Project A04:
Sources and processes controlling aerosol composition in the UTLS – From tropical monsoon to extratropical regions

Brief Summary

The objective of this proposal is to study aerosol chemical composition and dynamics in the UTLS region from tropical monsoon to extratropical regions by using aircraft-based in-situ mass-spectrometric measurements. This includes conducting a detailed analysis of particle composition data from previous and upcoming tropical missions with the research aircraft HALO, HIAPER, and Geophysica as well as studying small-scale aerosol dynamics in the extratropical UTLS. The main research topics are the role of vertical transport of both precursor gases and particles from the boundary layer into the UTLS, and the processes that lead to further transport into the stratosphere, either by large-scale upward motion in the tropics or by small-scale mixing processes at the extratropical tropopause.
The tropical datasets include data from the missions ACRIDICON-CHUVA (2014), EMeRGe (2018), CAFE-Africa (2018), StratoClim (2017), as well as from the upcoming missions ACCLIP and CAFE-Brazil, both currently scheduled for 2021. During these campaigns, we operated/will operate four different aerosol mass spectrometers, including the novel hybrid mass spectrometer ERICA, covering particles with diameters between 60 nm and roughly 3 μm. For studying extratropical small-scale aerosol gradients in the UTLS and aerosol cross-tropopause exchange, a dedicated aircraft campaign is planned by this collaborative research center (CRC) using the German research aircraft Learjet that is equipped with a tow shuttle (AIRTOSS). We will operate two fast sizing instruments (UHSAS), one in the cabin and one in the AIRTOSS as well as the compact aerosol mass spectrometer CARIBIC-AMS in the cabin. The CARIBIC-AMS has been operated in the IAGOS-CARIBIC container between October 2018 and March 2020 and is currently scheduled to continue its regular UTLS measurements in late 2021. These data are also available for studying the aerosol composition in the extratropical tropopause region. In the network of the CRC, the ambient chemical composition data will be complemented by laboratory studies on upper tropospheric secondary organic aerosol formation, including organic sulfates and -nitrates. Collaboration with the modelling groups of the CRC will enhance our understanding of the implications of particle transport into the UTLS, particle formation in the UTLS, the role of aged aerosol particles for cloud formation, and cross-tropopause exchange of particles for the radiative balance of the UTLS region.

Members

Publications

Joppe, P., J. Schneider, K. Kaiser, H. Fischer, P. Hoor, D. Kunkel, H.-C. Lachnitt, A. Marsing, L. Röder, H. Schlager, L. Tomsche, C. Voigt, A. Zahn, and S. Borrmann (2024): The influence of extratropical cross- tropopause mixing on the correlation between ozone and sulfate aerosol in the lowermost stratosphere. Atmospheric Chemistry and Physics 24 (13), 7499–7522. doi: 10.5194/acp-24-7499-20

Wendisch, M., S. Crewell, A. Ehrlich, A. Herber, B. Kirbus, C. Lüpkes, M. Mech, S. J. Abel, E. F. Akansu, F. Ament, C. Aubry, S. Becker, S. Borrmann, H. Bozem, M. Brückner, H.-C. Clemen, S. Dahlke, G. Dekoutsidis, J. Delanoë, E. De La Torre Castro, H. Dorff, R. Dupuy, O. Eppers, F. Ewald, G. George, I. V. Gorodetskaya, S. Grawe, S. Groß, J. Hartmann, S. Henning, L. Hirsch, E. Jäkel, P. Joppe, O. Jourdan, Z. Jurányi, M. Karalis, M. Kellermann, M. Klingebiel, M. Lonardi, J. Lucke, A. Luebke, M. Maahn, N. Maherndl, M. Maturilli, B. Mayer, J. Mayer, S. Mertes, J. Michaelis, M. Michalkov, G. Mioche, M. Moser, H. Müller, R. Neggers, D. Ori, D. Paul, F. Paulus, C. Pilz, F. Pithan, M. Pöhlker, V. Pörtge, M. Ringel, N. Risse, G. C. Roberts, S. Rosenburg, J. Röttenbacher, J. Rückert, M. Schäfer, J. Schäfer, V. Schemannn, I. Schirmacher, J. Schmidt, S. Schmidt, J. Schneider, S. Schnitt, A. Schwarz, H. Siebert, H. Sodemann, T. Sperzel, G. Spreen, B. Stevens, F. Stratmann, G. Svensson, C. Tatzelt, T. Tuch, T. Vihma, C. Voigt, L. Volkmer, A. Walbröl, A. Weber, B. Wehner, B. Wetzel, M. Wirth, and T. Zinner (2024): Overview: Quasi-Lagrangian observations of Arctic air mass transformations – Introduction and initial results of the HALO–(AC)3 aircraft campaign. EGUsphere 2024, Preprint, 1–46. doi: 10.5194/egusphere-2024-783.

Ebert, M., R. Weigel, S. Weinbruch, L. Schneider, K. Kandler, S. Lauterbach, F. Köllner, F. Plöger, G. Günther, B. Vogel, and S. Borrmann (2024): Characterization of refractory aerosol particles collected in the tropical upper troposphere-lower stratosphere (UTLS) within the Asian Tropopause Aerosol Layer (ATAL). Atmospheric Chemistry and Physics 24 (8), 4771-4788. doi: 10.5194/acp-24-4771-2024.

Yu, P., S. Lian, Y. Zhu, O. B. Toon, M. Höpfner, and S. Borrmann (2022): Abundant Nitrate and Nitric Acid Aerosol in the Upper Troposphere and Lower Stratosphere. Geophysical Research Letters 49 (18), e2022GL100258. doi: https://doi.org/10.1029/2022GL100258.