Primary Marine Aerosol Production: Studies using bubble-bursting experiments
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Aerosol particles affect the Earth’s climate, although their impact is associated with large uncertainties. Primary marine aerosol represents a significant fraction of the global aerosol budget considering the Earth’s 70-percentage coverage by oceans. They are produced when bubbles burst at the ocean surface and can consist of sea salt, organic matter and bacteria. An experimental approach was here used to investigate the primary marine aerosol production from the bubble-bursting mechanism using water from four different geographical locations. The main findings include:
- Similar and stable aerosol number size distributions at all locations, centered close to 0.2 μm.
- Largely varying aerosol organic fractions, both with size and location.
- Clear tendency for increased water temperature to negatively influence the aerosol production.
- No covariance between surface water chlorophyll α and aerosol production on a 10-minute time scale, although decreased aerosol production was observed at times of elevated phytoplankton activity on longer time scales.
- Mainly external mixtures of sea salt and organics was observed.
- A high tendency for colony-forming marine bacteria to use bubble-bursting to reach the atmosphere.
- A clear diurnal cycle in aerosol production was found for both laboratory produced aerosol and in-situ aerosol fluxes, probably biologically driven.
- The first near coastal sea spray fluxes with limited fetch and low salinity.
While the primary marine aerosol spectral shape is stable, emission concentration varies with environmental parameters. Above that, the organic fraction of the aerosol varies largely between locations. This shows that observations of primary marine aerosol emissions not necessarily can be applied to large time- or spatial scales.
Place, publisher, year, edition, pages
Stockholm: Department of Applied Environmental Science (ITM), Stockholm University , 2010. , 44 p.
sea spray, water temperature, dissolved oxygen, photosynthesis, bacterial emissions, V-TDMA, mixing state, eddy covariance
Research subject Applied Environmental Science
IdentifiersURN: urn:nbn:se:su:diva-43544ISBN: 978-91-7447-159-5OAI: oai:DiVA.org:su-43544DiVA: diva2:357716
2010-12-01, Nordenskiöldsalen, Geovetenskapens hus, Svante Arrhenius väg 12, Stockholm, 10:00 (English)
Swietlicki, Erik, Professor
Nilsson, Douglas, Docent/associate professorKrejci, Radovan, Ph.D.Cousins, Ian, Docent/associate professorHagström, Åke, Professor
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press. Paper 3: Manuscript. Paper 4: Manuscript.
List of papers