25,000 people on one continent as a result of a man-made activity.
What was it?
The answer is the heatwave of 2003, brought on by excess greenhouse gases.
Guardian Unlimited | Special reports | Melting ice: the threat to London’s future:
On current trends, cities like London, New York and New Orleans will be among the first to go.
“Ice melting is a relatively slow process but is speeding up. When the Greenland ice cap goes, the sea level will rise six to seven metres, when Antarctica melts it will be another 110 metres,” [Sir David King] said.
Records of the 3km deep Antarctic ice core showed that during ice ages the carbon dioxide in the atmosphere was around 200 parts per million (ppm), and during warm periods reached around 270 ppm, before sinking back down again for another ice age. That pattern had been repeated many times in that period but had now been broken because of the intervention of man.
Carbon dioxide in the atmosphere had reached 360 ppm in the 1990s and now was up to 379 ppm and increasing at the rate of 3 ppm a year – reaching a level not seen for 55m years when there was no ice on the planet because the atmosphere was too warm.
Imagine waterfront cities — surely you can name a dozen — being evacuated, abandoned, by rising water. It seems to me there are a few national capitals threatened by this.
I’ve often wondered why the skeptics have a hard time seeing this as a possibility, let alone a problem: what they seem to forget is that life continues on this planet. We have examples living in the Antarctic ice, others living in the superheated steam vents of the Mid-Atlantic Ridge or the geysers of Yellowstone. The life form that is at risk is ours. Humans require a pretty narrow climatic range for survival. There are too many of us to migrate to what will be the temperate regions of the future, and the resulting die-off might doom everyone by rendering the air and water unsafe.