Fri, May 16, 2008 The Straits Times
Earth off balance and it's our faultWASHINGTON -
HUMAN-GENERATED climate change is altering plant and animal life on every continent, a vast global study has found,
with flowers blooming and birds breeding earlier, and polar bears becoming cannibals.
Hundreds of previous studies have noted these specific changes, and most suggested a link to human-caused, or anthropogenic, global warming.
But the new study, published in the journal Nature, goes further,
trawling hundreds of papers published in peer-reviewed journals dating back to the 1970s, and correlating them with temperature changes.
The researchers uncovered a close relationship between temperature shifts between 1970 and 2004 and changes in plants and animals as well as physical changes like the
retreat of glaciers and the water level in desert lakes.
'When you look at all of the glaciers and all of the snowpack and all of the birds laying eggs earlier and all of the plants having spring earlier across a continent, then we see we can detect anthropogenic signals,' said the study's lead author, Dr Cynthia Rosenzweig of Nasa's Goddard Institute for Space Studies.
'Humans are influencing climate through increasing greenhouse gas emissions,' she added.
'The warming world is causing impacts on physical and biological systems attributable at the global scale.'
The scientists also worked to rule out observed changes that could have been caused by factors other than human-related climate change.
Building on research done to support findings reported last year by the United Nations' Intergovernmental Panel on Climate Change (IPCC), Dr Rosenzweig and her co-authors brought together nearly 30,000 sets of data about biological and physical changes around the world.
They then matched those up with a detailed database of global temperature change and 'observed changes consistent with warming', said Dr Rosenzweig.
Critics of the earlier IPCC report had argued that the perceptible warming which has occurred over the last three decades is the result of natural causes, such as volcanic eruptions or changes in solar radiation.
But the new paper rejects such theories, saying that the changes in the Earth's natural systems cannot be explained by such factors.
Dr Rosenzweig said the link between human-caused global warming and observed biological and physical changes was just too strong.
On a global scale, the correlation is more than 99 per cent between the two factors, she said, while on a continental scale it is probably between 90 and 99 per cent. REUTERS, AGENCE FRANCE-PRESSE
Let's unite and do something now -->
http://evephua.blogspot.com/2008/04/lets-do-something-now.html