A RAIN-GAUGE FOR THE MEASUREMENT OF FINESCALE TEMPORAL VARIATIONS

A rain gauge is described that quantizes rainwater collected by a funn el into equal-sized drops. Using a funnel of 150-mm diameter, the quan tization corresponds to 1/160 mm of rainfall, enabling the measurement of low rainfall rates and the attainment of a fine temporal resolutio n on the order of 15 s without unduly large sampling errors. Two drop- producing units are compared and an operational rain gauge design is p resented. Field comparisons with conventional rain gauges are made, sh owing excellent correlations for daily rain totals, and intercompariso ns between clusters of dropper gauges are also given. Examples of high ly resolved rainfall events are shown demonstrating the ability to mea sure low rainfall accumulations and also coherent high intensity event s of short duration, which are not detectable with conventional rain g auges.