Meteo data - daily quality controlled climate data KNMI, the Netherlands

KNMI operates automatic weather stations on land (incl. airports). These weather stations measures meteorological parameters such as temperature, precipitation, wind, air pressure and global radiation. On a daily basis all real-time collected observations and measurements (hourly) are validated on correctness and completeness. The validated data is archived in the Klimatologisch Informatie Systeem (KIS) of KNMI. The daily data is composed from hourly data and each day reference evaporation is calculated using the Makkink method. After the data has been processed and archived in KIS, changes are no longer possible. This assures data integrity.