Climate Change

Changing Climate
Polar Bears Count

Global Warming. Is it a Global Warning?
Is global warming real? What does it mean to us, to the Earth, and to polar bears? Is there hope?

Scientists clearly agree that the planet is warming. Yet the current debate centers around the cause: Is it part of a natural cycle? Or are human-caused greenhouse gases to blame?

Scientists also clearly state that polar bears are in trouble. So why do naysayers claim otherwise?

Changing Climate
Warming in the Arctic is happening much faster than computer models have been projecting. Large expanses of darker, open water are absorbing more heat and accelerating the process. Since the 1980s, Arctic sea ice has retreated dramatically, with the most extreme decline occurring in the summer melt season.

No one disputes that Arctic sea ice is going through a rapid melt-down. But some reports continue to suggest that it’s all part of a natural cycle not related to the build-up of CO₂ in our atmosphere.

The debate is over. Hundreds of climatologists participating in the Intergovernmental Panel on Climate Change have concluded with at least 90% certainty that warming in the Arctic is linked to human activities that cause a build-up of greenhouse gases. Natural forces, from ocean currents to sunspots, may add to the problem, but they are not primary factors. Read more about this subject and watch our ice loss video.

Records of the build-up of carbon emissions over the past century correlate precisely with the rise in the planet's temperature.

Scientists believe that we have until 2015 before we reach the tipping point with global climate change. The whole planet is in peril from rises in sea levels to extremes in weather conditions that affect crops and water.

 “Conserving energy and finding new energy sources are good insurance policies for the health of the planet,” says Leeann Myers, who serves on PBI's board of directors.

“Humans have solved major problems before including the threat to the ozone layer. We're confident that, given the will, we can reduce carbon emissions and restore the bears' habitat.”

Polar Bears Count
Let's talk about the numbers. Scientists have only rough estimates of historical polar bear populations. But we do know that in the 1960s, their numbers dropped sharply due to overhunting. Populations rebounded after restrictions on polar bear harvests went into effect in the1970s. It was a conservation success story.

Current threat. The current threat to polar bears is entirely different, and more dire. Today's polar bears are facing rapid loss of the sea ice where they hunt, breed, and, in some cases, den. Changes in their distribution or numbers affect the entire Arctic ecosystem.

Results from long-term studies show:

• Canada's Western Hudson Bay population: 22% decline since the early 1980s, directly related to earlier ice break-up on Hudson Bay

• Southern Beaufort Sea population along the northern coast of Alaska and western Canada: decline in cub survival rates and in the weight and skull size of adult males; similar observations made in Western Hudson Bay prior to its population drop

• Baffin Bay population, shared by Greenland and Canada: at risk from both significant sea ice loss and substantial over-harvesting

• Chukchi Sea population, shared by Russia and the United States: declining due to illegal harvest in Russia and one of the highest rates of sea ice loss in the Arctic

Current Trends of the World’s 19 Subpopulations in 2009

This compares with five declining, five stable, and two increasing subpopulations in 2005 (plus seven data deficient), so there's clearly a downward trend.