‘Next year or the year after, the Arctic will be free of ice’

Scientist Peter Wadhams believes the summer ice cover at the north pole is about to disappear, triggering even more rapid global warming


Why should we be concerned about an Arctic that is free of ice in summer?

People tend to think of an ice-free Arctic in summer in terms of it merely being a symbol of global change. Things happen, they say. In fact, the impact will be profound and will effect the whole planet and its population. One key effect will be albedo feedback. Sea ice reflects about 50% of the solar radiation it receives back into space. By contrast, water reflects less than 10%. So if you replace ice with water, which is darker, much more solar heat will be absorbed by the ocean and the planet will heat up even more rapidly than it is doing at present.

Sea ice also acts as an air-conditioning system. Winds coming over the sea to land masses such as Siberia and Greenland will no longer be cooled as they pass over ice and these places will be heated even further. These effects could add 50% to the impact of global warming that is produced by rising carbon emissions.

What will be the effects of this accelerating increase in temperatures?

The air over Greenland will get warmer and more and more of its ice will melt. It is already losing about 300 cubic kilometres of ice a year. Antarctica is adding to the melt as well. Sea-level rises will accelerate as a result. The most recent prediction of the Intergovernmental Panel on Climate Change (IPCC) is that seas will rise by 60 to 90 centimetres this century. I think a rise of one to two metres is far more likely. Indeed, it is probably the best we can hope for.

That may not sound a lot but it is really very serious. It will increase enormously the frequency of storm surges all over the world. We may be able to raise the Thames barrier in Britain but in Bangladesh, it just means more and more people will be drowned.

Global warming is generally associated with increased fossil-fuel burning and consequent rises in levels of atmospheric carbon dioxide. But is that the only climate problem we face?

No it is not. We also have the issue of methane. Russian scientists who have investigated waters off their coast have detected more and more plumes of methane bubbling up from the seabed. The reason this is happening is closely connected with the warming of the planet and the shrinking of the Arctic icecaps.

How intense is methane as a heater of the atmosphere compared with carbon dioxide?

It is 23 times more powerful.


This Luxury Cruise Liner Is On The Front Lines Of Climate Change


This week, a massive, luxury cruise liner departed from Anchorage, Alaska, on the first leg of a 32-day cruise through the Northwest Passage.

The Crystal Serenity is carrying 1,070 passengers and 670 crew members. It has boutique shopping, a casino, a theater, and several bars on board. Its nine passenger decks tower over a hundred feet above the ocean surface. From these decks, passengers will see views that for centuries have been largely the provenance of intrepid explorers and a scant population of native people, clustered in hamlets that can be separated by hundreds of miles of Arctic tundra and icy waters.