Articles | Volume 4, issue 2
https://doi.org/10.5194/ar-4-413-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ar-4-413-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Sep 2026
Research article |
| 09 Sep 2026
| 09 Sep 2026
Coral reef exposure increases aerosol and cloud condensation nuclei over the Great Barrier Reef
Juha Sulo
CORRESPONDING AUTHOR
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
Magdalena Okuljar
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
Joel Alroe
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
Eva Johanna Horchler
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
now at: Department of Chemistry, Aarhus University, Aarhus, Denmark
Luke Cravigan
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
Branka Miljevic
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
Luke Harrison
Reefs and Oceans Research Cluster, National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW, Australia
Daniel Harrison
Reefs and Oceans Research Cluster, National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW, Australia
Zoran Ristovski
School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
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Wenhui Zhao, Yi Huang, Steven Siems, Michael Manton, and Daniel Harrison
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Magdalena Okuljar, Olga Garmash, Miska Olin, Joni Kalliokoski, Hilkka Timonen, Jarkko V. Niemi, Pauli Paasonen, Jenni Kontkanen, Yanjun Zhang, Heidi Hellén, Heino Kuuluvainen, Minna Aurela, Hanna E. Manninen, Mikko Sipilä, Topi Rönkkö, Tuukka Petäjä, Markku Kulmala, Miikka Dal Maso, and Mikael Ehn
Atmos. Chem. Phys., 23, 12965–12983, https://doi.org/10.5194/acp-23-12965-2023, https://doi.org/10.5194/acp-23-12965-2023, 2023
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Zijun Li, Noora Hyttinen, Miika Vainikka, Olli-Pekka Tikkasalo, Siegfried Schobesberger, and Taina Yli-Juuti
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Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
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Zijun Li, Angela Buchholz, Luis M. F. Barreira, Arttu Ylisirniö, Liqing Hao, Iida Pullinen, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 23, 203–220, https://doi.org/10.5194/acp-23-203-2023, https://doi.org/10.5194/acp-23-203-2023, 2023
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Interaction between NOx and biogenic emissions can be important in suburban areas. Our study showed that the addition of NOx during α-pinene SOA formation produced considerable amounts of organic nitrates and affected the composition of non-nitrated organic compounds. The compositional difference consequently altered the primary type of aqueous-phase processes during the isothermal particle evaporation.
Miska Olin, Magdalena Okuljar, Matti P. Rissanen, Joni Kalliokoski, Jiali Shen, Lubna Dada, Markus Lampimäki, Yusheng Wu, Annalea Lohila, Jonathan Duplissy, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 8097–8115, https://doi.org/10.5194/acp-22-8097-2022, https://doi.org/10.5194/acp-22-8097-2022, 2022
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Atmospheric new particle formation is an important source of the total particle number concentration in the atmosphere. Several parameters for predicting new particle formation events have been suggested before, but the results have been inconclusive. This study proposes an another predicting parameter, related to a specific type of highly oxidized organic molecules, especially for similar locations to the measurement site in this study, which was a coastal agricultural site in Finland.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
Atmos. Chem. Phys., 22, 2419–2445, https://doi.org/10.5194/acp-22-2419-2022, https://doi.org/10.5194/acp-22-2419-2022, 2022
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Coral reefs have been found to produce the climatically relevant chemical compound dimethyl sulfide (DMS). It has been suggested that corals can modify their environment via the production of DMS. We use an atmospheric chemistry model to test this theory at a regional scale for the first time. We find that it is unlikely that coral-reef-derived DMS has an influence over local climate, in part due to the proximity to terrestrial and anthropogenic aerosol sources.
Zijun Li, Angela Buchholz, Arttu Ylisirniö, Luis Barreira, Liqing Hao, Siegfried Schobesberger, Taina Yli-Juuti, and Annele Virtanen
Atmos. Chem. Phys., 21, 18283–18302, https://doi.org/10.5194/acp-21-18283-2021, https://doi.org/10.5194/acp-21-18283-2021, 2021
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We compared the evolution of two types of secondary organic aerosol (SOA) particles during isothermal evaporation. The sesquiterpene SOA particles demonstrated higher resilience to evaporation than α-pinene SOA particles generated under comparable conditions. In-depth analysis showed that under high-relative-humidity conditions, particulate water drove the evolution of particulate constituents by reducing the particle viscosity and initiating chemical aqueous-phase processes.
