The Arctic sea ice contains its own unique biodiversity with many endemic species. Specialized sympagic (ice-associated) communities live in brine pockets on top of the ice and in the ice-water interface. Flagellated protists, diatoms, and ice algae account for most of the primary productivity in the ice community. Protozoan and metazoan organisms (in particular turbellarians, nematodes, crustaceans, and rotifers), make up a portion of the ice community. Larvae and juveniles of some benthic animals migrate seasonally into the ice to feed on the algae in shallow waters. All of the organisms that live on and around the ice play a vital role in feeding the benthos. The climate cycle of melting and freezing causes these organisms to fall to the sea floor, creating food for the organisms living on the bottom.

The sediment record left by the sea ice can be used to reconstruct glacial/interglacial cycles. When sea ice and icebergs melt, they drop the ice rafted debris (IRD) that was contained within the ice as it scraped across the land and into the ocean. Sediment with abundant foraminifera and large sediment clasts is deposited during interglacial (interstadial) periods. Sediment that is mostly fine-grained, with few to no foraminifera, is deposited during glacial (stadial) periods. However, the lack of foraminifera in a sediment sample can also be a result of low surface salinity, a decrease in nutrients, dissolution of tests, a high sedimentation rate, or a thick layer of sea ice, causing difficulty in reconstructing glacial cycles.

The perennial sea ice is increasingly thinning, and there is a seasonal hole in the ozone layer over the North Pole. The thinning sea ice is having an effect on global albedo (amount of sunlight absorbed versus reflected back out of the Earth's atmosphere). Ice reflects more sunlight than it absorbs, so it has a cooling effect on the Earth. Without this ice to reflect the sun's rays, more heat will be absorbed, causing the Earth to warm. This causes a positive feedback that will continue to warm the earth, melting more sea ice. This is a concern because the added fresh water to the global marine system could cause a shutdown of the thermohaline circulation through the connection between the Arctic and Atlantic Oceans.

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