sea level

American  

noun

1. the horizontal plane or level corresponding to the surface of the sea at mean level between high and low tide.

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sea level British  

noun

1. the level of the surface of the sea with respect to the land, taken to be the mean level between high and low tide, and used as a standard base for measuring heights and depths

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sea level Scientific  

1. The level of the ocean's surface. Sea level at a particular location changes regularly with the tides and irregularly due to conditions such as wind and currents. Other factors that contribute to such fluctuation include water temperature and salinity, air pressure, seasonal changes, the amount of stream runoff, and the amount of water that is stored as ice or snow.

2. ◆ The reference point used as a standard for determining terrestrial and atmospheric elevation or ocean depths is called the mean sea level and is calculated as the average of hourly tide levels measured by mechanical tide gauges over extended periods of time.

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Etymology

Origin of sea level

First recorded in 1800–10

Example Sentences

It will be an offence for any unmanned aircraft to fly below 2,000ft above sea level within one nautical mile of Edinburgh Castle.

From BBC

By better accounting for how heat inside the Earth interacts with ice above it, researchers can improve simulations of ice loss and refine estimates of Greenland's contribution to global sea level rise.

From Science Daily

By the weekend, it’s possible that there will be snow on the ground in areas as low as 5,000 feet above sea level by the weekend.

From Los Angeles Times

From there, smaller vehicles navigate over rough terrain before porters and mules haul baskets on the final stretch, up to 20,000 feet above sea level.

From The Wall Street Journal

A Swiss court has decided to hear a landmark climate case pitting residents of a tiny Indonesian island being swallowed by rising sea levels against cement giant Holcim, NGOs helping the islanders said Monday.

From Barron's

Related Words

• water level