Mao Xiao, Christopher R. Hoyle, Lubna Dada, Dominik Stolzenburg, Andreas Kürten, Mingyi Wang, Houssni Lamkaddam, Olga Garmash, Bernhard Mentler, Ugo Molteni, Andrea Baccarini, Mario Simon, Xu-Cheng He, Katrianne Lehtipalo, Lauri R. Ahonen, Rima Baalbaki, Paulus S. Bauer, Lisa Beck, David Bell, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, António Dias, Jonathan Duplissy, Henning Finkenzeller, Hamish Gordon, Victoria Hofbauer, Changhyuk Kim, Theodore K. Koenig, Janne Lampilahti, Chuan Ping Lee, Zijun Li, Huajun Mai, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Serge Mathot, Roy L. Mauldin, Wei Nie, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Simone Schuchmann, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Robert Wagner, Yonghong Wang, Lena Weitz, Daniela Wimmer, Yusheng Wu, Chao Yan, Penglin Ye, Qing Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Ken Carslaw, Joachim Curtius, Armin Hansel, Rainer Volkamer, Paul M. Winkler, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Jasper Kirkby, Neil M. Donahue, Urs Baltensperger, Imad El Haddad, and Josef Dommen
Atmos. Chem. Phys., 21, 14275–14291, https://doi.org/10.5194/acp-21-14275-2021, https://doi.org/10.5194/acp-21-14275-2021, 2021
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Experiments at CLOUD show that in polluted environments new particle formation (NPF) is largely driven by the formation of sulfuric acid–base clusters, stabilized by amines, high ammonia concentrations or lower temperatures. While oxidation products of aromatics can nucleate, they play a minor role in urban NPF. Our experiments span 4 orders of magnitude variation of observed NPF rates in ambient conditions. We provide a framework based on NPF and growth rates to interpret ambient observations.
Cited articles
Adler, A. I. and Painsky, A.: Feature Importance in Gradient Boosting Trees with Cross-Validation Feature Selection, Entropy, 24, 687, https://doi.org/10.3390/e24050687, 2022.
Andrews, E., Zabala, I., Carrillo-Cardenas, G., Titos, G., Casquero-Vera, J. A., and Hallar, A. G.: Harmonized aerosol size distribution, cloud condensation nuclei, chemistry and optical properties at 10 sites, Sci. Data, 12, 937, https://doi.org/10.1038/s41597-025-04931-y, 2025.
Ansmann, A., Ohneiser, K., Engelmann, R., Radenz, M., Griesche, H., Hofer, J., Althausen, D., Creamean, J. M., Boyer, M. C., Knopf, D. A., Dahlke, S., Maturilli, M., Gebauer, H., Bühl, J., Jimenez, C., Seifert, P., and Wandinger, U.: Annual cycle of aerosol properties over the central Arctic during MOSAiC 2019–2020 – light-extinction, CCN, and INP levels from the boundary layer to the tropopause, Atmos. Chem. Phys., 23, 12821–12849, https://doi.org/10.5194/acp-23-12821-2023, 2023.
Australian Government: Coral bleaching events | AIMS, https://www.aims.gov.au/research-topics/environmental-issues/coral-bleaching/coral-bleaching-events (last access: 10 February 2025), 2024.
Berkelmans, R.: Time-integrated thermal bleaching thresholds of reefs and their variation on the Great Barrier Reef, Mar. Ecol. Prog. Ser., 229, 73–82, https://doi.org/10.3354/meps229073, 2002.
Braga, R. C., Rosenfeld, D., Hernandez, D., Medcraft, C., Efraim, A., Moser, M., Lucke, J., Doss, A., and Harrison, D.: Cloud processing dominates the vertical profiles of aerosols in marine air masses over the Great Barrier Reef, Atmos. Res., 315, 107928, https://doi.org/10.1016/j.atmosres.2025.107928, 2025.
Breiman, L.: Random Forests, Mach. Learn., 45, 5–32, https://doi.org/10.1023/A:1010933404324, 2001.
Brown, B. E.: Coral bleaching: causes and consequences, Coral Reefs, 16, S129–S138, https://doi.org/10.1007/s003380050249, 1997.
Carslaw, K. S., Lee, L. A., Reddington, C. L., Pringle, K. J., Rap, A., Forster, P. M., Mann, G. W., Spracklen, D. V., Woodhouse, M. T., Regayre, L. A., and Pierce, J. R.: Large contribution of natural aerosols to uncertainty in indirect forcing, Nature, 503, 67–71, https://doi.org/10.1038/nature12674, 2013.
