Analysis of parallel measurements of the automatic weather stations Valkenburg and Voorschoten in the Netherlands

This document describes the analysis of the parallel measurements between the two coastal automatic weather stations (AWS) Valkenburg (06210) and Voorschoten (06215) in the Netherlands. The airport station Valkenburg was relocated to Voorschoten on 16 July 2014 because the airport was given another destination. The airport is located at a distance of 4.2 km from the coast while AWS Voorschoten is located 2.2 km further inland. Besides differences in distance to the coast, their situation with respect surrounding urban areas differs. Both stations operated in parallel until 2 May 2016, when the measurements at AWS Valkenburg had to be terminated due to construction activities. The measurements of the period August 2014–April 2016 have been used for studying the climatological differences between the two sites. Despite the relatively small distance between the two stations, the results show statistically significant differences for most weather variables. For climatological applications, AWS Voorschoten can, therefore, not be considered as a continuation of AWS Valkenburg. Depending on the application, corrections can be made using the parallel measurements to obtain homogeneous time series.