Global Temperature Highest in millennia

The planet's temperature has climbed to levels not seen in thousands of years, warming that has begun to affect plants and animals, researchers report in Tuesday's issue of Proceedings of the National Academy of Sciences.

The Earth has been warming at a rate of 0.36 degree Fahrenheit per decade for the last 30 years, according to the research team led by James Hansen of NASA's Goddard Institute for Space Studies in New York. That brings the overall temperature to the warmest in the current interglacial period, which began about 12,000 years ago.