The ads campaign, launched in late March, is being run for free throughout U.S., said Fred Krupp, Environmental Defense's executive director.

    "The best we can hope for is to prevent the worst, such as catastrophic climate change and a drastic rise in sea levels," say leading climate scientists.

    Signs of global warming are three times more apparent in Antarctica than across the rest of the planet, according to a new study of the British Antarctic Survey.

    Scientists estimate that atmospheric temperatures over Antarctica in the winter have risen by about 1.5 degrees 1.5 Celsius in the last 30 years due in large part to gas emissions. 

    Another study in the journal Science last month said the melting of the Greenland's polar ice, which is happening faster than originally thought, could trigger a 1- to 3-foot rise in global ocean levels. 

    Stopping or delaying disasters, which are believed to be just in decades, would require actions.

    "Together, if we take a concentrated action as a people, we might be able to slow it down enough to avoid these surprises," said scientists.

    Nearly two dozen computer models show that by 2100, the average yearly global temperature will be 3 to 6 degrees Fahrenheit higher than now.

    But Environmental Defense hopes to convince people they can do something about global warming, that there's still time. "There's a certain amount of warming that's inevitable, but that doesn't mean that we can't avoid the really dangerous things that are happening." ¡¡

    £¨Agencies£©