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What is the difference between local sea level and global sea level?

11 May 2017, 4:44 pm

​This map shows trends in sea level, with arrows representing the direction and magnitude of change. Most people are surprised to learn that the surface of the ocean is not flat, and that the surface of the sea changes at different rates around the globe.

Global sea level trends and relative sea level trends are different measurements. Just as the surface of the Earth is not flat, the surface of the ocean is also not flat — in other words, the sea surface is not changing at the same rate at all points around the globe. Sea level rise at specific locations may be more or less than the global average due to many local factors: subsidence, ocean currents, variations in land height, and whether the land is still rebounding from the compressive weight of Ice Age glaciers.

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Original article: What is the difference between local sea level and global sea level?