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

See Examples For:

upwelling

The warm water, the result of change in currents and stalling of the typical cold water upwelling that occurred along the coast, was nutrient-poor and led to steep crashes in phytoplankton and anchovy populations.

From Los Angeles Times ● Jul. 29, 2026

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

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

However, based on the data available, fire pollution appears to have influenced the ocean’s chemistry far less than this year’s upwelling effect did.

From Los Angeles Times ● Sep. 17, 2025

The upwelling, known as the Humboldt Current, chills the air above it.

From "1491" by Charles C. Mann