MAX-DOAS measurements of atmospheric rural and urban NO2 gradients during the TROLIX'19 campaign
- 1BK Scientific GmbH, Mainz, Germany (karin.kreher@bkscientific.eu)
- 2Virginia Polytechnic Institute and State University, Blacksburg, USA
- 3Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
- 4Aristotle University of Thessaloniki, Thessaloniki, Greece
- 5Max Planck Institute for Chemistry, Mainz, Germany
- 6Royal Belgian Institute for Space Aeronomy (IASB-BIRA), Brussels, Belgium
- 7TNO, Petten, The Netherlands
- 8National Institute of Water & Atmospheric Research (NIWA), Lauder, New Zealand
- 9National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
As part of the TROLIX'19 (TROpomi vaLIdation eXperiment) campaign (2 September to 4 October 2019), measurements of tropospheric NO2 columns and surface concentrations were made using the MAX-DOAS (Multi-AXis Differential Optical Absorption Spectroscopy) technique. To characterise any TROPOMI sub pixel (less than 3.5 km x 7 km) heterogeneity, four MAX-DOAS instruments were deployed at rural locations close to Cabauw (51.97°N, 4.93°E) and further six instruments were operated within the highly industrialized area of Rotterdam (51.92°N, 4.48°E) in the Netherlands. All instruments performed sky scanning from the horizon (from approximately 1°) to the zenith. In addition, two of the MAX-DOAS instruments (Pandoras) also measured total NO2 columns in direct sun mode.
Here we present first results focusing on the measurements of NO2 spatial gradients made at sites within approximately 3-10 km distance in a rural and an urban environment. The data analysis was done in two steps. Differential slant column densities were calculated using the data processing procedures established during the CINDI-2 intercomparison campaign (Kreher et al., in review, 2019) in UV and VIS spectral ranges. Tropospheric columns, near surface concentrations and profiles were then calculated using the Pandora real time algorithm as well as the NDACC UV-Vis Central Processing system developed in the ESA FRM4DOAS project. Local heterogeneity at the surface level was evaluated using in-situ NO2 measurements available from several routine monitoring stations within the area of interest. The local NO2 heterogeneity effect on TROPOMI validation is also discussed.
Reference:
Kreher, K. et al.: Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV-Visible spectrometers during the CINDI-2 campaign, Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-157, in review, 2019.
How to cite: Kreher, K., Spinei, E., Piters, A., Apituley, A., Bais, A., Doerner, S., Fayt, C., Friedrich, M., Frumau, A., Hendrick, F., Hermans, C., Karagkiozidis, D., Querel, R., Van Roozendael, M., Vonk, J., and Wagner, T.: MAX-DOAS measurements of atmospheric rural and urban NO2 gradients during the TROLIX'19 campaign, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20796, https://doi.org/10.5194/egusphere-egu2020-20796, 2020.