Tran, Thao LinhFan, JiwenRosenfeld, DanielZhang, YuweiCleugh, HelenHogg, Andrew Mc C.Prinsley, Roslyn2025-05-232025-05-232169-897XORCID:/0000-0003-4379-7008/work/183508753ORCID:/0000-0003-2539-175X/work/183511117ORCID:/0000-0001-5898-7635/work/188301497http://www.scopus.com/inward/record.url?scp=105003135284&partnerID=8YFLogxKhttps://hdl.handle.net/1885/733750645As risks from tropical cyclones (TCs) are fueled by climate change escalation, there is an urgent need for transformational solutions to complement traditional approaches. Seeding TCs using aerosols can be a promising method to reduce cyclone intensity, supported by theoretical understanding of the microphysical effects of aerosols on TC clouds. The ideal time to intervene effectively in TCs is likely during their initial stage, before TC wind speeds reach their peak. However, studies exploring potential aerosol effects on TC formation remain scarce. This study investigates how a TC embryo responds to the addition of aerosols of varying sizes using the Weather Research & Forecasting (WRF) model coupled with a spectral-bin microphysics model. We found that aerosols of different sizes and concentrations distinctively affect the pre-TC vortex's microstructure and dynamics. Fine and ultrafine aerosols enhance the latent heat of condensation, freezing, deposition, and riming, initially intensifying the vortex. However, this results in enhancement of the cold pool, thereby reducing inflow and surface fluxes, subsequently weakening the vortex. Coarse aerosols produce the opposite effect to that of fine and ultrafine aerosols. Coarse aerosols lead to a slower initial acceleration owing to enhanced warm rain. However, the resulting weaker cold pool is insufficient to effectively reduce the strength of the vortex at the later stage. This study provides critical insights into how aerosols of varying sizes and concentrations modulate the energy cascade and impact the evolution of a TC embryo, laying the groundwork for further research on TC risk management through aerosol intervention.This research was undertaken with the assistance of resources and services from the National Computational Infrastructure (NCI), which is supported by the Australian Government. JF's effort was supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research program as part of the Regional and Global Model Analysis and Multi\u2010Sector Dynamics program areas (Award Number DE\u2010SC0016605). Argonne National Laboratory is operated for the DOE by UChicago Argonne, LLC, under contract DE\u2010AC02\u201006CH11357. The authors would like to thank Andy Pitman and Dale Roberts from the ARC Center of Excellence for Climate Extremes, for supporting the compilation of the WRF\u2010FSBM 4.0.3 adjusted version on the NCI's GADI supercomputer system. Open access publishing facilitated by Australian National University, as part of the Wiley \u2010 Australian National University agreement via the Council of Australian University Librarians. This research was undertaken with the assistance of resources and services from the National Computational Infrastructure (NCI), which is supported by the Australian Government. JF's effort was supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research program as part of the Regional and Global Model Analysis and Multi-Sector Dynamics program areas (Award Number DE-SC0016605). Argonne National Laboratory is operated for the DOE by UChicago Argonne, LLC, under contract DE-AC02-06CH11357. The authors would like to thank Andy Pitman and Dale Roberts from the ARC Center of Excellence for Climate Extremes, for supporting the compilation of the WRF-FSBM 4.0.3 adjusted version on the NCI's GADI supercomputer system. Open access publishing facilitated by Australian National University, as part of the Wiley - Australian National University agreement via the Council of Australian University Librarians.21en© 2025 The Author(s)aerosolaerosol-cyclone interactionscold poolconvectioncyclogenesis mitigationtropical cyclone2025-04-2810.1029/2024JD041600105003135284