How are you at treading water?

From the Guardian:

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.
...
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.