measurements, instruments, references
2006-07-04 20:46:25 · 3 answers · asked by tank 1 in Science & Mathematics ➔ Earth Sciences & Geology
They take the average between high tide and low tide.
2006-07-04 21:16:34 · answer #1 · answered by nicole 3 · 0⤊ 0⤋
Well.........there are many different oceans, which all have different depths but theoretically speaking sea level would be the same around the world just for the simple fact gravity would have the same effect on the water no matter where it is besides high and low tide that is. So in conclusion sea level is the level at which the sea touches land and that's where the measurement starts. I think they factor in the curvature of the earth for places not bordering the sea measure that way. That's what i think
2006-07-04 20:59:14 · answer #2 · answered by cherrijo79 1 · 0⤊ 0⤋
A Ruler.
2006-07-04 20:51:56 · answer #3 · answered by alex 2 · 0⤊ 0⤋