Leveloggers measure absolute pressure
(water pressure + atmospheric pressure) expressed in feet or centimeters
of water volume.
The most accurate method of obtaining
changes in water level is to compensate for atmospheric pressure using a
Barologger. This avoids any time lag in the compensation figures and any
errors introduced due to moisture buildup, kinking or damage to vented
cable. It can also be useful to have recorded barometric information to help
determine barometric lag and/or any damping effect from the surface to the
monitored aquifer.
The Barometric Compensation Wizard in the
Levelogger Windows software simplifies the adjustment of the level
measurements for barometric pressure changes, by using the synchronized
data from all Leveloggers on site and the site Barologger.
The overall results give more reliable,
highly accurate level data than that obtained when using high maintenance
and expensive vented cable.
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