Global Warming Affects life

Sci. & Tech.
Wildlife and environment already hit by climate change

GUARDIAN NEWS SERVICE

By Ian Sample

Global warming is disrupting wildlife and the environment on every continent, according to an unprecedented study that reveals the extent to which climate change is already affecting the world's ecosystems.

Scientists examined published reports dating back to 1970 and found that at least 90% of environmental damage and disruption around the world could be explained by rising temperatures driven by human activity.

Big falls in Antarctic penguin populations, fewer fish in African lakes, shifts in American river flows and earlier flowering and bird migrations inEurope are all likely to be driven by global warming, the study found.

The team of experts, including members of the UN's intergovernmental panel on climate change (IPCC) from America, Europe, Australia and China, is the first to formally link some of the most dramatic changes to the world's wildlife and habitats with human-induced climate change.

In the study, which appears in the journal Nature, researchers analysed reports highlighting changes in populations or behaviour of 28,800 animal and plant species. They examined a further 829 reports that focused on different environmental effects, including surging rivers, retreating glaciers and shifting forests, across the seven continents.

To work out how much - or if at all - global warming played a role, the scientists next checked historical records to see what impact natural variations in local climate, deforestation and changes in land use might have on the ecosystems and species that live there.

In 90% of cases the shifts in wildlife behaviour and populations could only be explained by global warming, while 95% of environmental changes, such as melting permafrost, retreating glaciers and changes in river flows were consistent with rising temperatures.

"When we look at all these impacts together, it is clear they are across continents and endemic. We're getting a sense that climate change is already changing the way the world works," said lead author Cynthia Rosenzweig, head of the climate impacts group at Nasa's Goddard Institute for Space Studies in New York.

Most of the reports examined by the team were published between 1970 and 2004, during which time global average temperatures rose by around 0.6C. The latest report from the IPCC suggests the world is likely to warm between 2C and 6C by the end of the century.