Arctic ice management. Issue 1 (24th January 2017) - Desch, Steven J.
Abstract: As the Earth's climate has changed, Arctic sea ice extent has decreased drastically. It is likely that the late‐summer Arctic will be ice‐free as soon as the 2030s. This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly. We show that where appropriate devices are employed, it is possible to increase ice thickness above natural levels, by about 1 m over the course of the winter. We examine the effects this has in the Arctic climate, concluding that deployment over 10% of the Arctic, especially where ice survival is marginal, could more than reverse current trends of ice loss in the Arctic, using existing industrial capacity. We propose that winter ice thickening by wind‐powered pumps be considered and assessed as part of a multipronged strategy for restoring sea ice and arresting the strongest feedbacks in the climate system. Key Points: To prevent strong positive feedbacks in the climate system, it may be necessary to artificially increase sea ice thickness in the Arctic We calculate that 1.4 m of seawater pumped to the surface freezes more readily and increases ice thickness by 1.0 m in one winter We describe a method employing devices using wind power to pump water and thicken ice, and discuss the feasibility and effectiveness of deploying such devices over the Arctic