. Artificially whitening Arctic Ocean’s surface will reflect more Sun energy into space, and will restore some sea ice. However, it won’t cause significant cooling. Researchers from Lawrence Livermore National Laboratory and California Institute of Technology (all based in the United States) say that artificially whitening the Arctic will not prevent global climate change. Numerous studies suggest that global warming may cause Arctic frozen ground to melt and release large amounts of methane into the atmosphere. This could increase the world’s rising temperature. Scientists have suggested a variety of geoengineering strategies to mitigate these terrible climate impacts. One of these was artificially whitening the Arctic Ocean’s surface. Over a five-decade period, high-latitude air temperatures were simulated under various conditions. The current CO2 level is indicated by a solid black line. Pre-industrial CO2 levels are represented by a solid red line. A blue dashed area represents the alterations made to enhance sunlight reflection north of degN. A brown dashed area represents those alterations that increase sunlight reflection north of degN. Purple dashed lines represent alterations made to improve sunlight reflection between 70, 80degN. Image: Carnigie. Ivana Cvijanovic and Ken Caldeira set out to find the effects of Arctic Ocean Whitening. Their findings were published in Environmental Research Letters, an academic journal (citation below). There was no significant cooling. They found that although a large effort could, theoretically, bring back huge quantities of sea ice using this technique, significant cooling would be impossible. It would therefore not work effectively to keep the Arctic ground frozen. The lead author, Dr. Cvijanovic (previously Carnegie), stated that the Arctic Ocean will be ice-free for a portion of the year by the middle of this century. The authors warn that this could cause significant ecological problems in Arctic including habitat changes and loss biodiversity. Dr. Cvijanovic said: “But the problem isn’t only local. A number of studies have shown that Arctic sea-ice loss can impact weather patterns across most of North America and much of Asia.” The possibility of bleaching the Arctic Ocean remains under discussion. Some proposals include floating microbubbles and grains which would decrease the Sun’s radiation. Researchers point out that it is more important to assess whether such a proposal could be implemented. To study the effects of Arctic whitening on a planet that has four times as much atmospheric CO2 and an Arctic that’s around (18degCdegF (warmer), Dr. Cvijanovic used special model configurations. It is effective in the restoration of much of the ocean ice. When they fed these data to their Arctic whitening models, it found that there was an approximate three quarter of a square km of sea ice per whitened square mile. Ocean whitening will have only a modest cooling effect and won’t do much to preserve permafrost, the thick layer of soil below freezing, or prevent methane from being released. The findings suggested that sea whitening and recovery could have an impact on climates far beyond the Arctic. US weather could change, Dr. Cvijanovic said. “Ocean bleaching and sea ice recovery could result in wetter, milder, and more stable winters in the southwest United States.” However, scientists suggested that such a whitening technique might work on a smaller scale than in an entire ocean, perhaps in a bay or estuary. Citation: “Impacts on Arctic sea-ice restoration and Northern Hemisphere weather,” Ivana Cijanovic, Ken Caldeira, and Douglas G MacMartin. Enviromental Research Letters. Published 28 April 2015. DOI: 10.1088/1748-9326/10/4/044020. Carnegie Video – September Sea Ice Animation of scientists’ findings.
The Arctic Ocean may be whitened to stop sea-ice melting, but not climate changes
