The Arctic isn’t what it once was.
Temperatures there are rising at twice the global average rate, huge wildfires are sweeping through vast tracts of Canadian forest, and mysterious holes are appearing in Siberian permafrost. Throughout 2014, a recurring kink in the jet stream—possibly rooted in declining Arctic sea ice—has helped to alternately bake the West and chill out the East by disturbing the typically stable polar vortex.
Now, there’s a new side effect of the Arctic becoming increasingly ice-free: big waves.
The house-sized waves measured by oceanographer Jim Thomson and his research team during a Beaufort Sea storm in 2012 are bigger than any seen before in that part of the Arctic, where it’s warmer now than at any point since humans began living there 44,000 or so years ago. Previously, there was just too much ice for waves to form.
The waves aren’t just a symptom of the Arctic’s ice woes, though. They may accelerate the problems. According to research published earlier this year by Thomson and a colleague (PDF), the waves may be a mechanism for accelerating ice retreat, which in turn may cause even bigger waves. The result, according to Thomson, is “a potentially new process”: a vicious cycle that is expected to ultimately end in an ice-free summertime Arctic within decades.
The science here is fairly simple. Less ice means more open water, and when combined with the Arctic’s sometimes strong winds, that water can more easily churn itself into bigger waves. It seems that’s exactly what the new research has found.
Thomson and his team were in the Arctic again this week, deploying a new suite of solar-powered robotic oceanographers. The sensors are designed to measure the interaction between waves and the edge of the sea ice pack in advance of this year’s annual ice breakup and eventual nadir in September. Thomson says the data gathered this summer should provide “a quantum leap” in terms of measurements of Arctic waves.
I reached Thomson by email while he was off the coast of Prudhoe Bay, Alaska, on his research vessel in the Arctic Ocean, and he told me:
It’s been a great week. We’ve deployed everything for the big collaborative project this summer, and all the gear is working (no small trick for autonomous systems at sea). Now, with a few days left, we are making some more detailed measurements near the ice edge. We started this yesterday and the data are excellent, by which I mean a very clean signal of wave filtering by the ice and changes in the turbulence levels near the water surface. Our goal these last few days is to collect similar data over a wider parameter range.
Freelance journalist Mark Harris was also aboard and produced an amazing series of tweets chronicling the efforts:
Besides being yet another hazard to the steadily increasing flow of ships navigating the icy waters, bigger waves may help speed coastal erosion. And, oh yeah, there’s that whole thing about there not being any ice left at all. Thomson’s latest research paper has a stark conclusion regarding future ice-free summers: “This would be a remarkable departure from historical conditions in the Arctic, with potentially wide-ranging implications for the air-water-ice system and the humans attempting to operate there.”