Earth close to hottest climate in million years

SMH


September 26, 2006 - 1:23PM


The Earth's rapid warming has pushed temperatures to their hottest level in nearly 12,000 years and within a hair's breadth of a million years, a study by the US space agency showed on Sunday.

Global warming, which has added 0.2 of a degree a decade over the past 30 years, has caused temperatures to reach and now pass through the warmest levels in the current interglacial period, which lasted almost 12,000 years, said the study led by James Hansen, a leading climatologist at NASA's Goddard Institute for Space Studies.

The study, published in the September 26 of the journal Proceedings of the National Academy of Sciences, said that Earth was now within about 1 degree of the maximum estimated temperature of the past million years.

The National Aeronautics and Space Administration researcher said that was the most important finding of the team's research.

"That means that further global warming of 1 degree Celsius defines a critical level. If warming is kept less than that, effects of global warming may be relatively manageable. During the warmest interglacial periods, the Earth was reasonably similar to today," Hansen said.

"But if further global warming reaches 2 or 3 degrees Celsius, we will likely see changes that make Earth a different planet than the one we know."

Hansen pointed out that the last time it was that warm was in the middle Pliocene, about 3 million years ago, when the sea level was estimated to have been about 25 metres higher than today.

The researchers recalled that a study published in 2003 by the British science journal Nature showed that 1700 varieties of plants and animal and insect species had migrated toward the North Pole at an average six kilometres a decade in the second half of the 20th century.

AFP