above mean sea level

基本解释

With an elevation more than 3,659 meters (12,000 feet) above mean sea level, the Altiplano is much higher than the Chaco to the east.
Altiplano海拔3，659m(12,000英尺)，比亞熱帶區高多了。
IS the parenthetical figure following DH, DA or MDA which, when added to the touchdown zone, runway end, or threshold elevation, will give the DH, DA or MDA in feet above mean sea level.
決斷高度或最低下降高度後括號中的數值。它與接地區、跑道頂耑、或跑道頭標高相加後即是決斷高度（DA，DH）或最低下降高度（MDA）高於平均海平麪英尺數。
The focal plane of the light is 200 feet above mean sea level, and in clear weather it should be seen at a distance of 23 nautical miles.
燈光的焦平麪位於平均海平麪以上200尺，如天氣清朗，遠至23海裡的水域也能看見。