Chen, Z., Schofield, R., Rayner, P., Zhang, T., Liu, C., Vincent, C., Fiddes, S., Ryan, R. G., Alroe, J., Ristovski, Z. D., Humphries, R. S., Keywood, M. D., Ward, J., Paton-Walsh, C., Naylor, T., and Shu, X.: Characterization of aerosols over the Great Barrier Reef: The influence of transported continental sources, Sci. Total Environ., 690, 426–437, https://doi.org/10.1016/j.scitotenv.2019.07.007, 2019.
Coddington, O., Lean, J. L., Pilewskie, P., Snow, M., and Lindholm, D.: A Solar Irradiance Climate Data Record, Bull. Am. Meteorol. Soc., 97, 1265–1282, https://doi.org/10.1175/BAMS-D-14-00265.1, 2016.
Courtial, L., Roberty, S., Shick, J. M., Houlbrèque, F., and Ferrier-Pagès, C.: Interactive effects of ultraviolet radiation and thermal stress on two reef-building corals, Limnol. Oceanogr., 62, 1000–1013, https://doi.org/10.1002/lno.10481, 2017.
Cropp, R., Gabric, A., van Tran, D., Jones, G., Swan, H., and Butler, H.: Coral reef aerosol emissions in response to irradiance stress in the Great Barrier Reef, Australia, Ambio, 47, 671–681, https://doi.org/10.1007/s13280-018-1018-y, 2018.
Dall'Osto, M., Monahan, C., Greaney, R., Beddows, D. C. S., Harrison, R. M., Ceburnis, D., and O'Dowd, C. D.: A statistical analysis of North East Atlantic (submicron) aerosol size distributions, Atmos. Chem. Phys., 11, 12567–12578, https://doi.org/10.5194/acp-11-12567-2011, 2011.
Deschaseaux, E. S. M., Dunne, E., Schulz, K. G., Eyre, B. D., and Harrison, D. P.: The Central Great Barrier Reef as a Net Source of Climatically Relevant Biogenic Volatile Organic Compounds, J. Geophys. Res.-Oceans, 130, e2024JC021192, https://doi.org/10.1029/2024JC021192, 2025.
Dietzel, A., Bode, M., Connolly, S. R., and Hughes, T. P.: The population sizes and global extinction risk of reef-building coral species at biogeographic scales, Nat. Ecol. Evol., 5, 663–669, https://doi.org/10.1038/s41559-021-01393-4, 2021.
Doshi-Velez, F. and Kim, B.: Towards A Rigorous Science of Interpretable Machine Learning, https://doi.org/10.48550/arXiv.1702.08608, 2017.
Eckert, C., Monteforte, K. I., Harrison, D. P., and Kelaher, B. P.: Exploring Meteorological Conditions and Microscale Temperature Inversions above the Great Barrier Reef through Drone-Based Measurements, Drones, 7, 695, https://doi.org/10.3390/drones7120695, 2023.
Eckert, C., Hernandez-Jaramillo, D. C., Medcraft, C., Harrison, D. P., and Kelaher, B. P.: Drone-Based Measurement of the Size Distribution and Concentration of Marine Aerosols above the Great Barrier Reef, Drones, 8, 292, https://doi.org/10.3390/drones8070292, 2024.
Fiddes, S. L., Woodhouse, M. T., Utembe, S., Schofield, R., Alexander, S. P., Alroe, J., Chambers, S. D., Chen, Z., Cravigan, L., Dunne, E., Humphries, R. S., Johnson, G., Keywood, M. D., Lane, T. P., Miljevic, B., Omori, Y., Protat, A., Ristovski, Z., Selleck, P., Swan, H. B., Tanimoto, H., Ward, J. P., and Williams, A. G.: The contribution of coral-reef-derived dimethyl sulfide to aerosol burden over the Great Barrier Reef: a modelling study, Atmos. Chem. Phys., 22, 2419–2445, https://doi.org/10.5194/acp-22-2419-2022, 2022.
Fossum, K. N., Ovadnevaite, J., Ceburnis, D., Preißler, J., Snider, J. R., Huang, R.-J., Zuend, A., and O'Dowd, C.: Sea-spray regulates sulfate cloud droplet activation over oceans, Npj Clim. Atmos. Sci., 3, 14, https://doi.org/10.1038/s41612-020-0116-2, 2020.
