The Importance Of Sea Ice In The Arctic Ocean

The Arctic Ocean is defined as the waters surrounding the North Pole, located within the Arctic Circle, including the northernmost islands of Canada, Norway, and Russia and is mostly covered by ice sheets, ice floes, icebergs and sea ice. Sea Ice is a thin, fragile layer of frozen ocean water that forms in the Arctic and Antarctic oceans. On average sea ice covers 20-25 km² of the Earth, accounting for 7% of the sea surface. The maximum extent of Sea Ice in the Arctic is recorded as 13-15x 10⁶km² with the minimum coverage being 7x10⁶km². Since Satellite monitoring in 1979, there has been a decline in the extent of Sea Ice during winter months, with the lowest coverage recorded in 2017 at 9.46 million square kilometers (NSIDC) leading many to conclude it is disappearing at a ‘devastating’ rate (Perovich et al 2002, Holland et al 2012, Liu et al 2012, Vihma 2014) (see Figure 1).

In later studies Stroeve observes a difference in sea ice formation, with it starting 3 days later and a melt season beginning 2 days earlier, per decade (Stroeve et al 2014). Estimates suggest that the Artic could be ice free sometime between 2030 (Liu et al 2012) and 2050 (Perovich et al 2002, Holland et al 2012, Vihma 2014). Cumulatively it is agreed that the decline of the Artic sea ice is globally significant as it controls the thermohaline circulation of the world’s oceans (Dima and Lohmann 2011). It keeps the poles cold by reflecting the suns heat back in a process known as "albedo” (Stroeve 2011), altering the Artic Oscillation and affecting weather regimes (Liu et al 2012), which supports a critical aspect of the global biosphere (Langbehn