The importance of upper troposphere aerosol transport and processing for low and mid troposphere aerosol concentrations (C06)

• Subject Area: Atmospheric Science
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428312742

New particle formation (NPF) in the upper troposphere (above 10km altitude) has been proven to occur independently of sulfuric acid over the Amazon. This has been argued to substantially increase tropical cloud condensation nuclei (CCN) concentrations in the preindustrial atmosphere and thus impact the diagnosed historical aerosol-cloud radiative forcing. However, it remains to be shown to which extent these high-altitude sourced particles are indeed mixed down into the atmospheric boundary layer, where they may act as CCN. In this project, we will continue to use ICON simulations (with and without aerosol-processing) to quantify timescales and diagnose CCN budgets sourced specifically from upper troposphere NPF, and NPF from the free troposphere more generally.

• DFG Programme: CRC/Transregios
• Subproject of: TRR 301: The tropopause region in a changing atmosphere
• Applicant Institution: Johannes Gutenberg-Universität Mainz
• Project Heads: Professor Dr. Joachim Curtius; Professorin Dr. Anna Possner; Dr. Andrea Pozzer