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

Their findings show that upwelling zones experience acidification rates that exceed those "expected" from atmospheric CO2 alone.

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

“But those increases are completely dwarfed by the major shift that happened in the ocean between the end of February and the beginning of April — the upwelling event.”

From Los Angeles Times • Sep. 17, 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

Taisin listened as Sister Ailan gave her instructions on what she would need to do when she reached Cathair, but beneath it all she felt an upwelling of emotions that threatened to engulf her.

From "Huntress" by Malinda Lo