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)
“Young children learn in a different manner from that of older children and adults, yet we can teach them many things if we adapt our materials and mode of instruction to their level of ability. But we miseducate young children when we assume that their learning abilities are comparable to those of older children and that they can be taught with materials and with the same instructional procedures appropriate to school-age children.”
—David Elkind (20th century)