WaterWatch has been calculating the actual evapotranspiration (= real water consumption) of the Netherlands for over a decade, which resulted in a time series from 1995 until present. The SEBAL algorithm calculates the actual evapotranspiration using satellite images and meteorological observations. Also the reference evapotranspiration is determined according to the international standard Penman-Monteith methodology. The precipitation surplus is the difference between the precipitation and the actual evapotranspiration.

The methodology for the reference evapotranspiration and the rainfall surplus is different  compared to the methodology used at the KNMI.

The information is weekly available on high resolution at www.mijnakker.nl.

Please contact Maurits Voogt (0317-427077, project leader MijnAkker) or Wim Bastiaanssen (0317 - 423401, developer of SEBAL) for more information on the country-wide evapotranspiration data.