Calibration of tipping bucket rain gauges

A tipping bucket rain gauge measures rain fall volumes with high resolution, thus enabling calculation of rain intensities. To ensure that the volume of one tipping is independent of the rain intensity a syphon is introduced. However, the syphon introduces problems with respect to both a time lag and problems when reconstructing the underlying rain intensities. This problem is studied in detail. The rain gauge in question is a RIMCO tipping bucket rain gauge, used by the Danish Water Pollution Control Committee (DWPCQ. The rain gauge has been tested in the laboratory and in the field. The study shows, that it is possible to reduce the syphon volume to a level where the problems of the syphon are small and yet maintain the same accuracy with respect to volume registrations.