Field Comparison of Tipping Bucket Raingauges

The rainfall data recorded by the Tipping Bucket Raingauge (TBRG) at six field sites were analysed to compare the recorded short duration rainfall with the Dines chart recorder and long duration rainfall with the standard gauge. The tests on the partial series from the short duration data showed that statistically the means and variances are the same for all durations except a few cases. The comparison of TBRG with the standard gauge showed a consistent over-recording (2-5 %) of rainfall by the TBRG over the standard gauge for all the sites except Hobart. For Hobart there was about 1.5 % underestimation and this might possibly be due to the relatively large number of days with light rainfall. The statistical tests showed that these differences are significant at the 5 % level. It can be concluded from the field experiment that the short time interval partial duration series from the TBRG and Dines instruments may be combined for analysis such as design intensity frequency- duration curves, but for daily and monthly climate analyses, data from the TBRG and standard gauge should not be combined.