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WonderOcean circulation fact

The Antarctic Circumpolar Current flows uninterrupted around Antarctica, connecting the Atlantic, Pacific and Indian oceans while transporting heat, nutrients and carbon.

Antarctic Circumpolar Current

OceanClimateScience

The story behind the card

The current flows eastwards, pushed by strong westerly winds, and is the strongest current system in the world's oceans. Estimates of its flow range from about 135 to 175 sverdrups (one sverdrup is a million cubic metres of water per second), well over a hundred times the flow of all the world's rivers combined. It could form only after South America and Australia pulled away from Antarctica, opening the Drake Passage and the Tasmanian Seaway; many scientists date its start to about 34 million years ago, though the timing is debated. By keeping warmer water away from the continent, the current helped Antarctica's great ice sheets grow, and today it carries heat and carbon between the Atlantic, Pacific and Indian oceans.

Türkçe oku
Antarktika Çevresel Akıntısı, kıtanın çevresinde hiçbir karaya takılmadan döner. Atlas, Pasifik ve Hint okyanuslarını birbirine bağlar; ısı, besin ve karbon taşır.

Akıntı, güçlü batı rüzgârlarının itişiyle doğuya doğru akar ve dünya okyanuslarının en güçlü akıntı sistemidir. Taşıdığı su miktarı için yapılan tahminler 135 ile 175 sverdrup arasında değişir (bir sverdrup, saniyede bir milyon metreküp sudur); bu, dünyadaki bütün nehirlerin toplamının yüz katından fazladır. Akıntı ancak Güney Amerika ve Avustralya Antarktika'dan uzaklaşıp Drake Geçidi ile Tazmanya Geçidi açıldıktan sonra oluşabildi. Birçok bilim insanı başlangıcını yaklaşık 34 milyon yıl öncesine tarihler, ama bu tarih tartışmalıdır. Akıntı ılık suları kıtadan uzak tuttuğu için Antarktika'nın büyük buz örtülerinin büyümesine yardım etti. Bugün de Atlas, Pasifik ve Hint okyanusları arasında ısı ve karbon taşıyor.

Sources and further reading

Background reading: Antarctic Circumpolar Current
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