请问"海平面"怎么样译成英文啊

海平面:
1. sea level
2. sea-level
3. datum level
4. base level

mean sea level
平均海平面
sea level change
海平面变动
It's probable the sea surface will rise.
海平面可能会升高。
This land is on low sea level.
这块陆地在海平面下面。
atmospheric pressure at sea level is 1013 millibars.
海平面的气压是毫巴。
Equality of elevation above sea level.
等海拔高度海平面以上的高度相等
Fully one-fourth of Holland is below sealevel.
荷兰的整整四分之一在海平面下。
(heraldry) rising from the sea.
（纹章学）从海平面上升的。
Holland is a country which horizon is under the sea.
荷兰是一个地平线低于海平面的国家。
having a small elevation above the ground or horizon or sea level.
地面、地平线或者海平面以上较小的高度。

sea level

专业英语：sea level

sea leval.没错的。

sea level
n.
海平面

sea level
n.abbr:SL
The level of the ocean's surface, especially the level halfway between mean high and low tide, used as a standard in reckoning land elevatio