Nissan's polar bear mascot gives a hug to a Nissan LEAF fan at the ceremony celebrating the first delivery of the electric car, on Dec. 11, 2010.

Using the endangered polar bear as the mascot for an electric car marketing campaign strikes a powerful emotional chord, but it has its risks. Critics will argue that a car company should steer clear of an overtly environmental message trying to link cars, even electric ones, with saving the planet. Yet, according to Steve Amstrup, senior scientist with Polar Bears International, and the retired head of polar bear research for the U.S. government, the Nissan LEAF polar bear serves a higher educational purpose.

“Nissan realized that polar bears, perhaps more than anything else, have captured the human imagination,” Amstrup said. “And because polar bears are one of the first really iconic species that’s likely to go away if we don’t change our ways, it’s a real opportunity.” I had a chance to speak with Amstrup, who attended the San Francisco celebration of the first LEAF delivery last weekend.

Amstrup told me that the principle threat to polar bears is greenhouse gas emissions. “Our studies are conclusive on that, and the only way to save polar bears for the future is to reduce our greenhouse footprint substantially,” Amstrup said. “Vehicles like the LEAF are a great step forward.”

He said that transportation contributes more than 20 percent of greenhouse gases on a national basis, and around 50 percent in California.

The consequences of global warming are dire for polar bears, according to Amstrup. The summertime sea ice, upon which polar bears rely for survival, has been declining by about 10 percent a decade for the last several decades. Studies conducted by Polar Bears International show that, if we continue on the same course, that two-thirds of the world’s polar bears could disappear in 50 years, and the entire population could be wiped out by the end of the century.

The problem goes beyond the cute and cuddly polar bear. “We haven’t overlooked that the things that will benefit polar bears will have benefits to all segments of society and the ecology clear across the globe,” Amstrup said. He then rattled off a list of evidence that global warming is already taking its toll and will get worse unless action is taken: rising sea levels, continued ocean acidification, expansion of deserts, the loss of production ability from many of our major farmlands, severe storm events, and severe droughts.

“The changes are occurring more rapidly in the arctic than anywhere,” he warned. “The fact that polar bears could disappear in the next 100 years is a harbinger of things yet to come elsewhere.”

On a slightly more hopeful note, Amstrup said, “This is a problem that humans have created. And humans can fix it.”

To mark the occasion of the delivery of the first units of the LEAF, Nissan is donating $25,000 to the World Wildlife Fund.