Marine aerosol influences cloud formation and climate through both primary sea-spray particles and secondary particles formed from ocean-derived vapours. We investigate the abundance and size distribution of sea-spray aerosol, marine new particle formation, and the growth of nanoparticles to sizes relevant for cloud condensation nuclei (CCN). Our field observations have shown that submicrometre sea spray can be obscured by other aerosol populations, potentially leading to an underestimation of its contribution to marine cloud condensation nuclei.
We also investigate the chemical processes controlling marine particle growth and cloud activation. Marine observations and targeted laboratory experiments are used to examine how heterogeneous iodine-organic reactions accelerate the early growth of iodine-oxide nanoparticles and how the condensation of biogenic organic and inorganic vapours enables secondary marine particles to reach CCN-relevant sizes. Measurements of particle composition, hygroscopicity, and mixing state help determine their cloud activation potential and connect ocean-derived emissions and molecular-scale chemistry with marine aerosol-cloud interactions.
Representative publications
1. Xu, W., Ovadnevaite, J., Fossum, K. N., Lin, C., Huang, R. J.*, Ceburnis, D*, O’Dowd, C*: Sea spray as an obscured source for marine cloud nuclei, Nature Geoscience, 15, 282-286, 2022.
2. Huang, R. J.*, Hoffmann, T., Ovadnevaite, J., Laaksonen, A., Kokkola, H., Xu, W., Xu, W., Ceburnis, D., Zhang, R. Y., Seinfeld, J. H., O’Dowd, C.: Heterogeneous iodine-organic chemistry fast-tracks marine new particle formation, PNAS, 119, e2201729119, DOI: 10.1073/pnas.2201729119, 2022.
3. Xu, W., Ovadnevaite, J., Fossum, K. N., Huang, R. J.*, Huang, D. D., Zhong, H. B., Gu, Y. F., Lin, C. S., Huang, C., O’Dowd, C.*, Ceburnis, D.*: Condensation of organic-inorganic vapours governs the production of ultrafine secondary marine cloud nuclei, Commun. Earth Environ., 5, 359, DOI: 10.1038/s43247-024-01519-z, 2024.
4. Xu, W., Fossum, K. N., Ovadnevaite, J., Lin, C., Huang, R. J.*, O’Dowd, C.*, Ceburnis, D.: The impact of aerosol size-dependent hygroscopicity and mixing state on the cloud condensation nuclei potential over the north-east Atlantic. Atmos. Chem. Phys., 21, 8655-8675, 2021.
5. Ren, J. Y., Xu, W., Huang, R. J.*, Zhang, F., Wang, Y., Chen, L., Ovadnevaite, J., Ceburnis, D., O'Dowd, C., Sun, Y. L.: Contrasting aerosol mixing states at inland and coastal sites: an entropy-based metric for CCN activity, Atmos. Chem. Phys., 26, 2985-3000, 2026.
