Warnings by scientists that global warming has passed an ominous tipping point, which could see temperatures increase by as much as 8.1° F by 2100 and sea levels rise several feet, is adding fuel to a fire already polarizing the world’s populations and prompting reactions ranging from the sublime to the ridiculous.

For instance, New York’s buttoned-down-collar Wall Street Journal recently ran a story on “Dressing for a Changing Climate.” India’s Bajaj Auto has announced future plans for a direct-injection-gasoline rickshaw. And writing in the Medical Journal of Australia, two academics this month are capturing world headlines by calling for a carbon tax on newborns.

“Every newborn baby in Australia represents a potent source of greenhouse- gas emissions for an average of 80 years, not simply by breathing but by the profligate consumption of resources typical of our society,” says Barry Walters, a professor of obstetrics at the University of Western Australia.

At the other end of the spectrum, the Hudson Institute, a neoconservative U.S. think tank, claims all the shrieking about ice melt at the Poles “is just another day at the scare factory.”

But one group doesn’t consider climate-change warnings a laughing matter. Indeed, the world’s major auto makers believe they, alone, have been singled out by their governments to save the planet.

In the U.S., President Bush this month signed into law an energy bill that includes a 40% increase in federal fuel-economy standards, which will force auto makers to spend billions of dollars to meet the strict measure.

The fleet-wide standard calls for an average 35 mpg (6.7 L/100 km) by 2020 but keeps passenger cars and light trucks classified separately, a distinction the auto industry advocated.

Across the pond, lawmakers in the 27-member European Union are attempting stricter measures to reduce vehicle emissions by regulating grams of carbon dioxide spewed per kilometer. The region’s auto industry reportedly is facing annual penalties of up to $19 billion for violating a mandated fleet average of 130 g/km (45 mpg) of CO2, from the current 160 g/km, by 2012.

Japan currently has no legal mandate on fuel efficiency. Auto makers, instead, are working with the government on an integrated approach that includes greater fuel efficiency through improvements in vehicle technology; better traffic flow, road infrastructure and traffic management; and eco-driving, in which motorists make a conscious effort to conserve fuel.

Although Detroit’s Big Three support the U.S. energy bill’s CAFE increase, General Motors Vice President Bob Lutz says achieving 35 mpg by 2020 presents a significant challenge, noting lawmakers that aggressively backed the legislation lack an understanding of its potential cost to the industry – and to consumers.

“It’s a reach from where we are with smaller cars,” he says. “Politicians in Washington just do not have on-the-ground knowledge.”

Scientists say CO2 and other gases produced by burning fossil fuels trap heat in the atmosphere and cause global warming. The current concentration of carbon in the atmosphere reportedly is about 380 parts per million and increasing by 2 PPM each year.

To stabilize Earth’s climate, the concentration needs to fall to at least 350 PPM, James Hansen, director of NASA’s Goddard Institute for Space Studies, recently told Reuters.

This goal might be achieved by using alternative fuels and new technology. And not just by the auto industry. About 20% of carbon produced by burning coal remains in the atmosphere for at least 1,000 years, Hansen says.

Little wonder some of us need to have a laugh at the world’s expense every once in a while. It’s a way of coping with a matter of such complication and ramification that at first blush it appears to be out of our hands.

No, auto makers should not have to bear the brunt of saving the planet, but nor should our children. It’s something to think about as we make our New Year’s resolution.