Global warming is approaching the critical point of no return, after which widespread drought, crop failure and rising sea-levels would be irreversible, an international climate change task force warned Monday.
According to the report, urgent action is needed to stop the global average temperature rising by 2 degrees Celsius above the level in 1750 — the approximate start of the Industrial Revolution when mankind first started significantly polluting the atmosphere with carbon dioxide.
Beyond a 2 degrees rise, “the risks to human societies and ecosystems grow significantly” the report said, adding there would be a risk of “abrupt, accelerated, or runaway climate change.”
It warned of “climatic tipping points” such as the Greenland and West Antarctic ice sheets melting and the Gulf Stream shutting down.
No accurate temperature readings were available for 1750, the report said, but since 1860, global average temperature had risen by 0.8 percent to 15 degrees Celsius.
The two degrees rise could be avoided by keeping the concentration of carbon dioxide in the atmosphere below 400 parts per million (ppm). Current concentrations of 379 ppm “are likely to rise above 400 ppm in coming decades and could rise far higher under a business-as-usual scenario,” the report warned.
Read CNN’s coverage: CNN.com - Report: Global warming approaching critical point - Jan 24, 2005
Download the report itself here
