1. Inter-comparison of MAX-DOAS measurements of tropospheric HONO slant column densities and vertical profiles during the CINDI-2 campaign
- Author
-
European Space Agency, National Natural Science Foundation of China, Russian Foundation for Basic Research, Russian Academy of Sciences, National Aeronautics and Space Administration (US), National Science Foundation (US), European Commission, Max Planck Society, Wang, Y., Apituley, A., Bais, A., Beirle, S., Benavent, Nuria, Borovski, A., Bruchkouski, I., Lok Chan, K., Donner, Sebastian, Drosoglou, T., Finkenzeller, H., Friedrich, M.M., Frieß, Udo, García-Nieto, D., Gómez-Martín, L., Hilboll, A., Jin, J., Johnston, P., Koenig, T.K., Kreher, K., Kumar, V., Kyuberis, A., Lampel, J., Liu, C., Liu, H., Ma, J., Polyansky, O.L., Postylyakov, O., Querel, R., Saiz-Lopez, A., Schmitt, S., Tian, X., Tirpitz, J.L., Van Roozendael, M., Volkamer, R., Wang, Z., Xie, P., Xing, C., Xu, J., Yela, M., Zhang, C., Wagner, T., European Space Agency, National Natural Science Foundation of China, Russian Foundation for Basic Research, Russian Academy of Sciences, National Aeronautics and Space Administration (US), National Science Foundation (US), European Commission, Max Planck Society, Wang, Y., Apituley, A., Bais, A., Beirle, S., Benavent, Nuria, Borovski, A., Bruchkouski, I., Lok Chan, K., Donner, Sebastian, Drosoglou, T., Finkenzeller, H., Friedrich, M.M., Frieß, Udo, García-Nieto, D., Gómez-Martín, L., Hilboll, A., Jin, J., Johnston, P., Koenig, T.K., Kreher, K., Kumar, V., Kyuberis, A., Lampel, J., Liu, C., Liu, H., Ma, J., Polyansky, O.L., Postylyakov, O., Querel, R., Saiz-Lopez, A., Schmitt, S., Tian, X., Tirpitz, J.L., Van Roozendael, M., Volkamer, R., Wang, Z., Xie, P., Xing, C., Xu, J., Yela, M., Zhang, C., and Wagner, T.
- Abstract
We present the inter-comparison of delta slant column densities (SCDs) and vertical profiles of nitrous acid (HONO) derived from measurements of different multiaxis differential optical absorption spectroscopy (MAXDOAS) instruments and using different inversion algorithms during the Second Cabauw Inter-comparison campaign for Nitrogen Dioxide measuring Instruments (CINDI- 2) in September 2016 at Cabauw, the Netherlands (51.97° N, 4.93° E). The HONO vertical profiles, vertical column densities (VCDs), and near-surface volume mixing ratios are compared between different MAX-DOAS instruments and profile inversion algorithms for the first time. Systematic and random discrepancies of the HONO results are derived from the comparisons of all data sets against their median values. Systematic discrepancies of HONO delta SCDs are observed in the range of ±0:3×1015 molec. cm2, which is half of the typical random discrepancy of 0:6× 1015 molec. cm2. For a typical high HONO delta SCD of 2×1015 molec. cm2, the relative systematic and random discrepancies are about 15% and 30 %, respectively. The inter-comparison of HONO profiles shows that both systematic and random discrepancies of HONO VCDs and nearsurface volume mixing ratios (VMRs) are mostly in the range of ∼ ±0:5×1014 molec. cm2 and ∼ ±0:1 ppb (typically ∼ 20 %). Further we find that the discrepancies of the retrieved HONO profiles are dominated by discrepancies of the HONO delta SCDs. The profile retrievals only contribute to the discrepancies of the HONO profiles by ∼ 5 %. However, some data sets with substantially larger discrepancies than the typical values indicate that inappropriate implementations of profile inversion algorithms and configurations of radiative transfer models in the profile retrievals can also be an important uncertainty source. In addition, estimations of measurement uncertainties of HONO dSCDs, which can significantly impact profile retrievals using the optimal estimation method, need to consider n
- Published
- 2020