Earth hottest in 12,000 years
MOTHER EARTH is beginning to resemble a Peggy Lee song — fever in the
morning, fever all through the night. 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 Proceedings of the National Academy of
Sciences.
The Earth has been warming at a rate of 0.2 degree Celsius per decade for the
last 30 years, according to James Hansen of Nasa’s Goddard Institute for Space
Studies in New York. That brings the overall temperature to the warmest in the
current inter-glacial period, which began about 12,000 years ago.
The researchers noted that a report in the journal Nature found that 1,700
plant, animal and insect species moved pole ward at an average rate of about
1.60 kilometres per decade in the last half of the 20th century.
The warming has been stronger in the far north, where melting ice and snow
expose darker land and rocks beneath allowing more warmth from the sun to be
absorbed, and more over land than water. Water changes temperature more slowly
than land because of its great capacity to hold heat.
“This evidence implies that we are getting close to dangerous levels of
human-made pollution,” Hansen said. Few scientists doubt that the planet has
warmed, though some question the causes of the change.
Hansen, who first warned of the danger of climate change decades ago, said that
human-made greenhouse gases have become the dominant climate change factor. The
study said the recent warming has brought global temperature to a level within
about one degree Celsius of the maximum temperature of the past million years.
“If further global warming reaches two or three degrees Celsius, we will likely
see changes that make Earth a different planet than the one we know. The last
time it was that warm was in the middle Pliocene, about three million years ago,
when sea level was estimated to have been about 25 metres higher than today,”
Hansen said. Global warming Earth warming at a rate of 0.2 degree Celsius per
decade Planet’s temperature has climbed levels not seen in current inter-glacial
period, which began 12,000 years ago If this trend continues, we will see
changes that will make Earth a different planet than the one we know now
*Source:
http://epaper.hindustantimes.com, dated - Thursday, September 28, 2006.*