Leveling
Leveling turns up in 2 fields: tides, surveying. Here is what it means to the people in each one.
Leveling in tides
Precise measurement of height differences between bench marks and the gauge or staff using a level and rods.
Differential levelling with an optical or digital level and graduated rods, run between the tidal bench marks and the gauge's reference point or tide staff. It ties water level measurements to permanent marks so datums can be recovered and checked for movement. Runs are made at installation, at regular intervals and at removal, and each run is closed back on its start to measure the error.
"Leveling's due at the station this month, run all five marks plus the radar reference point."
Leveling in surveying
The process of measuring elevation differences between points on the earth's surface.
A fundamental surveying procedure used to determine the height of unknown points relative to a known datum. A surveyor uses an optical or digital level and a graduated staff to take successive backsights and foresights along a route. This creates a continuous chain of elevation transfers.
"We'll spend the morning leveling from the benchmark on the bridge down to the new sewer invert."