11 Feb 2021

11 Feb 2021

Review status: this preprint is currently under review for the journal AMT.

Evaluation of the coupled high-resolution atmospheric chemistry model system MECO(n) using in situ and MAX-DOAS NO2 measurements

Vinod Kumar1, Julia Remmers1, Steffen Beirle1, Joachim Fallmann2, Astrid Kerkweg3, Jos Lelieveld1, Mariano Mertens4, Andrea Pozzer1, Benedikt Steil1, and Thomas Wagner1 Vinod Kumar et al.
  • 1Max Planck Institute for Chemistry, Mainz, Germany
  • 2Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Germany
  • 3Institute of Energy and Climate Research 8, Troposphere, Forschungszentrum Jülich, Jülich, Germany
  • 4Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany

Abstract. We present high spatial resolution (up to 2.2 × 2.2 km2 simulations focussed over south-west Germany using the online coupled regional atmospheric chemistry model system MECO(n). Numerical simulation of nitrogen dioxide (NO2) surface volume mixing ratios (VMR) are compared to in situ measurements from a network with 193 locations including background, traffic-adjacent and industrial stations to investigate the model's performance in simulating the spatial and temporal variability of short-lived chemical species. We show that the use of a high-resolution and up-to-date emission inventory is crucial for reproducing the spatial variability, and resulted in good agreement with the measured VMRs at the background and industrial locations with an overall bias of less than 10 %. We introduce a computationally efficient approach that simulates diurnal and daily variability in monthly resolved anthropogenic emissions to resolve the temporal variability of NO2.

MAX-DOAS measurements performed at Mainz (49.99° N, 8.23° E) were used to evaluate the simulated tropospheric vertical column densities (VCD) of NO2. We propose a consistent and robust approach to evaluate the vertical distribution of NO2 in the boundary layer by comparing the individual differential slant column densities (dSCDs) at various elevation angles. This approach considers details of the spatial heterogeneity and sensitivity volume of the MAX-DOAS measurements while comparing the measured and simulated dSCDs. The effects of clouds on the agreement between MAX-DOAS measurements and simulations have also been investigated. For low elevation angles ≤ 8°), small biases in the range of −14 to +7 % and Pearson correlation coefficients in the range of 0.5 to 0.8 were achieved for different azimuth directions in the cloud-free cases indicating good model performance in the layers close to the surface. Accounting for diurnal and daily variability in the monthly resolved anthropogenic emissions was found to be crucial for the accurate representation of time series of measured NO2 VMR and dSCDs and is particularly critical when the atmospheric lifetime of NO2 is relatively long.

Vinod Kumar et al.

Status: open (until 10 May 2021)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on amt-2021-23', Anonymous Referee #1, 04 May 2021 reply
  • RC2: 'Review Kumar et al.', Anonymous Referee #2, 04 May 2021 reply

Vinod Kumar et al.

Vinod Kumar et al.


Total article views: 361 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
266 88 7 361 1 1
  • HTML: 266
  • PDF: 88
  • XML: 7
  • Total: 361
  • BibTeX: 1
  • EndNote: 1
Views and downloads (calculated since 11 Feb 2021)
Cumulative views and downloads (calculated since 11 Feb 2021)

Viewed (geographical distribution)

Total article views: 326 (including HTML, PDF, and XML) Thereof 326 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 08 May 2021
Short summary
We present high resolution regional atmospheric chemistry model simulations focused around Germany. We highlight the importance of spatial resolution of the model itself as well as the input emissions inventory and short scale temporal variability of emissions for simulations. We propose a consistent approach for evaluating the simulated vertical distribution of NO2 using MAX-DOAS measurements while also considering its spatial sensitivity volume and change in sensitivity within this volume.