Evaporation losses from containers of hellmann precipitation gauges

Abstract

The evaporation losses from the container of an old galvanized Hellmann gauge, 7·1 cm2aperture area, were five times greater than the losses from the container of a new gauge, 1·8 cm2aperture area, of almost the same grey colour. The maximum evaporation from the old gauge amounted to 0·75 mm per day. The same evaporation losses in the Baye of Montreux basin over a period of 10 years from April to September amounted to 0·09 mm per measurement or to 0·7 per cent of the precipitation catch. There is a relationship between the monthly percentage evaporation losses and the ratio of evaporation time and rainfall duration (r = 0·803). © 1974 Taylor & Francis Group, LLC.