What does blend and update mean?
The series collected from participating countries generally do not contain data for the most recent years. This is partly due to the time that is needed for data quality control and archiving at the home institutions of the participants, and partly the result of the efforts required to include the data in the ECA database. To make available for each location a time series that is as complete as possible, we have included an automated update procedure that relies on the daily data from SYNOP messages that are distributed in near real time over the Global Telecommunication System (GTS). In this procedure the gaps in a daily series are also infilled with observations from nearby stations, provided that they are within 25km distance and that height differences are less than 50m. Blending is default for the data that are accessed in netCDF through DODS. The other download options under daily data allow to select Blend and update = Yes or No. In case a blended series is chosen, information o
