There is more carbon dioxide in the atmosphere than for 55m years, enough to melt all the ice on the planet and submerge cities like London, New York and New Orleans, Sir David King, the government's chief scientific adviser has warned.
Speaking on his return from Moscow, where he has been acting as the prime minister's "unofficial envoy" to persuade the Russians to ratify the Kyoto protocol to fight climate change, Sir David said the most recent science bore out the worst predictions.
An ice core 3km deep from the Antarctic had a record of the climate for 800,000 years and showed the direct relationship between the amount of carbon dioxide in the atmosphere and warm and cold periods for the planet.
Critical in climate records is the quantity of ice at the poles and in glaciers. Records show that at the peak of the ice age 12,000 years ago, the sea was 150 metres below where it is now. "You might think it is not wise, since we are currently melting ice so fast, to have built our big cities on the edge of the sea where it is now obvious they cannot remain.
"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," he 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.
"I am sure that climate change is the biggest problem that civilisation has had to face in 5,000 years," he concluded.
Sir David, who is also to visit China and Japan, was speaking at the launch of a scientific expedition to Cape Farewell in the Arctic, which aims to raise awareness of climate change in students. It will also study the oceans' currents with the help of Southampton University, particularly the fate of the gulf stream which warms northern Europe but is slowing down because of excess fresh water in the north Atlantic caused by ice melt.
Dr King described how the ice caps like those on Mount Kilimanjaro, Tanzania, had been continuous for hundreds of thousands of years and survived through successive warm periods but were now expected to disappear in 30 to 40 years.
He said that the realisation of the scale of the crisis was what prompted him to say in January that climate change was a bigger threat than global terrorism. "We are moving from a warm period into the first hot period that man has ever experienced since he walked on the planet."
He said the heatwave of last summer in which 25,000 Europeans died had killed more people than terrorism, yet had not been given anything like the same level of attention.
The prime minister had charged him with talking to governments ahead of the G8 summit to convince them of the urgency of action on climate change, of research and development of renewables. He warned of the slow response of the climate system and said we were already doomed to 30 or 40 years of climate heating because of the carbon dioxide already in the atmosphere, hence the need to multiply effective flood defences such as the Thames barrier.
Sir David said because there was no ice on the planet 55m years ago, it was impossible to tell how much carbon dioxide there was in the atmosphere but it was probably only slightly more than "we are currently heading towards".
Sir David was backed up last night by Margaret Beckett, the environment secretary, speaking at the Green Alliance about the value of the EU's campaign to fight climate change.
"Climate change is the predominant global environmental issue where European leadership is vital," she said.
"But, of course, we need to persuade others to come with us, and we need to inject new momentum into international discussions on climate change.
"Above all, we also need to demonstrate that countries do not have to choose between their environmental and economic aspirations, to forfeit one or the other, but that these aspirations can not only be compatible but mutually reinforcing."
She said that the government had set ambitious targets for 2010 and beyond for virtually every big environmental issue.
But there needed to be a greater emphasis on assessing progress and identifying action needed to deliver existing commitments.
There also needed to be more consistent implementation of EU rules across the union, she said.
http://www.guardian.co.uk/print/0,3858,4970373-110970,00.html