Fox-Kemper, B., Hewitt, H. T., Xiao, C., Aðalgeirsdóttir, G., Drijfhout, S. S., Edwards, T. L., Golledge, N. R., Hemer, M., Kopp, R., Krinner, G., Mix, A., Notz, D., Nowicki, S., Nurhati, I. S., Ruiz, L., Sallée, J.-B., Slangen, A. B. A., and Yu, Y.: Ocean, Cryosphere and Sea Level Change, in: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, S. L., Connors, S. L., Péan, C., Berger, S., Caud, Y., Chen, L., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1211–1362, https://doi.org/10.1017/9781009157896.011, 2021.
Friedman, J. H.: Greedy function approximation: A gradient boosting machine., Ann. Stat., 29, 1189–1232, https://doi.org/10.1214/aos/1013203451, 2001.
Great Barrier Reef Marine Park Authority: Great Barrier Reef (GBR) Features, https://eatlas.org.au/geonetwork/srv/api/records/ac8e8e4f-fc0e-4a01-9c3d-f27e4a8fac3c (last access: 27 February 2025), 2007.
Harris, D. L., Rovere, A., Casella, E., Power, H., Canavesio, R., Collin, A., Pomeroy, A., Webster, J. M., and Parravicini, V.: Coral reef structural complexity provides important coastal protection from waves under rising sea levels, Sci. Adv., 4, eaao4350, https://doi.org/10.1126/sciadv.aao4350, 2018.
Hernandez-Jaramillo, D. C., Medcraft, C., Braga, R. C., Butcherine, P., Doss, A., Kelaher, B., Rosenfeld, D., and Harrison, D. P.: New airborne research facility observes sensitivity of cumulus cloud microphysical properties to aerosol regime over the great barrier reef, Environ. Sci. Atmos., 4, 861–871, https://doi.org/10.1039/D4EA00009A, 2024.
Hernandez-Jaramillo, D. C., Harrison, L., Gunner, G., McGrath, A., Junkermann, W., Lieff, W., Hacker, J., Rosenfeld, D., Kelaher, B., and Harrison, D. P.: First generation outdoor marine cloud brightening trial increases aerosol concentration at cloud base height, Environ. Res. Lett., 20, 054065, https://doi.org/10.1088/1748-9326/adccd7, 2025.
Hersbach, H., Bell, B., Berrisford, P., Biavati, G., Horányi, A., Muñoz Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Dee, D., and Thépaut, J.-N.: ERA5 hourly data on single levels from 1940 to present, Copernicus Climate Change Service (C3S) Climate Data Store (CDS), https://doi.org/10.24381/cds.adbb2d47, 2023.
Hoppel, W. A., Fitzgerald, J. W., and Larson, R. E.: Aerosol size distributions in air masses advecting off the east coast of the United States, J. Geophys. Res.-Atmos., 90, 2365–2379, https://doi.org/10.1029/JD090iD01p02365, 1985.
Horchler, E. J., Alroe, J., Harrison, L., Cravigan, L., Harrison, D. P., and Ristovski, Z. D.: Measurement report: Aerosol and cloud nuclei properties along the Central and Northern Great Barrier Reef – impact of continental emissions, Atmos. Chem. Phys., 25, 10075–10087, https://doi.org/10.5194/acp-25-10075-2025, 2025.
Hughes, T. P., Barnes, M. L., Bellwood, D. R., Cinner, J. E., Cumming, G. S., Jackson, J. B. C., Kleypas, J., van de Leemput, I. A., Lough, J. M., Morrison, T. H., Palumbi, S. R., van Nes, E. H., and Scheffer, M.: Coral reefs in the Anthropocene, Nature, 546, 82–90, https://doi.org/10.1038/nature22901, 2017a.
Hughes, T. P., Kerry, J. T., Álvarez-Noriega, M., Álvarez-Romero, J. G., Anderson, K. D., Baird, A. H., Babcock, R. C., Beger, M., Bellwood, D. R., Berkelmans, R., Bridge, T. C., Butler, I. R., Byrne, M., Cantin, N. E., Comeau, S., Connolly, S. R., Cumming, G. S., Dalton, S. J., Diaz-Pulido, G., Eakin, C. M., Figueira, W. F., Gilmour, J. P., Harrison, H. B., Heron, S. F., Hoey, A. S., Hobbs, J.-P. A., Hoogenboom, M. O., Kennedy, E. V., Kuo, C., Lough, J. M., Lowe, R. J., Liu, G., McCulloch, M. T., Malcolm, H. A., McWilliam, M. J., Pandolfi, J. M., Pears, R. J., Pratchett, M. S., Schoepf, V., Simpson, T., Skirving, W. J., Sommer, B., Torda, G., Wachenfeld, D. R., Willis, B. L., and Wilson, S. K.: Global warming and recurrent mass bleaching of corals, Nature, 543, 373–377, https://doi.org/10.1038/nature21707, 2017b.
