Ground based in situ observations of nitrogen_dioxide at Schmücke (DE0008R) using NaJ_solution. These measurements are gathered as a part of the following projects sel_GEOmon2.1, EMEP and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: nitrogen_dioxide in air (mass_concentration_of_nitrogen_dioxide_expressed_as_nitrogen_in_air)