Question

how is the sea level measured​

Answer 1

Answer:

using sounding line. A device made for it.

Answer 2

Answer:

NASA measures sea level around the globe using satellites. The Jason-3 satellite uses radio waves and other instruments to measure the height of the ocean's surface – also known as sea level. It does this for the entire Earth every 10 days, studying how global sea level is changing over time.Sea level is primarily measured using tide stations and satellite laser altimeters. Tide stations around the globe tell us what is happening at a local level—the height of the water as measured along the coast relative to a specific point on land.

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