Approaches to PBAP modelling in EMEP

Primary biological aerosol particles (PBAP) are ubiquitous in the Earth’s atmosphere, and can make significant contributions to measured particulate matter (PM) concentrations [1,2]. They are also known to play an important role in cloud formation and have a significant impact on health [3]. The sources of PBAP, however, are many and complex (e.g., viruses, bacteria, algae, fungae, plant pollen), and PBAP can be emitted from both land and sea sources. Although modelling of pollen has been included in the EMEP MSC-W chemical transport model [4] for many years, other PBAP sources have not been included. This is mainly because of the difficulties in quantifying the magnitude and spatial and temporal distributions at both European and global scale. In this study we review some of the main sources of PBAP, and consider approaches for a more detailed inclusion of these important aerosol particles in the EMEP model. [1] V. R. DesprÅLes et al. Primary biological aerosol particles in the atmosphere: a review, Tellus B: Chemical and Physical Meteorology, 64:1 (2012). [2] K. Yttri et al. Trends, composition, and sources of carbonaceous aerosol at the Birkenes Observatory, northern Europe, 2001–2018, Atmos. Chem. Phys., 21, 7149–7170 (2021). [3] J. FrÅNohlich-Nowoisky et al. Bioaerosols in the Earth system: Climate, health, and ecosystem interactions, Atmospheric Research Volume 182, 346-376 (2016). [4] D. Simpson et al. The EMEP MSC-W chemical transport model – technical description, Atmos. Chem. Phys., 12, 7825–7865 (2012).