che·​mo·​cline | \ ˈkē-mə-ˌklīn also ˈke- How to pronounce chemocline (audio) \
plural chemoclines

Definition of chemocline

: the boundary in a body of water that separates a fresh upper layer from a deeper layer containing higher concentrations of dissolved solids and gases The boundary, called the chemocline, between the deep water, rich with gas and minerals, and the fresh upper water stays intact. Gas saturates the bottom water and stays trapped there, like the carbon dioxide in a sealed bottle of seltzer.— Marguerite Holloway, New York Times, 27 Feb. 2001 This sulfide usually changes into a benign sulfate salt when the dissolved gas encounters oxygen to flourish at an underwater boundary called a chemocline.— N. Moreira, Science News, 28 May 2005

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First Known Use of chemocline

1937, in the meaning defined above

History and Etymology for chemocline

chemo- + -cline

Note: Term introduced by the British-born ecologist George Evelyn Hutchinson (1903-91; U.S. resident from the 1930’s) in “A Contribution to the Limnology of Arid Regions,” Transactions of the Connecticut Academy of Arts and Sciences, vol. 33 (1937), p. 74: “The zone of transition, where the rate of change of concentration with respect to depth is maximal, may be termed the chemocline.”

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The first known use of chemocline was in 1937

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chemo brain



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Cite this Entry

“Chemocline.” Dictionary, Merriam-Webster, Accessed 23 Jan. 2022.

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