Humphries, R. S., McRobert, I. M., Ponsonby, W. A., Ward, J. P., Keywood, M. D., Loh, Z. M., Krummel, P. B., and Harnwell, J.: Identification of platform exhaust on the RV Investigator, Atmos. Meas. Tech., 12, 3019–3038, https://doi.org/10.5194/amt-12-3019-2019, 2019.
Humphries, R. S., Keywood, M. D., Gribben, S., McRobert, I. M., Ward, J. P., Selleck, P., Taylor, S., Harnwell, J., Flynn, C., Kulkarni, G. R., Mace, G. G., Protat, A., Alexander, S. P., and McFarquhar, G.: Southern Ocean latitudinal gradients of cloud condensation nuclei, Atmos. Chem. Phys., 21, 12757–12782, https://doi.org/10.5194/acp-21-12757-2021, 2021a.
Humphries, R. S., Keywood, M. D., Gribben, S., McRobert, I. M., Ward, J. P., Selleck, P., Taylor, S., Harnwell, J., Flynn, C., Kulkarni, G. R., Mace, G. G., Protat, A., Alexander, S. P., and McFarquhar, G.: Southern Ocean latitudinal gradients of cloud condensation nuclei, Atmos. Chem. Phys., 21, 12757–12782, https://doi.org/10.5194/acp-21-12757-2021, 2021b.
Humphries, R. S., Keywood, M. D., Ward, J. P., Harnwell, J., Alexander, S. P., Klekociuk, A. R., Hara, K., McRobert, I. M., Protat, A., Alroe, J., Cravigan, L. T., Miljevic, B., Ristovski, Z. D., Schofield, R., Wilson, S. R., Flynn, C. J., Kulkarni, G. R., Mace, G. G., McFarquhar, G. M., Chambers, S. D., Williams, A. G., and Griffiths, A. D.: Measurement report: Understanding the seasonal cycle of Southern Ocean aerosols, Atmos. Chem. Phys., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, 2023.
Isokääntä, S., Kim, P., Mikkonen, S., Kühn, T., Kokkola, H., Yli-Juuti, T., Heikkinen, L., Luoma, K., Petäjä, T., Kipling, Z., Partridge, D., and Virtanen, A.: The effect of clouds and precipitation on the aerosol concentrations and composition in a boreal forest environment, Atmos. Chem. Phys., 22, 11823–11843, https://doi.org/10.5194/acp-22-11823-2022, 2022.
Jackson, R., Gabric, A., and Cropp, R.: Effects of ocean warming and coral bleaching on aerosol emissions in the Great Barrier Reef, Australia, Sci. Rep., 8, 14048, https://doi.org/10.1038/s41598-018-32470-7, 2018.
Kangasluoma, J., Cai, R., Jiang, J., Deng, C., Stolzenburg, D., Ahonen, L. R., Chan, T., Fu, Y., Kim, C., Laurila, T. M., Zhou, Y., Dada, L., Sulo, J., Flagan, R. C., Kulmala, M., Petäjä, T., and Lehtipalo, K.: Overview of measurements and current instrumentation for 1–10 nm aerosol particle number size distributions, J. Aerosol Sci., 148, 105584, https://doi.org/10.1016/j.jaerosci.2020.105584, 2020.
Kawana, K., Miyazaki, Y., Omori, Y., Tanimoto, H., Kagami, S., Suzuki, K., Yamashita, Y., Nishioka, J., Deng, Y., Yai, H., and Mochida, M.: Number-Size Distribution and CCN Activity of Atmospheric Aerosols in the Western North Pacific During Spring Pre-Bloom Period: Influences of Terrestrial and Marine Sources, J. Geophys. Res.-Atmos., 127, e2022JD036690, https://doi.org/10.1029/2022JD036690, 2022.
Knowlton, N., Brainard, R. E., Fisher, R., Moews, M., Plaisance, L., and Caley, M. J.: Coral Reef Biodiversity, in: Life in the World's Oceans, John Wiley & Sons, Ltd, 65–78, https://doi.org/10.1002/9781444325508.ch4, 2010.
