upwelling
Quick Summary
A thermocline and a nutricline separate the warm, nutrient-deficient upper layer from the cool, enriched layer below. Under normal conditions (top), these interfaces are shallow enough that coastal winds can induce upwelling of the lower-layer nutrients to the surface, where they support an abundant ecosystem. During an El NiƱo event (bottom), the upper layer thickens so that the upwelled water contains fewer nutrients, thus contributing to a collapse of marine productivity.
Upwelling is the process where deeper, colder, nutrient-rich waters rise to the ocean's surface. This phenomenon is particularly significant in coastal areas, where winds and the Coriolis force drive surface waters away from the shore, allowing the nutrient-rich deeper water to ascend.1
These nutrient-rich waters fuel rapid phytoplankton growth, which in turn supports zooplankton and provides abundant food for larger marine life. Consequently, regions with strong upwelling, such as off the coasts of Peru and California, are often home to some of the world's most productive fisheries. Failures in upwelling can have devastating effects on marine ecosystems and the fisheries that depend on them. Changes in atmospheric circulation, like those during El NiƱo events, can influence the intensity and location of upwelling.2
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ocean currentā¦movements, often referred to as upwelling and downwelling, exhibit much lower speeds, amounting to only a few metres per month. As seawater is nearly incompressible, vertical movements are associated with regions of convergence and divergence in the horizontal flow patterns.
Read Moreā¦movements, often referred to as upwelling and downwelling, exhibit much lower speeds, amounting to only a few metres per month. As seawater is nearly incompressible, vertical movements are associated with regions of convergence and divergence in the horizontal flow patterns.
Read More- ocean currentEkman layer
ā¦in a process known as upwelling. Upwelling and downwelling also occur where the wind blows parallel to a coastline. The principal upwelling regions of the world are along the eastern boundary of the subtropical ocean waters, as, for example, the coastal region of Peru and northwestern Africa. Upwelling in theseā¦
Read Moreā¦in a process known as upwelling. Upwelling and downwelling also occur where the wind blows parallel to a coastline. The principal upwelling regions of the world are along the eastern boundary of the subtropical ocean waters, as, for example, the coastal region of Peru and northwestern Africa. Upwelling in theseā¦
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