Sea Level

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:

    Generation on generation, your neck rubbed the windowsill
    of the stall, smoothing the wood as the sea smooths glass.
    Donald Hall (b. 1928)

    Insurrection:... insurrection as soon as circumstances allow: insurrection, strenuous, ubiquitous: the insurrection of the masses: the holy war of the oppressed: the republic to make republicans: the people in action to initiate progress. Let the insurrection announce with its awful voice the decrees of God: let it clear and level the ground on which its own immortal structure shall be raised. Let it, like the Nile, flood all the country that it is destined to make fertile.
    Giuseppe Mazzini (1805–1872)