Krüger, M. L., Mertes, S., Klimach, T., Cheng, Y. F., Su, H., Schneider, J., Andreae, M. O., Pöschl, U., and Rose, D.: Assessment of cloud supersaturation by size-resolved aerosol particle and cloud condensation nuclei (CCN) measurements, Atmos. Meas. Tech., 7, 2615–2629, https://doi.org/10.5194/amt-7-2615-2014, 2014.
Kulmala, M., Junninen, H., Dada, L., Salma, I., Weidinger, T., Thén, W., Vörösmarty, M., Komsaare, K., Stolzenburg, D., Cai, R., Yan, C., Li, X., Deng, C., Jiang, J., Petäjä, T., Nieminen, T., and Kerminen, V.-M.: Quiet new particle formation in the atmosphere, Front. Environ. Sci., 10, 912385, https://doi.org/10.3389/fenvs.2022.912385, 2022.
Laing, J. R., Jaffe, D. A., and Sedlacek, I. I. I. A. J.: Comparison of Filter-based Absorption Measurements of Biomass Burning Aerosol and Background Aerosol at the Mt. Bachelor Observatory, Aerosol Air Qual. Res., 20, 663–678, https://doi.org/10.4209/aaqr.2019.06.0298, 2020.
Law, C. S., Smith, M. J., Harvey, M. J., Bell, T. G., Cravigan, L. T., Elliott, F. C., Lawson, S. J., Lizotte, M., Marriner, A., McGregor, J., Ristovski, Z., Safi, K. A., Saltzman, E. S., Vaattovaara, P., and Walker, C. F.: Overview and preliminary results of the Surface Ocean Aerosol Production (SOAP) campaign, Atmos. Chem. Phys., 17, 13645–13667, https://doi.org/10.5194/acp-17-13645-2017, 2017.
Lundberg, S. M. and Lee, S.-I.: A Unified Approach to Interpreting Model Predictions, in: Advances in Neural Information Processing Systems, 30, 4765–4774, https://proceedings.neurips.cc/paper_files/paper/2017/hash/8a20a8621978632d76c43dfd28b67767-Abstract.html (last access: 3 September 2026), 2017.
Manshausen, P., Watson-Parris, D., Christensen, M. W., Jalkanen, J.-P., and Stier, P.: Invisible ship tracks show large cloud sensitivity to aerosol, Nature, 610, 101–106, https://doi.org/10.1038/s41586-022-05122-0, 2022.
Marelle, L., Myhre, G., Thomas, J. L., and Raut, J.-C.: Aerosol Background Concentrations Influence Aerosol-Cloud Interactions as Much as the Choice of Aerosol-Cloud Parameterization, Geophys. Res. Lett., 52, e2024GL111780, https://doi.org/10.1029/2024GL111780, 2025.
Marto, J. P., Zhang, J., and Schwab, J. J.: Plume analysis from field evaluations of a portable air quality monitoring system, J. Air Waste Manage. Assoc., 71, 70–80, https://doi.org/10.1080/10962247.2020.1834010, 2021.
Milic, A., Mallet, M. D., Cravigan, L. T., Alroe, J., Ristovski, Z. D., Selleck, P., Lawson, S. J., Ward, J., Desservettaz, M. J., Paton-Walsh, C., Williams, L. R., Keywood, M. D., and Miljevic, B.: Biomass burning and biogenic aerosols in northern Australia during the SAFIRED campaign, Atmos. Chem. Phys., 17, 3945–3961, https://doi.org/10.5194/acp-17-3945-2017, 2017.
Modini, R. L., Ristovski, Z. D., Johnson, G. R., He, C., Surawski, N., Morawska, L., Suni, T., and Kulmala, M.: New particle formation and growth at a remote, sub-tropical coastal location, Atmos. Chem. Phys., 9, 7607–7621, https://doi.org/10.5194/acp-9-7607-2009, 2009.
Noble, S. R. and Hudson, J. G.: Effects of Continental Clouds on Surface Aitken and Accumulation Modes, J. Geophys. Res.-Atmos., 124, 5479–5502, https://doi.org/10.1029/2019JD030297, 2019.
Pedregosa, F., Varoquaux, G., Gramfort, A., Michel, V., Thirion, B., Grisel, O., Blondel, M., Prettenhofer, P., Weiss, R., Dubourg, V., Vanderplas, J., Passos, A., Cournapeau, D., Brucher, M., Perrot, M., and Duchesnay, É.: Scikit-learn: Machine Learning in Python, J. Mach. Learn. Res., 12, 2825–2830, 2011.
