be leading the charge against global warming," said Jennifer Morgan, director of WWF's Climate Change Program. "Instead, the United States - the world's largest global warming polluter - is essentially ignoring this problem. All eyes will be on President Bush at the upcoming World Summit on Sustainable Development in South Africa this August to test his commitment to sustainable energy solutions for climate change."
The impacts of global warming come on top of problems that polar bears face from hunting, toxic pollution and future oil developments in the Arctic. In some areas, research on polar bears shows a link between high contaminant levels and reduced immune system function.
Polar Bears at Risk
Read a summary of the report, "Vanishing Kingdom: The Melting Realm of the Polar Bear"