A COMPARISON OF PRECIPITATION SENSORS USED ON THE WET-ONLY COLLECTORS

The variability in performance of three precipitation sensor types, mo unted on three identical wet-only collectors, has been compared for ei ght months at a single site. The catch efficiencies, determined from t he sample volumes, are relatively high for these three apparatuses, si nce they exceed 89% on average. The recorded data of openings and clos ings of collector lids reveal that the highest losses of collection ef ficiency, observed for rainfalls of low intensity and low amount, are largely imputable to design and running characteristics of each sensor . Ionic compositions between the samples of these three collectors are relatively close, although significant differences are especially fou nd for H+, Ca2+, Mg2+ and K+, suggesting that these apparatuses are di fferently exposed to the dry deposition of soil particles. The RS 85 s ensor seems to be the most suitable one of the three, since it ensures a high catch efficiency for all rain types and tends to limit the exp osures of funnel to the dry deposition.