Nitric Acid Trihydrate (NAT) in Polar Stratospheric Clouds

• Published in: Science
• Main Authors: Voigt, Christiane, Schreiner, Jochen, Kohlmann, Andreas, Zink, Peter, Mauersberger, Konrad, Larsen, Niels, Deshler, Terry, Kröger, Chris, Rosen, Jim, Adriani, Alberto, Cairo, Francesco, Donfrancesco, Guido Di, Viterbini, Maurizio, Ovarlez, Joelle, Ovarlez, Henri, David, Christine, Dörnbrack, Andreas
• Other Authors: Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, Danish Meteorological Institute (DMI), Department of Atmospheric Science Laramie, University of Wyoming (UW), Istituto di Fisica dell'Atmosfera del CNR (IFA), National Research Council of Italy, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-École nationale des ponts et chaussées (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DLR Institut für Physik der Atmosphäre = DLR Institute of Atmospheric Physics (IPA), Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen-Wessling (DLR)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2000
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Kiruna
• Online Access: https://insu.hal.science/insu-03581885; https://doi.org/10.1126/science.290.5497.1756

International audience A comprehensive investigation of polar stratospheric clouds was performed on 25 January 2000 with instruments onboard a balloon gondola flown from Kiruna, Sweden. Cloud layers were repeatedly encountered at altitudes between 20 and 24 kilometers over a wide range of atmospheric temperatures (185 to 197 kelvin). Particle composition analysis showed that a large fraction of the cloud layers was composed of nitric acid trihydrate (NAT) particles, containing water and nitric acid at a molar ratio of 3:1; this confirmed that these long-sought solid crystals exist well above ice formation temperatures. The presence of NAT particles enhances the potential for chlorine activation with subsequent ozone destruction in polar regions, particularly in early and late winter.