| Volumes and Issues Contents of Issue 5 |
www.atmos-meas-tech-discuss.net/2/2281/2009/
© Author(s) 2009. This work is distributed
under the Creative Commons Attribution 3.0 License.
Laboratory-generated primary marine aerosol via bubble-bursting and atomization
1Centre for Atmospheric Sciences, School of Earth, Atmospheric and Environmental Sciences, Manchester M13 9PL, UK
2Scottish Association for Marine Science, Oban, UK
Abstract. A range of bubble and sea spray aerosol generators has been tested in the laboratory and compared with ocean measurements. We have shown that the method of generation has a significant influence on the properties of the aerosol particles produced. Hence, the validity of a generation system to mimic atmospheric aerosol is dependent on its capacity of generating bubbles and particulate in a realistic manner. A bubble-bursting aerosol generator consisting in the production of bubbles by the impingement of water jets on seawater was shown to best reproduce the real oceanic bubble and aerosol distributions signatures.
Two aeration methods and a plunging-water jet system were tested as bubble-bursting aerosol generators for comparison with a standard nebulizer. The methods for aerosol production were evaluated by analysing the bubble spectrum generated by the bubble-bursting systems and the submicron size distribution, hygroscopicity and cloud condensation nucleus activity of the aerosols generated by the different techniques. Significant differences in the bubble spectrum and aerosol properties were observed when using different aerosol generators.
The hygroscopicity and cloud condensation nucleus activity of aerosols generated by the different methods were similar when a sample of purely inorganic salts was used as a parent seawater solution; however, significant differences in the aerosol properties were found when biogenic organics were incorporated in the seawater samples. The presence of organics in the aerosol caused suppression of the growth factor at humidities above 75% RH and an increase in the critical supersaturation when compared with the case without organics. Unequal extent of these effects was observed for aerosols generated by the different methods of particle production. While the highest reductions of the growth factor were observed for the plunging-water jet aerosol, the largest effect on the critical supersaturation was obtained for the atomization-generated particles. The results of this work show that the aerosol generation mechanism affects the particles organic enrichment, thus the behaviour of the produced aerosols strongly depends on the laboratory aerosol generator employed.
Discussion Paper (PDF, 1761 KB) Interactive Discussion (Closed, 3 Comments) Final Revised Paper (AMT)
Citation: Fuentes, E., Coe, H., Green, D., and McFiggans, G.: Laboratory-generated primary marine aerosol via bubble-bursting and atomization, Atmos. Meas. Tech. Discuss., 2, 2281-2320, 2009. Bibtex EndNote Reference Manager