Peltola, M., Rose, C., Trueblood, J. V., Gray, S., Harvey, M., and Sellegri, K.: New particle formation in coastal New Zealand with a focus on open-ocean air masses, Atmos. Chem. Phys., 22, 6231–6254, https://doi.org/10.5194/acp-22-6231-2022, 2022.
Petters, M. D. and Kreidenweis, S. M.: A single parameter representation of hygroscopic growth and cloud condensation nucleus activity, Atmos. Chem. Phys., 7, 1961–1971, https://doi.org/10.5194/acp-7-1961-2007, 2007.
Reaka-Kudla, M. L.: The global biodiversity of coral reefs: A comparison with rain forests, in: Biodiversity II: Understanding and Protecting Our Biological Resources, edited by: Reaka-Kudla, M. L., Wilson, D. E., and Wilson, E. O., Joseph Henry Press, Washington, D.C., 83–108, https://www.nationalacademies.org/publications/4901 (last access: 20 January 2025), 1997.
Richards, L. S., Siems, S. T., Huang, Y., Zhao, W., Harrison, D. P., Manton, M. J., and Reeder, M. J.: The meteorological drivers of mass coral bleaching on the central Great Barrier Reef during the 2022 La Niña, Sci. Rep., 14, 23867, https://doi.org/10.1038/s41598-024-74181-2, 2024.
Riemer, N., Ault, A. P., West, M., Craig, R. L., and Curtis, J. H.: Aerosol Mixing State: Measurements, Modeling, and Impacts, Rev. Geophys., 57, 187–249, https://doi.org/10.1029/2018RG000615, 2019.
Rowland, M. J., Lambrides ,Ariana B. J., McNiven ,Ian J., and and Ulm, S.: Great Barrier Reef Indigenous archaeology and occupation of associated reef and continental islands, Australas. J. Environ. Manag., 32, 22–45, https://doi.org/10.1080/14486563.2024.2336969, 2025.
Ryan, R. G., Eckert, C., Kelaher, B. P., Harrison, D. P., and Schofield, R.: Boundary layer height above the Great Barrier Reef studied using drone and Mini-Micropulse LiDAR measurements, J. South. Hemisphere Earth Syst. Sci., 74, ES24008, https://doi.org/10.1071/ES24008, 2024.
Santavy, D. L., Horstmann, C. L., Sharpe, L. M., Yee, S. H., and Ringold, P.: What is it about coral reefs? Translation of ecosystem goods and services relevant to people and their well-being, Ecosphere Wash. DC, 12, 1–27, https://doi.org/10.1002/ecs2.3639, 2021.
Schmale, J., Henning, S., Henzing, B., Keskinen, H., Sellegri, K., Ovadnevaite, J., Bougiatioti, A., Kalivitis, N., Stavroulas, I., Jefferson, A., Park, M., Schlag, P., Kristensson, A., Iwamoto, Y., Pringle, K., Reddington, C., Aalto, P., Äijälä, M., Baltensperger, U., Bialek, J., Birmili, W., Bukowiecki, N., Ehn, M., Fjæraa, A. M., Fiebig, M., Frank, G., Fröhlich, R., Frumau, A., Furuya, M., Hammer, E., Heikkinen, L., Herrmann, E., Holzinger, R., Hyono, H., Kanakidou, M., Kiendler-Scharr, A., Kinouchi, K., Kos, G., Kulmala, M., Mihalopoulos, N., Motos, G., Nenes, A., O'Dowd, C., Paramonov, M., Petäjä, T., Picard, D., Poulain, L., Prévôt, A. S. H., Slowik, J., Sonntag, A., Swietlicki, E., Svenningsson, B., Tsurumaru, H., Wiedensohler, A., Wittbom, C., Ogren, J. A., Matsuki, A., Yum, S. S., Myhre, C. L., Carslaw, K., Stratmann, F., and Gysel, M.: Collocated observations of cloud condensation nuclei, particle size distributions, and chemical composition, Sci. Data, 4, 170003, https://doi.org/10.1038/sdata.2017.3, 2017.
Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, 3rd edn., John Wiley & Sons, Inc., Hoboken, New Jersey, ISBN 9781119221173, 2016.
