Barometric pressure, often referred to as atmospheric pressure, is a very unstable value affected by weather systems, seasonal changes and diurnal shifts. It is never a Static Value. The resulting shift in daily barometric values can be in excess of the equivalent of 30cm or 12” of water.
If you are monitoring water levels over a period of time, these barometric pressure changes will be reflected in your recorded measurements. If you do not remove these influencing pressure variations from your data you could falsely identify a draw on your water resources.
Heron Instruments barLog , our barometric logger, will remove these barometric influences from the data recorded by your Heron Instruments dipperLog data logger with a minimum of effort or fuss. Simply programme all the dipperLog you want to compensate with the same job number or project name as the one given to the barLog which will be used as the source of the compensating data.
It is recommended that for best results the barLog and dipperLog all be within the same 20km area and at the same altitude.
When it is time to download your data, simply download the barLog first. All subsequent downloads of dipperLog pressure data with the same job number or project name will be compensated by this barLog data. To determine whether your data has been compensated with barLog data, check the Compensation Flag in the data. If “1” this data has been compensated with data from an associated barLog, if “0” it hasn’t. If no barLog assigned, a constant value in the software will be used as the barometric pressure for compensation.
If you have a project that involves several different dipperLog in the same area, the use of a centrally located barLog ensures that all of the data you have collected is corrected with the same barometric pressure values. All dipperLog compensated must be at the same elevation as the barLog.