What is an upwell?

What is an upwell?

intransitive verb. : to well up specifically : to move or flow upward.

How does downwelling occur?

Downwelling occurs when the water on the surface of the sea becomes denser than the water beneath it and so it sinks. Most downwelling happens at the poles. There, cold air chills the water.

What are two reasons water moves down in the North Sea?

The ocean conveyor gets its “start” in the Norwegian Sea, where warm water from the Gulf Stream heats the atmosphere in the cold northern latitudes. This loss of heat to the atmosphere makes the water cooler and denser, causing it to sink to the bottom of the ocean.

Why is there a high level of nutrients in deeper waters?

In the high latitude ocean, surface water is cold and therefore the vertical density gradient is weak, which allows for vertical mixing of water to depths much greater than the sunlit “euphotic zone” as a result, the nutrient supply is greater than the phytoplankton can consume, given the available light (and iron, see …

What can cause an increase in the density of ocean water?

There are two main factors that make ocean water more or less dense than about 1027 kg/m3: the temperature of the water and the salinity of the water. Ocean water gets more dense as temperature goes down. So, the colder the water, the more dense it is. Increasing salinity also increases the density of sea water.

Which part of the ocean has the most nutrients?

You can see the highest abundance close to the coastlines where nutrients from the land are fed in by rivers. The other location where chlorophyll levels are high is in upwelling zones where nutrients are brought to the surface ocean from depth by the upwelling process.

Why are oxygen levels highest at the surface of the ocean?

Typical oceanic dissolved oxygen profiles are shown in Figure 5.4. 1. Oxygen content is highest at the surface for two main reasons; this is where oxygen dissolves into the ocean from the atmosphere, and the surface water is where oxygen is produced by phytoplankton through photosynthesis .