Sea Level
Mean sea level (MSL) is a measure of the average height of the ocean's surface (such as the halfway point between the mean high tide and the mean low tide); used as a standard in reckoning land elevation. MSL also plays an important role in aviation, where standard sea level pressure is used as the measurement datum of altitude at flight levels.
Read more about Sea Level: Measurement, Difficulties in Utilization, Sea Level and Dry Land, Recent Changes, Aviation
Famous quotes containing the words sea and/or level:
“The sea was wet as wet could be,
The sands were dry as dry.
You could not see a cloud, because
No cloud was in the sky:
No birds were flying overhead—
There were no birds to fly.”
—Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)
“To Time it never seems that he is brave
To set himself against the peaks of snow
To lay them level with the running wave,
Nor is he overjoyed when they lie low,
But only grave, contemplative and grave.”
—Robert Frost (1874–1963)