North Atlantic Deep Water

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North Atlantic Deep Water

oceanography

Also known as: NADW

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June 17, 2026

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North Atlantic Deep Water (NADW) is a significant component of the thermohaline circulation in the Atlantic Ocean. This deep ocean current is formed primarily in the Greenland and Norwegian seas when salty surface water cools, becomes denser, and sinks. This process, known as convection, causes the water to flow southward along the western edge of the Atlantic. Additional NADW is formed in the Labrador Sea and from the outflow of the Mediterranean Sea, which increases its salinity.

The NADW plays a crucial role in regulating global heat distribution and influencing climate patterns. It ventilates the Atlantic Ocean and eventually spreads into the Indian and Pacific oceans. The sinking of NADW is balanced by the slow upwelling of deep water, mainly in the Southern Ocean, which replenishes the upper water layers.12

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Arctic Ocean
Oceanography
This produces North Atlantic Deep Water (NADW), which circulates in the world ocean. An increase in this freshwater and ice export could shut down the thermocline convection in the GIN Sea; alternatively, a decrease in ice export might allow for convection and ventilation in the Arctic Ocean…
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This produces North Atlantic Deep Water (NADW), which circulates in the world ocean. An increase in this freshwater and ice export could shut down the thermocline convection in the GIN Sea; alternatively, a decrease in ice export might allow for convection and ventilation in the Arctic Ocean…
Read More

ocean current
Thermohaline circulation
…types contribute to the so-called North Atlantic Deep Water(NADW), which is the cooler, sinking portion of the AMOC that flows southward in the Atlantic. Each one of them differs, though they share a common attribute of being relatively warm (greater than 2 °C) and salty (greater than 34.9 parts per…
Read More
…types contribute to the so-called North Atlantic Deep Water(NADW), which is the cooler, sinking portion of the AMOC that flows southward in the Atlantic. Each one of them differs, though they share a common attribute of being relatively warm (greater than 2 °C) and salty (greater than 34.9 parts per…
Read More

Indian Ocean
Deep (thermohaline) circulation
…and 3,000 metres) is the North Atlantic Deep Water (named for the source of that current), and below 10,000 feet is Antarctic Bottom Water from the Weddell Sea. Those cold, dense layers creep slowly northward from their source in the Antarctic Circumpolar Region, becoming nearly anoxic (oxygen-deficient) en route. Unlike…
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…and 3,000 metres) is the North Atlantic Deep Water (named for the source of that current), and below 10,000 feet is Antarctic Bottom Water from the Weddell Sea. Those cold, dense layers creep slowly northward from their source in the Antarctic Circumpolar Region, becoming nearly anoxic (oxygen-deficient) en route. Unlike…
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climate
The Gulf Stream
…Ocean; the other is the North Atlantic Deep Water, which has a temperature of 2.2 to 3.5 °C (4 to 6.3 °F) and a salinity between 34.90 and 34.97 ppt and which occupies the deepest layers of the ocean (generally below 1,000 metres [about 3,300 feet]). The North Atlantic Central…
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…Ocean; the other is the North Atlantic Deep Water, which has a temperature of 2.2 to 3.5 °C (4 to 6.3 °F) and a salinity between 34.90 and 34.97 ppt and which occupies the deepest layers of the ocean (generally below 1,000 metres [about 3,300 feet]). The North Atlantic Central…
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paleoceanography
…resulted in the formation of North Atlantic Deep Water, which began flowing south along the continental rise of North America at this time. Sediments redistributed and deposited by this deep current are called contourites and have been extensively studied by American geologists Bruce Heezen, Charles D. Hollister, and Brian E.…
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…resulted in the formation of North Atlantic Deep Water, which began flowing south along the continental rise of North America at this time. Sediments redistributed and deposited by this deep current are called contourites and have been extensively studied by American geologists Bruce Heezen, Charles D. Hollister, and Brian E.…
Read More