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

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 team linked algae growth, enhanced nitrogen fixation, and the upwelling of cool, nutrient-rich waters by studying coral cores collected across the Caribbean.

From Science Daily • Nov. 19, 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

Varying rainfall patterns and coastal upwelling both lead to more nutrient-dense waters, which only encourages algae growth.

From Los Angeles Times • Jul. 9, 2025

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

From "1491" by Charles C. Mann