Sihto, S.-L., Mikkilä, J., Vanhanen, J., Ehn, M., Liao, L., Lehtipalo, K., Aalto, P. P., Duplissy, J., Petäjä, T., Kerminen, V.-M., Boy, M., and Kulmala, M.: Seasonal variation of CCN concentrations and aerosol activation properties in boreal forest, Atmos. Chem. Phys., 11, 13269–13285, https://doi.org/10.5194/acp-11-13269-2011, 2011.
Stein, A. F., Draxler, R. R., Rolph, G. D., Stunder, B. J. B., Cohen, M. D., and Ngan, F.: NOAA's HYSPLIT Atmospheric Transport and Dispersion Modeling System, Bull. Am. Meteorol. Soc., 96, 2059–2077, https://doi.org/10.1175/BAMS-D-14-00110.1, 2015.
Storelvmo, T., Leirvik, T., Lohmann, U., Phillips, P. C. B., and Wild, M.: Disentangling greenhouse warming and aerosol cooling to reveal Earth's climate sensitivity, Nat. Geosci., 9, 286–289, https://doi.org/10.1038/ngeo2670, 2016.
Sulo, J., Okuljar, M., Alroe, J., Li, Z., Horchler, E. J., Cravigan, L., Miljevic, B., Harrison, L., Harrison, D., and Ristovski, Z.: Coral reef emissions enhance aerosol and cloud-condensation nuclei concentrations over the Great Barrier Reef, Figshare [data set], https://doi.org/10.6084/m9.figshare.30193285.v1, 2025.
Swan, H. B.: The Potential for Great Barrier Reef Regional Climate Regulation via Dimethylsulfide Atmospheric Oxidation Products, Front. Mar. Sci., 9, https://doi.org/10.3389/fmars.2022.869166, 2022.
Swan, H. B., Crough, R. W., Vaattovaara, P., Jones, G. B., Deschaseaux, E. S. M., Eyre, B. D., Miljevic, B., and Ristovski, Z. D.: Dimethyl sulfide and other biogenic volatile organic compound emissions from branching coral and reef seawater: potential sources of secondary aerosol over the Great Barrier Reef, J. Atmos. Chem., 73, 303–328, https://doi.org/10.1007/s10874-016-9327-7, 2016.
Tessendorf, S. A., Weeks, C. E., Axisa, D., and Bruintjes, R. T.: Aerosol characteristics observed in southeast Queensland and implications for cloud microphysics, J. Geophys. Res.-Atmos., 118, 2858–2871, https://doi.org/10.1002/jgrd.50274, 2013.
Vaattovaara, P., Swan, H. B., Jones, G. B., Deschaseaux, E., Miljevic, B., Laaksonen, A., and Ristovski, Z. D.: The Contribution of Sulfate and Oxidized Organics in Climatically Important Ultrafine Particles at a Coral Reef Environment, Zenodo, https://doi.org/10.5281/zenodo.1092156, 2014.
Wiedensohler, A., Wiesner, A., Weinhold, K., Birmili, W., Hermann, M., Merkel, M., Müller, T., Pfeifer, S., Schmidt, A., Tuch, T., Velarde, F., Quincey, P., Seeger, S., and Nowak, A.: Mobility particle size spectrometers: Calibration procedures and measurement uncertainties, Aerosol Sci. Technol., 52, 146–164, https://doi.org/10.1080/02786826.2017.1387229, 2018.
Yang, L. and Shami, A.: On hyperparameter optimization of machine learning algorithms: Theory and practice, Neurocomputing, 415, 295–316, https://doi.org/10.1016/j.neucom.2020.07.061, 2020.
Zhao, W., Huang, Y., Siems, S., and Manton, M.: A characterization of clouds over the Great Barrier Reef and the role of local forcing, Int. J. Climatol., 42, 6647–6664, https://doi.org/10.1002/joc.7660, 2022.
Zhao, W., Huang, Y., Siems, S., Manton, M., and Harrison, D.: Interactions between trade wind clouds and local forcings over the Great Barrier Reef: a case study using convection-permitting simulations, Atmos. Chem. Phys., 24, 5713–5736, https://doi.org/10.5194/acp-24-5713-2024, 2024.
Short summary
The Great Barrier Reef is the world’s largest coral reef system, and the air above it plays a role in cloud formation. Using direct measurements taken over several years, this study shows that although the reef has low aerosol concentrations, air that passes directly over coral reefs contains more very small particles, providing the first direct evidence that reefs add particles to the atmosphere. These locally produced particles make a measurable contribution to cloud formation over the reef.
The Great Barrier Reef is the world’s largest coral reef system, and the air above it plays a...
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