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 whole sea become an entanglement of watery bodies
lost to the world bearing what they cannot hold. Broken,
beaten, desolate, reaching from the dead to be taken up
they cry out, failing, failing! their cries rising
in waves still as the skillful yachts pass over.”
—William Carlos Williams (18831963)
“The truth is, that common-sense, or thought as it first emerges above the level of the narrowly practical, is deeply imbued with that bad logical quality to which the epithet metaphysical is commonly applied; and nothing can clear it up but a severe course of logic.”
—Charles Sanders Peirce (18391914)