Stratospheric air intrusions promote global-scale new particle formation

Autor(en)

Jiaoshi Zhang, Xianda Gong, Ewan Crosbie, Glenn Diskin, Karl Froyd, Samuel Hall, Agnieszka Kupc, Richard Moore, Jeff Peischl, Andrew Rollins, Joshua Schwarz, Michael Shook, Chelsea Thompson, Kirk Ullmann, Christina Williamson, Armin Wisthaler, Lu Xu, Luke Ziemba, Charles A. Brock, Jian Wang

Abstrakt

New particle formation in the free troposphere is a major source of cloud condensation nuclei globally. The prevailing view is that in the free troposphere, new particles are formed predominantly in convective cloud outflows. We present another mechanism using global observations. We find that during stratospheric air intrusion events, the mixing of descending ozone-rich stratospheric air with more moist free tropospheric background results in elevated hydroxyl radical (OH) concentrations. Such mixing is most prevalent near the tropopause where the sulfur dioxide (SO2) mixing ratios are high. The combination of elevated SO2 and OH levels leads to enhanced sulfuric acid concentrations, promoting particle formation. Such new particle formation occurs frequently and over large geographic regions, representing an important particle source in the midlatitude free troposphere.

Organisation(en)

Aerosolphysik und Umweltphysik

Externe Organisation(en)

Washington University in St. Louis, NASA Langley Research Center, Science Systems and Applications, Inc., University of Colorado, Boulder, National Oceanic and Atmospheric Administration, National Center for Atmospheric Research (NCAR), Finnish Meteorological Institute, University of Helsinki, Leopold-Franzens-Universität Innsbruck, University of Oslo

Journal

Science

Band

385

Seiten

210-216

Anzahl der Seiten

7

ISSN

0036-8075

DOI

https://doi.org/10.1126/science.adn2961

Publikationsdatum

07-2024

Peer-reviewed

Ja

ÖFOS 2012

103039 Aerosolphysik, 103037 Umweltphysik, 105208 Atmosphärenchemie, 105204 Klimatologie

ASJC Scopus Sachgebiete

General

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/d2ff08b9-46dc-4359-a68b-53bfbdcb02c6