A recent series of news stories suggests that polar ice caps are melting "faster than expected," and that this phenomenon may result in the extinction of one of humanity's favorite animals, the polar bear. Apparently polar bears need to be able to migrate onto the ice to fish for food, and this shift in climate is already beginning to interrupt their ability to feed themselves.Most rational scientists believe this shift in arctic climate is due to global warming resulting from the greenhouse effect, which is produced largely by automotive emissions.While some scientists are speculating that it may be too late to reverse the trend of global warming, at least in the short run, others believe that we need to do something drastic - now - to avoid environmental disaster.

Internal combustion engines are the big culprit here; they emit a variety of gasses into the air as they burn fuel, including carbon dioxide, one of the main causes of the greenhouse effect. Two automobile manufacturers, Toyota and Honda, have created gas-electric hybrid vehicles - the Prius by Toyota, at this point the top-rated hybrid designed to have the lowest emissions, and several designs by Honda, including the newly engineered Honda Civic - smarter, sexier, more fuel-efficient, and with lower emissions, than its earlier versions.Ford offers a hybrid SUV in its new Escape, and even Lexus has come out with a luxury hybrid.Many cars on the market today can burn a gasoline-ethanol blend, which can lower emissions.

As a matter of fact, any gasoline-powered vehicle can tolerate blends of up to 10 percent ethanol, while many can use E85, an ethanol - gasoline blend containing 85 percent ethanol. The Dodge Caravan and the Chrysler Sebring are only two of many current model cars on the market which can burn E85.One problem is that ethanol, particularly E85, is not readily available everywhere. Additionally, some critics have dismissed ethanol as impractical, claiming that ethanol requires more energy to create than it produces.As global political and environmental concerns heighten the demand for alternatives to petroleum-based fuels, scientists will continue to work on more efficient ways of producing ethanol.

Diesel cars can run on biodiesel, a combination of regular diesel fuel and vegetable oil - based fuel; some cars are being run on D100, which is 100 percent vegetable oil. Two concerns with biodiesel are, again, availability, and the emissions of nitrogen oxide, another culprit in the greenhouse effect. While biodiesel is promising, and has the added benefit of reducing dependence on foreign oil, any real effort to make biodiesel cars more popular will have to come with much stricter emissions standards which greatly reduce nitrogen oxide content.An interesting irony is that the EPA's mileage standards, while having been criticized as inaccurate, are actually a good way to gauge automobile emissions.That is because the EPA actually measures the emissions exiting the vehicle as a way to gauge automobile mileage.

While a high MPG rating may not necessarily be accurate in terms of your gasoline usage, it's actually a pretty good way to choose a car with lower emissions.Global warming endangers more than polar bears; as the polar ice caps melt, the temperature of the oceans rises along with the sea level. Warmer ocean temperatures fuel hurricanes, making level three, four, five and hurricanes more frequent.

And many millions of people, in Micronesia, Southeast Asia, and around the world live in areas literally inches above sea level; their habitat, and possibly their lives, are threatened by the rise in sea level accompanying global warming.While driving a car with low gas emissions isn't going to completely solve the problem of global warming, it's a contribution that any consumer shopping for a new car can decide to make.

blogspot.com She may be reached at amfredenburg@yahoo.com.

By: Aldene Fredenburg