During the spring months, Arctic sea ice is sometimes called “dirty ice” referring to the brown colour that appears in the bottom section of the ice. As sea ice breaks up and shifts, so do the colonies of Nitzschia frigida that have been living within the ice. These visible dark spots are the remnants of the unique micro-communities that colonize the ice.
Food chain affect
Scientists are constantly examining how climate change is affecting the creation of Arctic sea ice. As temperatures rise, sea ice depletion increases. With this potential reduction in sea ice, scientists are now studying the affect this will have both on the diatom population as well as the larger Arctic food chain. Would a lack of sea ice see a reduction in the formation of Nitzschia frigida colonies and would this have an effect on the Arctic food web?
Where do they go when the ice disappears?
As Arctic waters open-up during the summer, Nitzschia frigida can be found floating in the water and sinking to the ocean bottom. How does the species get back into the ice?
Scientists are not certain why this occurs and a number of ideas have been proposed. One suggestion is that the newly formed ice in the water, near the bottom, captures microscopic cells including Nitzschia frigida. These ice crystals then rise to the surface and are incorporated into the newly forming sea-ice.