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Foreshadowing potential climate chaos to come, early global warming caused unexpectedly severe and erratic temperature swings as rising levels of greenhouse gases helped transform Earth, a team led by researchers at UC Davis said Thursday.

The global transition from ice age to greenhouse 300 million years ago was marked by repeated dips and rises in the amount of carbon dioxide in the atmosphere and wild swings in temperature, with drastic effects on forests and vegetation, the researchers reported in the journal Science.

They lived in resplendence, half a world apart, before meeting their respective downfalls within decades of one another. Now a new theory suggests that the decline of the Tang Dynasty in China and that of the Mayan civilization in Mexico may both have been due to the same worldwide drought.

The events may both be the result of a southward shift in rain patterns that deprived the entire northern tropics of summer rains, suggest researchers led by Gerald Haug of Germany's National Research Centre for Geosciences in Potsdam. The hardship caused by this drought could have been a key factor in the declines of the two cultures, they suggest.

the Mayan civilization in Mexico may both have been due to the same worldwide drought.

Bruce wrote:http://www.nature.com/news/2007/070101/ ... 101-2.html

They lived in resplendence, half a world apart, before meeting their respective downfalls within decades of one another. Now a new theory suggests that the decline of the Tang Dynasty in China and that of the Mayan civilization in Mexico may both have been due to the same worldwide drought.

The events may both be the result of a southward shift in rain patterns that deprived the entire northern tropics of summer rains, suggest researchers led by Gerald Haug of Germany's National Research Centre for Geosciences in Potsdam. The hardship caused by this drought could have been a key factor in the declines of the two cultures, they suggest.

A birdseed factory in Shropshire, a holy lake in China, Baltic Sea fish and new-born hedgehogs have emerged as the first tangible victims of climate change in the year which forecasters predicted this week would be the warmest on record.

The CJ Wild Bird Foods company near Shrewsbury has announced that the demand for its products has all but disappeared, because the mild winter had maintained an alternative supply of berries for finches, tits and other species. Some species, such as the dunlin and purple sandpiper, are disappearing from Britain as they can find enough warmth in Scandinavia. The company, which said fears of bird flu has also discouraged the public from setting up bird feeders, has laid off 22 workers.

The warmer environment is also contributing to the gradual disappearance of the vast Lake Qinghai, a holy site for Tibetans in the remote western province of Qinghai. Despite a Chinese government pledge of £442m to stop the lake shrinking, it will have vanished in two centuries, according to a report by the China Geological Survey Bureau (CGSB). Glaciers on the nearby Qinghai-Tibet plateau have also shrunk by 131.4 sq km annually in the past 30 years. "What that means is that an area of glacier equivalent to twice the size of the Beijing downtown area disappears every year," said the CGSB. A further 13,000 sq km of glacier - nearly 28 per cent of the total glacier area - will disappear by 2050 if no protective measures are taken.

The index was calculated from nine separate indicators of climate change. These included years that are hot, dry or wet overall, and also those in which the months of June, July and August, or December, January and February, would be extremely warm, dry or wet. Bättig and her colleagues divided the world into squares measuring 375 by 375 kilometres, and for each indicator they identified the extreme climate events that in the period 1961 to 1990 would have been expected to occur in 1 year in 20.

The transition from an ice age to an ice-free planet 300 million years ago was highly unstable, marked by dips and rises in carbon dioxide, extreme swings in climate and drastic effects on tropical vegetation, according to a study published in the journal Science Jan. 5.

"This is the best documented record we have of what happens to the climate system during long-term global warming following an ice age," said Isabel Montañez, professor of geology at the University of California, Davis, and lead author on the paper. But she added that these findings cannot be applied directly to current global warming trends.