Aircraft-based observation of meteoric material in lower-stratospheric aerosol particles between 15 and 68° N

• Published in: Atmospheric Chemistry and Physics
• Main Authors: J. Schneider, R. Weigel, T. Klimach, A. Dragoneas, O. Appel, A. Hünig, S. Molleker, F. Köllner, H.-C. Clemen, O. Eppers, P. Hoppe, P. Hoor, C. Mahnke, M. Krämer, C. Rolf, J.-U. Grooß, A. Zahn, F. Obersteiner, F. Ravegnani, A. Ulanovsky, H. Schlager, M. Scheibe, G. S. Diskin, J. P. DiGangi, J. B. Nowak, M. Zöger, S. Borrmann
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2021
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Arctic
• Online Access: https://doi.org/10.5194/acp-21-989-2021; https://doaj.org/article/ccb3258ea0c345c5873eadf9a39a5e47

We analyse aerosol particle composition measurements from five research missions between 2014 and 2018 to assess the meridional extent of particles containing meteoric material in the upper troposphere and lower stratosphere (UTLS). Measurements from the Jungfraujoch mountaintop site and a low-altitude aircraft mission show that meteoric material is also present within middle- and lower-tropospheric aerosol but within only a very small proportion of particles. For both the UTLS campaigns and the lower- and mid-troposphere observations, the measurements were conducted with single-particle laser ablation mass spectrometers with bipolar-ion detection, which enabled us to measure the chemical composition of particles in a diameter range of approximately 150 nm to 3 µm . The five UTLS aircraft missions cover a latitude range from 15 to 68 ∘ N, altitudes up to 21 km , and a potential temperature range from 280 to 480 K . In total, 338 363 single particles were analysed, of which 147 338 were measured in the stratosphere. Of these total particles, 50 688 were characterized by high abundances of magnesium and iron, together with sulfuric ions, the vast majority (48 610) in the stratosphere, and are interpreted as meteoric material immersed or dissolved within sulfuric acid. It must be noted that the relative abundance of such meteoric particles may be overestimated by about 10 % to 30 % due to the presence of pure sulfuric acid particles in the stratosphere which are not detected by the instruments used here. Below the tropopause, the observed fraction of the meteoric particle type decreased sharply with 0.2 %–1 % abundance at Jungfraujoch, and smaller abundances (0.025 %–0.05 %) were observed during the lower-altitude Canadian Arctic aircraft measurements. The size distribution of the meteoric sulfuric particles measured in the UTLS campaigns is consistent with earlier aircraft-based mass-spectrometric measurements, with only 5 %–10 % fractions in the smallest particles detected (200–300 nm diameter) but with ...