From 1 - 3 / 3
  • We detect and quantify NOx point sources from the divergence of the horizontal NOx flux based on the continuity equation. The analysis steps are: - The NOx flux is determined for each TROPOMI (TROPOspheric Monitoring Instrument) orbit by upscaling the TROPOMI tropospheric NO2 column to NOx and multiplying it with horizontal wind fields from ECMWF (300m above ground). - The NOx fluxes are averaged for 2018-2019. - The divergence, i.e. spatial derivative, of the mean NOx flux is calculated, which is particularly sensitive for point sources. - NOx point sources are detected in the divergence map by an automated search algorithm for local maxima, and quantified by fitting a Gaussian function to these maxima. Ambiguous cases are skipped. TROPOMI is the satellite instrument on board of the Copernicus Sentinel-5 Precursor satellite. The approach of deriving emission information from the divergence of the NOx flux is described in Beirle et al., 2019: Beirle, S., Borger, C., Dörner, S., Li, A., Hu, Z., Liu, F., Wang, Y. and Wagner, T.: Pinpointing nitrogen oxide emissions from space, Science Advances, 5(11), eaax9800, doi:10.1126/sciadv.aax9800, 2019. The details and modifications made for the automated detection of NOx point sources on global scale are provided in Beirle et al., 2020: Beirle, S., Borger, C., Dörner, S., Eskes, H., Kumar, V., de Laat, A., and Wagner, T.: Catalog of NOx emissions from point sources as derived from the divergence of the NO2 flux for TROPOMI, to be submitted to Earth System Science Data, 2020.

  • This collection contains monthly mean tropospheric NO2 columns for Germany and surrounding areas derived from Sentinel-5P/TROPOMI Level-1B data. The Sentinel-5P tropospheric NO2 data is generated by DLR and provided in the framework of the mFUND-Project "S-VELD". The tropospheric NO2 data are vertical column densities with the unit "μmol/m2". Sentinel-5P observes Germany once per day at ~12:00 UTC and only cloud-free measurements (cloud fraction < ~0.2) are used. The Sentinel-5P tropospheric NO2 data within each month are averaged and gridded onto a regular UTM grid. The number of measurements used in the calculation of the averaged value are included in this collection as well.

  • This collection contains tropospheric NO2 columns for Germany and surrounding areas derived from Sentinel-5P/TROPOMI Level-1B data. The Sentinel-5P tropospheric NO2 data is generated by DLR and provided in the framework of the mFUND-Project "S-VELD". The tropospheric NO2 data are vertical column densities with the unit "µmol/m2". Sentinel-5P observes Germany once per day at ~12:00 UTC. These daily observations are gridded onto a regular UTM grid. The day and measurement time are included in the netCDF data file. Only tropospheric NO2 data for cloud-free Sentinel-5P measurements are provided (cloud fraction < ~0.2). Sentinel-5P cloud fraction data is included in this collection as well.

Barrierefreiheit | Datenschutz | Impressum