March 2, 2024

I, Science

The science magazine of Imperial College

A recent study suggests a unique solution to 're-stocking' arctic sea ice being destroyed by increasing global temperatures

With sea ice melt rates compounded by ever increasing temperature, it has been looking pretty gloomy for our planet. From 1979 to 2012 ice sheets have been losing mass at a rate of 3.5%–4.1% per decade and is predicted that the artic will be ice-free by 2030.

Not only does ice melt cause a rise in ocean levels and increase flooding, but it allows greater absorption of sunlight (and heat) into expanding oceans. This causes further warming and further melting in an endless positive feedback cycle. The delicate proportions of ice, snow and water that make up the arctic landscape are essential temperature regulators for the rest of the earth.

Since ice is a good reflective surface, directing the sun’s heat away from the earth, it’s a no brainer that we want to maintain as much of it as possible. But even if we were meeting our emission targets to prevent further warming (which we aren’t), this isn’t going to bring back the ice caps that have already melted into the oceans. So what can we do?

Scientists have devised a wild plan to freeze seawater to build back masses of lost ice in the arctic. The study, reported in Earth’s Future, proposes a scheme that could solve this ice-loss problem. The idea is to build around 10 million wind-pumps to spray water over the artic surface and replenish the icy mass.

It seems farfetched but the researchers have calculated how much ice thickness could be increased by pumping at different rates. They showed there is enough wind power in the arctic that a single 6m-diameter wind turbine can pump 1.3m of water over about 0.1km2 of arctic ice. Using a simple model showing how arctic ice freezes in winter, the scientists estimated the ice layer will increase by about 1m with this mechanism.

This is equivalent to increasing ice thickness at a rate approximately 17 times greater than the current average – a promising goal. With £40 billion each year, we could put devices over 10% of the arctic, which would then only take 10 years to reach the desired goals. The team also mentioned a pilot study in Canada, suggesting manually produced sea ice may have other benefits like extending polar bear and marine animal habitats.

The researchers concluded that, “Implementation over the entire Arctic in the early 2030s – in one year adding 1 metre of ice – would reset the clock to the present day, instead of the largely ice-free summer state one expects by the 2030”. Despite this, they added that to build a fleet of 10 million pumps, it would require roughly 10 million tons of steel per year. That’s a large proportion considering the world steel production amounts to 1,600 million tons of steel per year!

Although it is inspiring to see these kinds of wacky plans emerging, the project would most certainly be an economic ordeal. But who knows… maybe it is about time we did something a little crazy.

Amy Thomas is studying for an MSc in Science Communication

Banner Image: Arctic sea ice, Aleksandr Kutskii