On-line detection of errors in tipping-bucket raingauges

Tipping-bucket raingauges can produce misleading reports as a consequence of a number of factors. Very fast tips may result from gauge disturbance, faulty bucket positioning or abrupt snow melt. Very slow tips may result from partial blockage. An absence of tips is an indication of a major problem. This paper suggests easily programmable diagnostic checks that may be used to identify any of these problems, using either the data from a single gauge, or by using additional information from neighbouring gauges. The checks were motivated by the need to process 2 years of data from Bolton in the northwest of England. The checks are then tested on archived data from the HYREX experiment, finding 90% of confirmed faults.