If you have less ice, the algae we are studying lose their habitat, but there is a whole community that lives in and around the sea ice. The underside is nursery and foraging area for zooplankton and fish, the ice above is hunting ground for polar bears.
Species have adapted to hide in and on the ice, something you can see in their pale coloration. Others have adapted to cling onto the ice-underside, which you can see in the morphology of their limbs or are adapted to the extreme salinity or temperatures that you find in the ice.
As a region, the Arctic is warming twice as fast as the global average. This is because its warming has multiple positive feedbacks that lead to even more warming – for instance, the loss of ice and therefore decrease in albedo, or the thawing of permafrost that can lead to wildfires and the release of greenhouse gases.
The consequences, however, are not restricted to the Arctic but affect the rest of our planet – for instance, through weakening of the jet stream that promotes extreme weather patterns in the northern hemisphere, through the melt of the Greenland Ice Sheet that leads to sea level rises and through enhanced greenhouse gas emission.