The diversity of life on, in and under the sea ice

Dr Hauke Flores, marine biologist at the Alfred Wegener Institute.


Arctic Ocean

Life in the Polar Sea

The sea-ice regions of the Arctic and Antarctic are among the most rapidly changing habitats on Earth. The cause of these rapid changes is climate change, which is causing a rapid decline in sea-ice cover, particularly in the Arctic. Because sea ice itself performs a central function in polar ecosystems, significant impacts are expected on the ecosystem functions and -services polar communities provide. These include, for example, the uptake and sequestration of carbon from the atmosphere or the production of large quantities of krill and fish.

Unfortunately, changes in the polar regions are proceeding faster than our understanding of sea-ice ecosystems. Sea ice plays a critical role in the life cycle of polar key species in both hemispheres. The best-known examples are Arctic cod (Polar cod) and Antarctic krill. The microalgae (ice algae) living in sea ice contribute significantly to the food supply of polar communities. They not only serve as food for species used by humans, such as fish and krill, but also indirectly feed polar bears and penguins.

For this reason, at AWI we research the biodiversity of sea ice-associated fauna and their role in the functioning of polar ecosystems, elemental cycles and fish stocks. The interactions between sea ice, its inhabitants and many beneficiaries, as well as their functions and services, are so far poorly quantified and hardly represented in regional and global models. A sound understanding of the ecological importance of sea-ice communities is necessary to assess the impacts of climate change on polar ecosystems, protected wildlife, and biological resources, and to develop targeted conservation measures.