ACP - recent papers

1. How to trace the origins of short-lived atmospheric species: an Arctic example
   How to trace the origins of short-lived atmospheric species: an Arctic example Anderson Da Silva, Louis Marelle, Jean-Christophe Raut, Yvette Gramlich, Karolina Siegel, Sophie L. Haslett, Claudia Mohr, and Jennie L. Thomas Atmos. Chem. Phys., 25, 5331–5354, https://doi.org10.5194/acp-25-5331-2025, 2025 Particle sources in polar climates are unclear, affecting climate representation in models. This study introduces an evaluated method for tracking particles with backward modeling. Tests on simulated particles allowed us to show that traditional detection methods often misidentify sources. An improved method that accurately traces the origins of aerosol particles in the Arctic is presented. The study recommends using this enhanced method for better source identification of atmospheric species.
2. Evidence of successful methane mitigation in one of Europe's most important oil production region
   Evidence of successful methane mitigation in one of Europe's most important oil production region Gerrit Kuhlmann, Foteini Stavropoulou, Stefan Schwietzke, Daniel Zavala-Araiza, Andrew Thorpe, Andreas Hueni, Lukas Emmenegger, Andreea Calcan, Thomas Röckmann, and Dominik Brunner Atmos. Chem. Phys., 25, 5371–5385, https://doi.org10.5194/acp-25-5371-2025, 2025 A measurement campaign in 2019 found that methane emissions from oil and gas in Romania were significantly higher than reported. In 2021, our follow-up campaign using airborne remote sensing showed a marked decreases in emissions by 20 %–60 % due to improved infrastructure. The study highlights the importance of measurement-based emission monitoring and illustrates the value of a multi-scale assessment integrating ground-based observations with large-scale airborne remote sensing campaigns.
3. Measurement report: Long-term assessment of primary and secondary organic aerosols in the Shanghai megacity throughout China's Clean Air actions since 2010
   Measurement report: Long-term assessment of primary and secondary organic aerosols in the Shanghai megacity throughout China's Clean Air actions since 2010 Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, and Jianlin Hu Atmos. Chem. Phys., 25, 5355–5369, https://doi.org10.5194/acp-25-5355-2025, 2025 This study presents long-term measurements and comprehensive analysis of carbonaceous aerosols in fine particles in Shanghai. We further estimated primary and secondary carbon levels, examining their temporal variations on interannual, monthly, seasonal, and diurnal scales. Through rigorous statistical analysis and correlation studies with meteorological parameters and pollutant concentrations, the origins, formation mechanisms, and spatial distribution patterns of secondary organic carbon were elucidated.
4. The critical number and size of precipitation embryos to accelerate warm rain initiation
   The critical number and size of precipitation embryos to accelerate warm rain initiation Jung-Sub Lim, Yign Noh, Hyunho Lee, and Fabian Hoffmann Atmos. Chem. Phys., 25, 5313–5329, https://doi.org10.5194/acp-25-5313-2025, 2025 Rain formation in warm clouds begins when small droplets collide, but this process can be slow without larger droplets. We used simulations to explore the role of bigger droplets, known as precipitation embryos, in triggering rain. We found that they speed up rain only when their size and number exceed a critical threshold. This threshold becomes larger when collisions are naturally efficient, such as in clouds with broad droplet size distributions or strong turbulence. 
5. Regional and sectoral contributions of NOx and reactive carbon emission sources to global trends in tropospheric ozone during the 2000–2018 period
   Regional and sectoral contributions of NOx and reactive carbon emission sources to global trends in tropospheric ozone during the 2000–2018 period Aditya Nalam, Aura Lupaşcu, Tabish Ansari, and Tim Butler Atmos. Chem. Phys., 25, 5287–5311, https://doi.org10.5194/acp-25-5287-2025, 2025 Tropospheric O3 molecules are labeled with the identity of their precursor source to simulate contributions from various emission sources to the global tropospheric O3 burden (TOB) and its trends. With an equatorward shift, anthropogenic NOx emissions become significantly more efficient at producing O3 and play a major role in driving TOB trends, mainly due to larger convection at the tropics effectively lifting O3 and its precursors to the free troposphere, where O3 lifetime is longer.