Air Mass Origin in the Lower Stratosphere using HALO Measurements and CLaMS Simulations (AMOS)
Final Report Abstract
Our project AMOS demonstrates that the transport of air masses out of the Asian monsoon anticyclone into the lower northern extratropical stratosphere is an important driver during summer and fall and is determined by different processes and time scales. The basic transport mechanisms were analysed using simulations with the chemical Lagrangian transport model (CLaMS) combined with airborne measurements with the German aircraft HALO (High Altitude and Long Range Research Aircraft) in the northern Hemisphere as well as with balloon measurements in Asia. The transport of tropospheric trace gases (e.g., H2O, aerosols and their chemical precursors or ozone-depleting substances such as short-lived halogen-containing trace gases) by the Asian monsoon anticyclone into the lower stratosphere changes the chemical composition in this part of the Earth’s atmosphere. Further, radiatively active species transported into the lower extratropical stratosphere have a significant impact on surface climate and can cause regional radiative forcing. In our project AMOS we show that short-lived anthropogenic substances such as PAN, bromine-containing as well as chlorine-containing trace gases in addition to long-lived tracers (e.g. CH4, H2O, CO, N2O, SF6) are transported from sources in Asia via the Asian monsoon anticyclone into the northern extratropical lower stratosphere. In particular the impact of chlorine-containing very short lived-substances that are not regulated by the Montreal Protocol (regulating the production and use of substances that deplete the Earth’s Ozone Layer) and its amendments and adjustments on stratospheric ozone depletion is an important and ongoing investigation. On the one hand increasing anthropogenic emissions in the future are expected due to the strong growth of Asian economies; on the other hand the implementation of new emission control measures (in particular in China) has reduced the anthropogenic emissions of some pollutants transported into the lower stratosphere. It needs to be monitored in the future whether the transport of anthropogenic emissions of ozone-depleting and radiatively active substances into the lower stratosphere will further increase, which will likely impact the surface climate. Second, in the project AMOS it is demonstrated that in addition to the Asian and American summer monsoon systems also transport of tropospheric air by tropical cyclones (typhoons, hurricanes) have an impact on the chemical composition of the northern extratropial lower stratosphere. This transport pathway is in particular important for natural emissions from sea surfaces such as bromine-containing substances that have an impact ozone chemistry. In summary, the project AMOS contributes to the deduction of the source regions of pollutants at the Earth’s surface and their transport pathways to the UTLS, which is important to develop recommendations for regulations of anthropogenic surface emissions. The project is an important contribution to future reports to assess the risks of emissions of ozone-depleting substances and radiatively active substances into the atmosphere e.g. by the World Meteorological Organisation (WMO).
Publications
- Water vapor increase in the lower stratosphere of the Northern Hemisphere due to the Asian monsoon anticyclone observed during the TACTS/ESMVal campaigns, Atmos. Chem. Phys., 18, 2973-2983
Rolf, C., Vogel, B., Hoor, P., Afchine, A., Günther, G., Krämer, M., Müller, R., Müller, S., Spelten, N., and Riese, M.
(See online at https://doi.org /10.5194/acp-18-2973-2018) - Lagrangian simulations of the transport of young air masses to the top of the Asian monsoon anticyclone and into the tropical pipe, Atmos. Chem. Phys., 19, 6007-6034
Vogel, B., Müller, R., Günther, G., Spang, R., Hanumanthu, S., Li, D., Riese, M., and Stiller, G. P.
(See online at https://doi.org/10.5194/acp-19-6007-2019) - 3-D tomographic observations of Rossby wave breaking over the Northern Atlantic during the WISE aircraft campaign in 2017, Atmos. Chem. Phys. Discuss., 2020, 1-30
Krasauskas, L., Ungermann, J., Preusse, P., Friedl-Vallon, F., Zahn, A., Ziereis, H., Rolf, C., Plöger, F., Konopka, P., Vogel, B., and Riese, M.
(See online at https://doi.org/10.5194/acp-21-10249-2021) - Airborne in situ measurements of short-lived chlorocarbons and investigation of their pathways from northern hemispheric source regions into the lowermost stratosphere, Dissertation, Universität Wuppertal, 2020
Valentin Michael Lauther
(See online at https://doi.org/10.25926/kqvq-hb36) - Strong day-to-day variability of the Asian Tropopause Aerosol Layer (ATAL) in August 2016 at the Himalayan foothills, Atmos. Chem. Phys., 20, 14 273-14 302
Hanumanthu, S., Vogel, B., Müller, R., Brunamonti, S., Fadnavis, S., Li, D., Ölsner, P., Naja, M., Singh, B. B., Kumar, K. R., Sonbawne, S., Jauhiainen, H., Vömel, H., Luo, B., Jorge, T., Wienhold, F. G., Dirkson, R., and Peter, T.
(See online at https://doi.org/10.5194/acp-20-14273-2020) - Examining transport in the Upper Troposphere - Lower Stratosphere with the infrared limb imager GLORIA, Dissertation, Universität Wuppertal, 2021
Lukas Krasauskas
- Organic and inorganic bromine measurements around the extratropical tropopause and lowermost stratosphere: Insights into the transport pathways and total bromine, Atmospheric Chemistry and Physics Discussions, 2021, 1-53
Rotermund, M. K., Bense, V., Chipperfield, M. P., Engel, A., Grooß, J.-U., Hoor, P., Hüneke, T., Keber, T., Kluge, F., Schreiner, B., Schuck, T., Vogel, B., Zahn, A., and Pfeilsticker, K.
(See online at https://doi.org/10.5194/acp-2021-202) - Pollution trace gases C2 H6 , C2 H2 , HCOOH, and PAN in the North Atlantic UTLS: observations and simulations, Atmos. Chem. Phys., 21, 8213–8232
Wetzel, G., Friedl-Vallon, F., Glatthor, N., Grooß, J.-U., Gulde, T., Höpfner, M., Johansson, S., Khosrawi, F., Kirner, O., Kleinert, A., Kretschmer, E., Maucher, G., Nordmeyer, H., Oelhaf, H., Orphal, J., Piesch, C., Sinnhuber, B.-M., Ungermann, J., and Vogel, B.
(See online at https://doi.org/10.5194/acp-21-8213-2021) - Trajectory Analysis on the Asian Tropopause Aerosol Layer (ATAL) based on Balloon Measurements at the Foothills of the Himalayas, Dissertation, Universität Wuppertal, 2021
Sreeharsha Hanumanthu
(See online at https://doi.org/10.25926/nwh7-3j35)
