Sea Spray Aerosols: Results from Laboratory Experiments

Andrew Charles Butcher

Abstract

Aerosols are important climactically. Their specific emissions are key to reducing the uncertainty in global climate models. Marine aerosols make up the largest source of primary aerosols to the Earth's atmosphere. Uncertainty in marine aerosol mass and number flux lies in separating primary emissions produced directly from bubble bursting as the result of air entrainment from breaking waves and particles generated from secondary emissions of volatile organic compounds.
In the first paper, we study the chemical properties of particles produced from several sea water proxies with the use of a cloud condensation nuclei ounter. Proxy solutions with high inorganic salt concentrations and some organics produce sea spray aerosol particles with little change in cloud condensation activity relative to pure salts. Comparison is made between a frit based method for bubble production and a plunging jet in high concentrations of surface active organics and brackish water salinities. The jet produces particles with less cloud condensation activity, implying an increase in organic material in aerosol particles produced by the plunging jet over the frit.
In the second paper we determine a relationship between plunging jet particle ux, oceanic particle ux, and energy dissipation rate in both systems. Previous sea spray aerosol studies dissipate an order of magnitude more energy for the same particle ux production as the open ocean. A scaling factor related to the energy expended in air entrainment may account for the large discrepancy in energy input for the two systems. In the third study, the temperature dependence of sea spray aerosol production is probed with the use of a highly stable temperature controlled plunging jet. Similar to previous studies, particle production increases with decreasing temperature. Unique
surface images of bubble size distributions allow the investigation of temperature, bubble size, and particle production
OriginalsprogEngelsk
ForlagDepartment of Chemistry, Faculty of Science, University of Copenhagen
Antal sider190
ISBN (Trykt)978-87-91963-30-8
StatusUdgivet - 2013

Citationsformater