Where is Antarctic Intermediate formed?

the Southern Ocean The Antarctic Intermediate Water is formed in the Southern Ocean and is characterized by a salinity minimum below the thermocline. It is found north of the Subantarctic Front.

How can you identify Antarctic Intermediate Water?

Antarctic Intermediate Water, ocean water mass found in all the southern oceans at depths of about 1,650 to 4,000 ft (500 to 1,200 m), characterized by temperatures of 37° to 45° F (3° to 7° C) and salinities of 33.8 to about 34.5 parts per thousand.

What causes formation of Antarctic Intermediate Water?

Formation. The formation of AAIW can be explained very simply through the Ekman transport process and the divergence and convergence of water masses. The winds over Antarctica are called the polar easterlies where winds blow from the east to the west.

Why might intermediate water forming in the Mediterranean Sea flow at the same depth as intermediate water formation in the Antarctic?

Mediterranean water is saltier than Atlantic water at the same depth so Med water sinks as it leaves the Med.

Where does the Mediterranean intermediate water form?

In the Atlantic, Mediterranean Intermediate Water (MIW) flows through the Straits of Gibraltar into the open ocean. This water is warm and salty from the warm temperatures and high evaporation characteristic of the Mediterranean Sea, so it is denser than the normal surface water and forms a layer about 1-1.5 km deep.

How is North Pacific intermediate water formed?

The North Pacific Intermediate Water is a well-defined salinity minimum, located in the North Pacific subtropical gyre. … NPIW forms when low-salinity, high-oxygen subpolar water is overrun by warm, saline subtropical waters. The NPIW occurs where the cold, low-saline Oyashio and warm, saline Kuroshio currents meet.

What makes Aaiw low salinity?

The AAIW, characterized by a salinity minimum (S < 34.3), has contributions from the coldest and densest (σ_θ ~ 27.3 kg/m³) member of the Southern Hemisphere Subpolar Mode Water or Subantarctic Mode Water (SAMW), which originates from deep winter convection along the Subantarctic Zone, and AAIW derived from the …

Which of these conditions describes the Antarctic Bottom Water?

Antarctic bottom water is an important water mass that forms on the Antarctic continental shelf as a cold, dense residual brine during the formation of sea ice. Its salinity of 34.62 parts per thousand and temperature of -1.9° C (28.6° F) result in a high…

What is the average speed of the ACC?

The Antarctic Circumpolar Current’s eastward flow is driven by strong westerly winds. The average wind speed between 40°S and 60°S is 15 to 24 knots with strongest winds typically between 45°S and 55°S.

Why is the movement of the Antarctic Bottom Water important?

The major significance of Antarctic bottom water is that it is the coldest bottom water, giving it a significant influence on the movement of the world’s oceans. Antarctic bottom water also has a high oxygen content relative to the rest of the oceans’ deep waters.

Where does deep water formation occur?

Deep water formation takes place in a few localised areas: the Greenland-Norwegian Sea, the Labrador Sea, the Mediteranean Sea, the Wedell Sea, the Ross Sea. Spreading of deep waters (e.g., North Atlantic Deep Water, NADW, and Antarctic Bottom Water, AABW), mainly as deep western boundary currents (DWBC).

Which water mass forms the deepest layer in the Atlantic Ocean?

North Atlantic Ocean 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]).

What process causes the Mediterranean intermediate water to become more dense than water in the adjacent Atlantic Ocean?

Mediterranean and Red Sea Intermediate Waters become more dense by significantly increasing salinity as surface water evaporates.

How long does thermohaline circulation take?

Lecture notes from one of Columbia University’s 2007 The Climate System class suggests this process takes between 100-1000 years. This paper says Thermohaline Circulation overturns deep water every 600 years or so.

Why does bottom water form in the Antarctic ocean but not in the Mediterranean sea?

Formation and circulation. Antarctic bottom water is created in part due to the major overturning of ocean water. Surface water is enriched in salt from sea ice formation. Due to its increased density, it flows down the Antarctic continental margin and continues north along the bottom.

Is the NADW well oxygenated?

These well-oxygenated bottom waters originate from down-welling/thermohaline circulation in polar regions. … Here North Atlantic Deep Water (NADW) is formed which feeds the upwelling in many other regions of the world ocean.

What water mass has the highest salinity?

That the Atlantic is the saltiest of the oceans is very clear with a branch to high salinity values at higher temperatures. The most voluminous water mass is the Pacific Deep Water that fills most of the Pacific below the intermediate waters at about 1000 m.

Which water mass has the highest density?

Water is densest at 3.98°C and is least dense at 0°C (freezing point). Water density changes with temperature and salinity. When water freezes at 0°C, a rigid open lattice (like a web) of hydrogen-bonded molecules is formed. It is this open structure that makes ice less dense than liquid water.

What is intermediate water mass?

2 Intermediate Waters. … AAIW is a global, Southern Hemisphere water mass characterized by a salinity minimum in the vertical at densities of σ_θ = 27.0–27.3 kg/m³ and at about 500–1000 m depth (Figure 14.13).

How is North Atlantic deep water formed?

Formation and sources. The NADW is a complex of several water masses formed by deep convection and also by overflow of dense water across the Greenland-Iceland-Scotland Ridge.

When did the Antarctic circumpolar current form?

The timing of the opening of the Drake Passage, between South America and the Antarctic Peninsula, is more disputed; tectonic and sediment evidence show that it could have been open as early as pre-34 Ma, estimates of the opening of the Drake passage are between 20 and 40 Ma.

Which ocean current drives the thermohaline circulation?

The cold, salty waters that drive the thermohaline circulation form in the Arctic Ocean, the North Atlantic, and the Southern Ocean. The shallow ocean floor along the Bering Straight prevents deep currents from flowing out of the Arctic Ocean into the Pacific.

Is Antarctic Bottom Water salty?

The Antarctic bottom water can be found at the very bottom of the ocean, directly overlaying the sea floor. This cold, salty, and therefore dense water spreads across the very deep, abyssal (greater than 3000 m) plains of the global ocean and can be found as far north as the equator.

What is one of the reasons why the Antarctic bottom water is so dense quizlet?

1) Antarctic bottom water is so dense because it forms off the southern coast of South America, where salt is concentrated in the ice, then squeezed out into the water, making a brine.

Which ocean water is coldest?

A “supercoolometer”, a device that sounds like it should be used to measure hipsters, has found the coldest seawater on Earth, under Antarctic sea ice.

Why is Antarctica colder than the Arctic?

Both the Arctic (North Pole) and the Antarctic (South Pole) are cold because they don’t get any direct sunlight. … The Antarctic is land surrounded by ocean. The ocean under the Arctic ice is cold, but still warmer than the ice! So the ocean warms the air a bit.

What is the strongest current in the ocean?

The Antarctic Circumpolar Current The Antarctic Circumpolar Current is the planet’s most powerful and arguably most important current. It is the only current to flow clear around the globe without being diverted by any landmass.

What is the most powerful ocean current the Gulf Stream?

The Gulf Stream is the fastest ocean current in the world with peak velocities near 2m/s. Shown to the left are velocity profiles across the Gulf Stream at the Straits of Florida and Cape Hatteras. In both sections the Gulf Stream is flowing into the page.