A polynya (pronounced pol-in-YA) is an area of open water surrounded by sea ice. The term originates from the Russian term "полынья" for ice hole.
Some polynyas, such as the North Water Polynya in Canada, occur seasonally at the same time and place each year. Because animals can adapt their life strategies to this regularity, these types of polynyas are of special ecological research significance. In winter, marine mammals such as walruses, narwhals and belugas that do not migrate south, hang out there. In spring, the thin or absent ice cover allows light in, through the surface layer as soon as the winter night ends, which triggers the early blooming of microalgae that are at the basis of the marine food chain. So, polynyas are suspected to be places where intense and early production of the planktonic herbivores that ensure the transfer of solar energy (food chain) fixed by planktonic microalgae to Arctic cod, seals, whales, polar bear and man.
Links
International North Water Polynya Study (NOW) (http://www.fsg.ulaval.ca/giroq/now/)
Hence, recurring polynyas are suspected to be focal points for the intense and early production of the planktonic herbivores that ensure the transfer of solar energy fixed by planktonic microalgae to Arctic cod, seals, whales, polar bear and man (simplified Arctic food web).
In latent heat polynyas, the wind that carries the ice away also churns the water column, thus preventing the warming of the surface layer and the growth of algae which are entrained into deeper waters where darkness prevails.
In areas surrounding the polynya, the interval between the break-up of the ice cover in mid-summer and the return of the polar night may be as short as 2 months.
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