Tropospheric Ambient Radicals in Ground level Environments of Taiwan (TARGET)

• Applicant: Maria Dolores Andrés Hernández, Ph.D.
• Subject Area: Atmospheric Science
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 584785813

Severe pollution episodes with adverse effect on human health are recurrent in high-urbanized areas. The implementation of effective mitigation strategies at a particular site requires a deep understanding of the processes controlling transport and chemical transformation of locally and upwind-emitted pollutants. Oxidation reactions dominate in the chemical processing of atmospheric pollutants resulting in the formation of hazardous secondary products such as ozone and aerosols. In this respect, peroxy radicals are short lived species involved in most of the oxidation processes in the troposphere and in particular in ozone formation and depletion mechanisms. Despite efforts in mitigation strategies smog events remain highly frequent in East Asia. Episodes of unusually high ozone and aerosol concentrations over Taiwan are of major environmental concern. On top of local emission sources, Taiwan receives air pollutants originating in China during winter monsoon and clean air masses from the remote western North Pacific Ocean in the summer season. TARGET seeks to gain an in-depth understanding of the formation of highly polluted episodes in Taiwan. In particular, TARGET aims at addressing existing gaps in knowledge regarding atmospheric oxidation processes and the role of peroxy radicals in the formation of ozone in polluted air masses in Southern Taiwan. With this objective, TARGET proposes a scientific collaboration between Bremen and Taiwan that envisages the acquisition of a comprehensive set of trace gases and aerosol species to investigate the chemistry underlying the variations in ozone and particulate matter in the target area. In this regard, a portable instrument, specifically optimized for the ground-based measurement of peroxy radicals in Taiwan will be developed in Bremen to reduce size, weight and complexity while increasing accuracy and sensitivity of the existing airborne PeRCEAS instrument (Peroxy Radical Chemical Enhancement and Absorption Spectrometer). Overall, TARGET places special emphasis on the combination of intensive observational periods (IOPs) and goal-oriented modelling exercises for a comprehensive analysis of the data obtained. The IOPs are planned to cover different of mixing scenarios of long-range transported air masses with locally emitted pollutants leading to smog events over the year. Dedicated satellite data on tropospheric pollutants will additionally help to identify pollution transport pathways, source and receptor regions. TARGET benefits from the previous experience and expertise of the scientific groups collaborating in Bremen and Taiwan, which is greatly enhanced during the implementation of the work proposed. On top of this, the results of TARGET are expected to provide an extensive data set of measurements and modelling tools for further investigation of smog episodes in East Asia, offering an experimental and modelling groundwork for the implementation of effective mitigation strategies in Taiwan.

• DFG Programme: Research Grants
• International Connection: Taiwan
• Cooperation Partner: Dr. Charles K. Chou, Ph.D.