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:
“All the morning we had heard the sea roar on the eastern shore, which was several miles distant.... It was a very inspiriting sound to walk by, filling the whole air, that of the sea dashing against the land, heard several miles inland. Instead of having a dog to growl before your door, to have an Atlantic Ocean to growl for a whole Cape!”
—Henry David Thoreau (1817–1862)
“If there is a price to pay for the privilege of spending the early years of child rearing in the driver’s seat, it is our reluctance, our inability, to tolerate being demoted to the backseat. Spurred by our success in programming our children during the preschool years, we may find it difficult to forgo in later states the level of control that once afforded us so much satisfaction.”
—Melinda M. Marshall (20th century)