Comparing precision lysimeter rainfall measurements against rain gauges in a coastal dune belt, Spain

Abstract

Precipitation measurements are performed mostly by simple automatic rain gauges installed at a certain level above the ground surface, but these methods are often affected by significant measurement errors due to the deformation of the wind field above the rain gauge orifice. In recent years precision lysimeters have emerged, providing an efficient means to improve rainfall measurements and to check the reliability of the standard devices. This article reports comparative rainfall measurements by different devices including a precision lysimeter, two tipping bucket rain gauges and one weighing rain gauge. Rainfall and meteorological data were collected within 3–4.5 years of operation using intervals of 1, 10 and 30 min for registration providing a large data set of exclusively rainfall precipitation without snow and without the effect of freezing. Results show very good agreement of lysimeter, tipping bucket 1 and the weighing pluviometer measurements without any need of precipitation correction, whereas tipping bucket 2 rain gauge underestimated precipitation.