Project Details
Projekt
Contributions of upper tropospheric new particle formation, biomass burning and marine aerosols to the cloud nuclei population in South America
Applicant
Professorin Dr. Mira Pöhlker
Subject Area
Atmospheric Science
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 564856519
Atmospheric aerosols play a crucial role in cloud formation and climate regulation, yet their sources, concentrations, and properties across the atmospheric vertical structure remain insufficiently understood. In the upper troposphere (UT), new particle formation (NPF) is a key process, particularly in tropical regions such as the Amazon. Biogenic volatile organic compounds (BVOCs), transported upward by deep convective clouds, undergo oxidation, reducing precursor gas volatility and enhancing NPF due to a minimized condensational sink. Additionally, particle nucleation in the lower stratosphere (LS), triggered by volcanic eruptions or overshooting convection, contributes to aerosol populations in the UT. These particles, upon growing to sizes capable of acting as cloud condensation nuclei (CCN), influence radiative balance and cloud microphysics. However, significant knowledge gaps persist, including the impact of anthropogenic influences like deforestation on NPF, the complex chemistry in regions with strong stratosphere-troposphere exchange, and the effects of long-range aerosol transport from oceanic sources. To address these uncertainties, I will measure aerosol size distributions (2 nm to 2.5 µm) and CCN concentrations during the CONTANGO-FIRE mission, planned for early 2028 in Argentina. Single particle analyses of aerosol samples taken during the campaign will be used to differentiate aerosol sources and investigate particle ageing and mixing processes. This research aims to advance understanding of aerosol contributions to the global CCN budget and their implications for climate and cloud dynamics.
DFG Programme
Infrastructure Priority Programmes
