This was one of the worst summers ever for Arctic sea ice, and the worst ever seen if you focus on the Asian side of the Arctic Ocean. Not only is the Northern Sea Route open for shipping between Europe and East Asia, but for the first time, cargo ships could reasonably cross the Arctic Ocean north of all the Asian islands. That shipping route has been more or less open (icebreaker escort recommended, just in case) since the beginning of August and could stay open through October. About 400 or maybe 500 cargo ships are expected to cross the Arctic Ocean this summer, the most ever.
With every year that goes by there is less reason to hope that the ice will ever make a comeback. In all, three fourths of the Arctic sea ice volume at its April peak melted away this summer, similar to the last seven years. If you think of the way weather naturally varies from one year to the next, a complete Arctic melt-out is almost within the range of normal weather fluctuations. Arctic ice melt is enhanced by a mild winter, a warm or stormy spring, a persistent straight-line wind pattern in almost any direction, and the list goes on and on. From normal weather variation alone we can expect an Arctic melt-out within the next 30 years, if the warming trend doesn’t catch up with it sooner than that. This summer provides a hint of what that will be like. All you have to do is imagine that this summer’s extraordinary melt on the Asian side of the ocean spread across to Greenland and Canada. Or, imagine the summer breezes arriving one month early. If three months of summer weather melt about 75 percent of the ice, four months would melt about 100 percent. That’s how close to the edge the Arctic is at this point.
According to the ice statistics, it was a near-normal melt in the Canadian Arctic, but it was enough to open the Northwest Passage for explorer and science ships. That’s another sign of how much the Arctic has changed. A Northwest Passage opening, previously something that happened once every few decades, has become something you can almost plan on in any September you choose. It wasn’t a cargo-ship year in the Northwest Passage, but that may come soon enough — the last remnants of the Canadian ice shelves melted away this summer after drifting south during the spring.