# Tag Info

15

Here is an estimate from Beauchamp and Baud (2002), for parts of the ocean around Pangea, for the latter parts of it's existence (~300-250mya). It is based on various previous papers that looked at deposits of carbonates and phosphate deposits, and made a few assumptions, including a sufficient supply of silica and nutrient inputs, and environments suitable ...

11

According to NOAA It takes almost a 1000 years to complete a cycle. I am not sure how accurate, or where the citation came from their information so take it with a grain of salt. 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 ...

11

The density of a water parcel evolves as it moves in the ocean. A parcel of bottom water (e.g., Antarctic Bottom Water (AABW) the densest water mass) is much denser than the surrounding water when it is formed near the surface (in the case of the AABW in polynyas and below the ice shelf in the Weddell and Ross Seas). As the parcel of AABW sinks, it flows ...

9

Salinity and temperature both affects the density of sea water. When water with a fixed salinity cools down, it becomes heavier and sinks. In the same way, when vapor or ice removes water from sea water, the remains is more saline and heavier. Thermohaline circulation can work as you describe. Surface water in the tropics is saline, due to evaporation, but ...

8

Warm water does hold more salt - at saturation, but seawater isn't even close to saturation. Surface sea water gets warm, starts to evaporate (hence clouds) and therefore gets denser. So it sinks to the ocean floor, where it cools down to about 4 deg Celsius, and gets denser still. But it still is a very long way from being saturated with salt, so 'how much ...

8

I wonder why Eckmann transport is not mentioned. You can have wind flowing parallely to the coastlines, for example, along a NS direction. Water driven by this wind will be subject to coriolis force and deflect sideways, and that will produce a net normal component of water movement to the wind direction. This is Ekmann transport, very simply stated. This ...

7

Some areas may well be relatively isolated. However water will come up when it is pushed from behind! E.g. there are strong sinks in the Norwegian Sea and Weddell Sea. This water must go somewhere and drives the deep water currents. These currents are pushed from behind and will come up when they hit a steep continental shelf. Such areas of upwelling water ...

7

Concerning the thermohaline circulation: the defining part of it, I think, is the formation of bottom water in the polar regions. The formation of Antarctic Bottom Water (AABW) in the Southern Ocean is strongly linked to the presence of the Antarctic Circumpolar current (ACC). The ACC was possible only after the opening of the Tasmanian Gateway and the ...

7

Downwelling speeds in the deep water formation areas are likely not significant when compared with the settling speeds of most sediment particles. While deep waters have clearly defined oxygen and nutrient characteristics, it does not seem likely that they can have a particular sedimentary character. The deep water circulation associated with the meridional ...

5

The diagram presented in the question is a very simplified version of the meridional overturning circulation. It is overly simplistic and generally creates very large misunderstandings. A good reference to the evolution of the Meridional Overturning Circulation diagrams is the work by Richardson (2008). Just in case you don't have access to Progress in ...

5

Upwelling of deep ocean water can be driven by the wind.

4

The short answer is 'yes'. Earth's response to climate change is closely coupled to the deep ocean's uptake of heat and $\ce{CO2}$; the ocean is by far the biggest sink for excess heat (~90% of the excess heat absorbed by the planet goes into the ocean, the rest largely goes towards melting ice sheets/glaciers). The ocean is also a major sink for carbon. ...

3

Usual salinity and solubility of NaCl An usual salinity in the world's major oceans is 35 g/kg. The solubility of sodium chloride in water is around 360 g/kg (Sodium Chloride, Solubility in water). Therefore, the solubility is not the limiting factor. Sea salt consists mainly of sodium chloride (NaCl). Therefore, this approximation should be OK. Mixing of ...

1

Yes.Thermohaline circulation is dependent on differences in water density, caused by differences in temperature and salinity between different bodies of water. It therefore requires deepwater areas, of which the northern and middle Atlantic have the most, for these differences or "gradients" to form. These are influences on the Gulf Stream. In addition, the ...

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