Less oxygen and ice, more acid and heat. Jonathan Watts joins an expedition studying what this means for the planet
The demise of an entire ocean is almost too enormous to grasp, but as the expedition sails deeper into the Arctic, the colossal processes of breakdown are increasingly evident.
The first fragment of ice appears off the starboard bow a few miles before the 79th parallel in the Fram strait, which lies between Greenland and the Norwegian archipelago of Svalbard. The solitary floe is soon followed by another, then another, then clusters, then swarms, then entire fields of white crazy paving that stretch to the horizon.