mean sea level

American  

[meen see lev-uhl] / ˈmin ˈsi ˈlɛv əl /

noun

1. Oceanography. the average height of the ocean's surface, as measured frequently and during all fluctuations of tides and atmospheric conditions over an extended time, usually a number of years.

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mean sea level British  

noun

1. (in the UK) the sea level used by the Ordnance Survey as a datum level, determined at Newlyn in Cornwall See sea level

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mean sea level Scientific  

1. See under sea level

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Example Sentences

Last year, the global mean sea level was around 11 centimetres higher than when satellite altimetry records began in 1993.

From Barron's • Mar. 23, 2026

In Redondo Beach, for instance, a near-shore tsunami could bring waves of up to 11 feet above mean sea level, compared to 9 feet possible coming from a distant earthquake.

From Los Angeles Times • Jun. 8, 2025

The Met Office said the mean sea level pressure reading for England and Wales in November is the lowest ever, breaking a record which had stood since 1916.

From Washington Times • Nov. 2, 2023

According to the World Meteorological Organization, global mean sea level rose by 4.5 millimeters per year between 2013 and 2022.

From Seattle Times • Apr. 17, 2023

Winds at 2,000 feet above mean sea level are shown in black; those at 4,000 feet, in white.

From A Quantitative Study of the Nocturnal Migration of Birds. Vol.3 No.2 by George H. Lowery.

Related Words

• water level