upwelling

American  

[uhp-wel-ing] / ʌpˈwɛl ɪŋ /

noun

1. an act or instance of welling up.

   an upwelling of public support; an upwelling of emotion in his voice.

2. Oceanography. the process by which warm, less-dense surface water is drawn away from along a shore by offshore currents and replaced by cold, denser water brought up from the subsurface.

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upwelling Scientific  

/ ŭp-wĕl′ĭng /

1. The rising of cold, usually nutrient-rich waters from the ocean depths to the warmer, sunlit zone at the surface. Upwelling usually occurs in the subtropics along the western continental coasts, where prevailing trade winds drive the surface water away from shore, drawing deeper water upward to take its place. Because of the abundance of krill and other nutrients in the colder waters, these regions are rich feeding grounds for a variety of marine and avian species. Upwelling can also occur in the middle of oceans where cyclonic circulation is relatively permanent or where southern trade winds cross the Equator.

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Etymology

Origin of upwelling

First recorded in 1850–55; upwell + -ing ¹

Example Sentences

Other major upwelling systems include the Humboldt Current off Peru and the Benguela and Canary Currents along the west coast of Africa.

From Science Daily • Nov. 30, 2025

In a recent publication in Nature Geoscience, the researchers describe how strong wind-driven upwelling near the equator brings phosphorus-rich deep water to the surface and transports it northward into the Caribbean.

From Science Daily • Nov. 19, 2025

The researchers describe a process in which phosphorus delivered by upwelling deep water and nitrogen supplied by nitrogen-fixing bacteria together fuel the blooms seen over past decades.

From Science Daily • Nov. 19, 2025

“The coastal upwelling has been really notable right outside the San Francisco Bay and west of Point Reyes,” Mehle said.

From Los Angeles Times • Jul. 26, 2025

It is always a queer shock, part a sudden upwelling of grief, part unaccountable amazement.

From "The Lives of a Cell" by Lewis Thomas