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Melting the Arctic Ice Cap |
This material presents the plan of Petr Mikhailovich Borisov for melting the Arctic ice cap. If the Arctic ice is once melted much less of the sun's radiation will be reflected out into space and therefore the arctic ice cap will not re-form. An ice-free Arctic Ocean would be a great boon to oceanic shipping, especially between Europe and East Asia. Much land in northern Canada and Siberia would be freed of permafrost and made suitable for agriculture. Borisov believed that an ice-free Arctic Ocean would lead to increased evaporation of water and hence increased rainfall worldwide, including the region of Sahara Desert leading to grass growing there. Borisov considers all of the impacts of the melting of the Arctic ice cap to be beneficial. He asserts that the melting of the Greenland ice cap would raise sea levels at a rate of only 1.5 to 2 mm per year.
Soviet climatologists in the 1950's and 60's gave considerable thought to how the melting of the Arctic ice cap could be achieved. Two conferences were held on the topic in Leningrad in the early 1960's after an initial conference was convened in Moscow by the Presidium of the USSR Academy of Sciences in 1959 on the topic.
The idea of melting the Arctic ice cap goes back at to 1877 when Harvard geologist Nathaniel Shaler proposed channeling more of the warm Kuroshio Current through the Bering Strait. Carroll Livingston Riker in 1912 proposed using a 200 mile jetty off Newfoundland to divert more of the Gulf Stream to the Arctic Basin. Julian Huxley while he was head of UNESCO proposed, in 1946, to use nuclear weapons to break up the Arctic ice cap. Borisov in his article lists the more recently suggested methods for melting the Arctic ice cap.
The last method listed above entails creating a dam across the Bering Strait. Such a dam would be 74 kilometers in width. It would have to go down to a depth of no more than 58 meters. This dam is within the range of technical feasibility.
The purpose of the dam is to allow the pumping of cold Arctic water into the Pacific. At present the flow of warm Atlantic waters is counterbalanced by a flow of cold Arctic waters into the Atlantic. Under Borisov's proposal about 145,000 km³ of cold Arctic water would be pumped through through the dam into the Pacific thus drawing more warm Atlantic water into the Arctic Basin. After a period of about three years that increased Atlantic flow will reach the Bering Strait area. According to Borisov the amount of heat brought to the Arctic Basin would increase from the present level of 472×1015 kcal/year to 1370×1015, a three fold increase. Also Borisov estimates that the reduced albedo of Earth as a result of the melting of the ice and snow will reduce the radiation loss due to reflection from 54 kcal/cm²year to 10. He estimates that the process would raise the temperature of the Arctic water by an amount in the range of 1.9° C to 8.2° C.
Borisov proposed that the dam be built in sections of about 250 meters. These section would be prefabricated of freeze resistance ferro-concrete in convenient shipyards and floated to the construction site. They would be anchored to the sea bottom by means of pilings. He further suggests that the top of the dam be shaped so that ice floes would ride up over the dam and break off on the southern side.
Borisov asserts that some of the energy required for the construction of the dam and the operation of the pumps would come cost-free. The increased rainfall due to the ice-free Arctic would, according to Borisov, lead to higher rates of production at existing hydroelectric plants.
Borisov's article is an interesting illustration of how different the thinking of climatologists of thirty five years ago was compared with today. In the first decade of the twenty first century climatologists are predicting that in a few decades the arctic ice cap will melt due to general global warming.
Source:
P.M. Borisov, "Can we Control the Arctic Climate?", Bulletin of the Atomic Scientists,
March, 1969, pp. 43-48.
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