The Economist Magazine has a special report this week on the warming of the Arctic Ocean.
The report is available at http://www.economist.com/node/21556798 and is highly informative. Originally Posted by The Economist "A heat map of the world, colour-coded for temperature change, shows the Arctic in sizzling maroon. Since 1951 it has warmed roughly twice as much as the global average. In that period the temperature in Greenland has gone up by 1.5°C, compared with around 0.7°C globally. This disparity is expected to continue. A 2°C increase in global temperatures—which appears inevitable as greenhouse-gas emissions soar—would mean Arctic warming of 3-6°C. Almost all Arctic glaciers have receded. The area of Arctic land covered by snow in early summer has shrunk by almost a fifth since 1966. But it is the Arctic Ocean that is most changed. In the 1970s, 80s and 90s the minimum extent of polar pack ice fell by around 8% per decade. Then, in 2007, the sea ice crashed, melting to a summer minimum of 4.3m sq km (1.7m square miles), close to half the average for the 1960s and 24% below the previous minimum, set in 2005. This left the north-west passage, a sea lane through Canada’s 36,000-island Arctic Archipelago, ice-free for the first time in memory. Scientists, scrambling to explain this, found that in 2007 every natural variation, including warm weather, clear skies and warm currents, had lined up to reinforce the seasonal melt. But last year there was no such remarkable coincidence: it was as normal as the Arctic gets these days. And the sea ice still shrank to almost the same extent. There is no serious doubt about the basic cause of the warming. It is, in the Arctic as everywhere, the result of an increase in heat-trapping atmospheric gases, mainly carbon dioxide released when fossil fuels are burned. Because the atmosphere is shedding less solar heat, it is warming—a physical effect predicted back in 1896 by Svante Arrhenius, a Swedish scientist. But why is the Arctic warming faster than other places?" more This excellent report prompted me to formulate the following idea. Geoengineering the climate can focus on cooling the Arctic Ocean in order to slow the ice melt and increase albedo, reflecting incoming solar radiation back to space. One potentially commercial method to achieve this goal is to float large sheets of reflective plastic just below the ocean surface, released from Norway into the Gulf Stream. The design would aim to optimise algae and fish growth, using wave energy to raise deep nutrient-rich water to the surface in 'Lovelock Tubes', and spreading this rich water across the surface sheet to mimic the upwelling of currents that are the source of the richest fisheries. This method would cool the surrounding water, reducing the heat input that is melting the sea ice. The systems would attract and feed fish with naturally produced algae, serving as efficient fish farms. They would float along the Gulf Stream as shown at Arctic Currents into the Barents Sea, where produced fish could be harvested. Small initial prototypes would identify design issues for potential scale up. The primary natural geoengineering impact would be entirely ecologically beneficial, cooling the Arctic Ocean to delay the risk of catastrophic warming. Robert Tulip -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
