To stay alive, we have to meet a deadline.

If man does not stop burning fossil fuels, by the year 3000, rising oceans will drown many countries and cities, and temperatures will have risen by as much as 15 degree Centigrade.

Global warming could quadruple by 2100. Abrupt climate changes will become routine.

Ocean water will become less acidic, throwing the marine ecosystem out of gear and resulting in catastrophic results for the earth.

These are the findings of a study called Climate Change on the Millenial Timescale by the Tyndall Centre for Climate Change Research for the United Kingdom's Environment Agency.

And it's not just the British study - which is the first to examine the impacts of global warming beyond the end of this century -- that urges mankind to save itself right now.

Jim Hansen, a climate change scientist with America's National Aeronautics and Space Administration told the British newspaper The Independent: 'I think sea-level rise is going to be the big issue soon, more even than warming itself.'

The Tyndall Centre study says by 3000 oceans will rise by more than 11 metres if mankind ignore the peril the earth is in.

Hansen, director, NASA Goddard Institute for Space Studies in New York -- who is American President George W Bush's top climate modeller -- said the Bush administration tried to gag him when he wanted to speak to the media about new satellite data of the Greenland ice cap.

'They (the satellite data) show that Greenland seems to be losing at least 200 cubic kilometres of ice a year,' Hansen wrote in the as-told-to article in The Independent, adding that even two years ago, the ice cap was deemed to be stable.

The earth seems to be on the edge of a tipping point beyond which the melting ice would see huge armadas of icebergs floating in the ocean and drowning much of the earth, he wrote.

Both the British study and Hansen say the only way out is drastically cutting down carbon-based fuels and focusing on alternative energy sources. Now.

In fact, the British study says mankind must stop all greenhouse gas emissions - caused by burning fossil fuel -- by 2200.

And if we don't take action now, both Hansen and the study emphasise, the earth may set in motion disastrous consequences that we would not be able to reverse later, even if we tried.

Also see:

The Tyndall Centre's press release

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