Arctic Ocean under change

Scoresby sound, Greenland

The Artic Ocean is rapidly changing due to global warming.

The extent of the summer ice cover is rapidly decreasing, and in 30 years most of the Arctic Ocean is predicted to be ice-free during summer. The rising air temperature has led to a later freeze-up in autumn, an earlier ice break-up in spring, and multi-year ice is frequently being replaced by first year ice. These changes alter the conditions for life adapted to the Arctic.

Primary production has increased due to reduced ice cover and increased irradiance, but not uniformly across the Arctic. A reduction registered in some areas is probably related to changes in nutrient mixing in the water column. The timing of algal blooms is changing, as is the community composition. It is not clear how these changes will affect higher trophic levels such as zooplankton and fish.