Last week I wrote about the new Arctic nautical charts needed because of the melting of formerly (or soon-to-be-formerly) multi-year sea ice around Alaska. This week we have the latest estimate on how long we can expect to wait before some ships are regularly charging across the North Pole (in the summer anyway), from the Proceedings of the National Academy of Sciences.

Not long, it turns out: 2040.

ANALYSIS: Climate-Changed Coastlines Need New Maps

Researchers Laurence Smith and Scott Stephenson of the University of California at Los Angeles used seven climate models to project likely future sea ice losses and how it will change Arctic shipping from 2040 to 2059. The projections assumed a conservative (and very optimistic) medium-low increase in carbon emissions and therefore a medium-low rise in global warming.

The maps above graphically displays what they found. The quickest routes for ships to cross the Arctic Ocean by mid-century will likely be the Northwest Passage (diagonally, from middle left to lower right on the map) and over the North Pole (the bold red line across the upper part of the map). What’s called the Northern Sea Route is all those blue lines across the top of the map.

The red lines indicate the fastest available trans-Arctic routes for Polar Class 6 ships, which are moderate-capability icebreakers. Blue lines indicate the fastest available routes for common ships (dashed lines are national territorial boundaries). The white fuzziness indicates period-averaged sea ice concentration.

Freak Waves A Hazard on the High Seas

It’s worth noting that at mid-century, it will still require icebreakers to cross the North Pole in the summer. It would be interesting to project on to 2100 and see whether icebreakers will still be required.

Credit: Image courtesy of PNAS, DOI 10.1073/pnas.1214212110