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WonderSea-ice ecology fact

In polar seas, strong winds or warmer water welling up from below can keep patches of sea open where thick ice would normally form. These areas of open water or thin ice are called polynyas.

Polynya

OceanClimateNatureScience

The story behind the card

The name comes from a Russian word for a patch of open water in ice. Polynyas matter to wildlife: seals, walruses, whales and seabirds use them to breathe and feed. As new ice keeps forming at their edges, it leaves its salt behind in very dense water, which sinks and helps drive deep ocean currents. The North Water, between Greenland and Canada's Ellesmere Island, is one of the Arctic's richest wildlife areas; the Inuit call it Pikialasorsuaq, 'the great upwelling'. Other polynyas are rare: the Weddell Sea polynya in Antarctica, seen by satellite in the mid-1970s, opened again briefly in 2016 and 2017, and scientists are still working out what triggers it.

Türkçe oku
Kutup denizlerinde sert rüzgârlar ya da derinden yükselen ılık su, normalde kalın buz tutması gereken yerlerde bazı alanları açık tutar. Açık su ya da ince buzla kaplı bu alanlara polinya denir.

Polinya adı, Rusçada buzun ortasındaki açık su için kullanılan bir sözcükten gelir. Bu alanlar yaban hayatı için çok değerlidir: foklar, morslar, balinalar ve deniz kuşları burada nefes alır ve beslenir. Kenarlarda durmadan oluşan yeni buz, tuzunu suya bırakır; iyice yoğunlaşan bu tuzlu su dibe çöker ve derin okyanus akıntılarını beslemeye yardım eder. Grönland ile Kanada'nın Ellesmere Adası arasındaki Kuzey Suyu, Kuzey Kutbu'nda yaban hayatının en zengin olduğu yerlerden biridir; İnuitler buraya “büyük yükselme” anlamına gelen Pikialasorsuaq der. Bazı polinyalar ise ender açılır: Antarktika'daki Weddell Denizi polinyası 1970'lerin ortasında uydudan görülmüş, 2016 ve 2017'de kısa süreliğine yeniden açılmıştı. Bilim insanları onu neyin tetiklediğini hâlâ araştırıyor.

Sources and further reading

Background reading: Polynya
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