- Email: [email protected]
The laboratory production of the bubbling fraction of the marine aerosol—application to polluted seawater∗
AtmosphericEnuironmenf Vol. 23, No. 8, p Pnnled in Great Britain.
@X1&6981/89S3.M)+000 Pergamon Press plc
1871, 1989.
DISCUSSION THE LABORATORY PRODUCTION OF THE BUBBLING FRACTION OF THE MARINE AEROSOL-APPLICATION TO POLLUTED SEAWATER* I hope that all workers who study the bubble-produced aerosol get to see this paper. Guichard and Lamauve, here and in earlier papers, have shown quite convincingly that if the bubbles are produced by forcing air through hydrophilic membranes or fritted glass, they will rise to the surface carrying an aerosol that was generated at the time the bubbles were produced. When the bubbles burst at the surface, the number concentration of this aerosol released to the atmosphere can be much greater than that generated by jet and film drops. Only by the use of hydrophobic membranes could they avoid this artificial aerosol production. Some years ago (Cipriano et al., 1983), we suspected that an aerosol was generated as air passed through submerged glass frits. and so we produced an aerosol in a more natural way from the bubbles generated by letting water fall into water (Cipriano and Blanchard, 1981). Guichard and Lamauve give no information on the bubble spectrum produced by their generator. If they can control bubble size by the pore size of their membrane, it would be interesting to look at the aersol from bursting bubbles in the size range of 2-2.5 mm diameter. It is in this size range that we (Blanchard and Syzdek, 1988) found by far the most film drops. About 75 film drops per bubble were found, but on either side of this peak (bubbles of 1.5 and 2.8 mm), film drop production was < 5 per bubble.
*Guichard J. C. and Lamauve Environment 22, 1835-1838.
M. (1988) Atmospheric
1871
Guichard and Lamauve have used their Teflon membrane bubble generator to study changes in aerosol production when surface-active agents were placed on the water. Their data are preliminary but more extensive experiments are to be made. I encourage such experiments since the increase in organic pollutants along the seashore almost certainly is modifying aerosol production. When they analyze their data, I hope they will compare it with Garrett‘s (1967, 1968). He studied the influence of monomolecular films both on the stabilization of air bubbles at the surface and on their aerosol production. Unfortunately, however, in some of the work he used a glass frit!
REFERENCES
Blanchard D. C. and Syzdek L. D. (1988) Film drop production as a function of bubble size. J. geophys. Res. 93, 3649-3654. Cipriano R. J. and Blanchard D.C. (1981) Bubble and aerosol spectra produced by a laboratory ‘breaking wave.’ J. geophys. Res. 86, 8085-8092. Cipriano R. J., Blanchard D. C., Hogan A. W. and Lala G. G. (1983) On the production of Aitken nuclei from breaking waves and their role in the atmosphere. J. atmos. Sci. 40, 469479. Garrett W. D. (1967) Stabilization of air bubbles at the air-sea interface by surface-active material. Deep-Sea Res. 14,661-672. Garrett W. D. (1968) The influence of monomolecular surface films on the production of condensation nuclei from bubbled sea water. J. geophys. Res. 73, 5145-5150.
Atmospheric Sciences DUNCAN Reseurch Center, State University of New York at Albany, Albany, NY 12222, U.S.A.
C. BLANCHARD
@X1&6981/89S3.M)+000 Pergamon Press plc
1871, 1989.
DISCUSSION THE LABORATORY PRODUCTION OF THE BUBBLING FRACTION OF THE MARINE AEROSOL-APPLICATION TO POLLUTED SEAWATER* I hope that all workers who study the bubble-produced aerosol get to see this paper. Guichard and Lamauve, here and in earlier papers, have shown quite convincingly that if the bubbles are produced by forcing air through hydrophilic membranes or fritted glass, they will rise to the surface carrying an aerosol that was generated at the time the bubbles were produced. When the bubbles burst at the surface, the number concentration of this aerosol released to the atmosphere can be much greater than that generated by jet and film drops. Only by the use of hydrophobic membranes could they avoid this artificial aerosol production. Some years ago (Cipriano et al., 1983), we suspected that an aerosol was generated as air passed through submerged glass frits. and so we produced an aerosol in a more natural way from the bubbles generated by letting water fall into water (Cipriano and Blanchard, 1981). Guichard and Lamauve give no information on the bubble spectrum produced by their generator. If they can control bubble size by the pore size of their membrane, it would be interesting to look at the aersol from bursting bubbles in the size range of 2-2.5 mm diameter. It is in this size range that we (Blanchard and Syzdek, 1988) found by far the most film drops. About 75 film drops per bubble were found, but on either side of this peak (bubbles of 1.5 and 2.8 mm), film drop production was < 5 per bubble.
*Guichard J. C. and Lamauve Environment 22, 1835-1838.
M. (1988) Atmospheric
1871
Guichard and Lamauve have used their Teflon membrane bubble generator to study changes in aerosol production when surface-active agents were placed on the water. Their data are preliminary but more extensive experiments are to be made. I encourage such experiments since the increase in organic pollutants along the seashore almost certainly is modifying aerosol production. When they analyze their data, I hope they will compare it with Garrett‘s (1967, 1968). He studied the influence of monomolecular films both on the stabilization of air bubbles at the surface and on their aerosol production. Unfortunately, however, in some of the work he used a glass frit!
REFERENCES
Blanchard D. C. and Syzdek L. D. (1988) Film drop production as a function of bubble size. J. geophys. Res. 93, 3649-3654. Cipriano R. J. and Blanchard D.C. (1981) Bubble and aerosol spectra produced by a laboratory ‘breaking wave.’ J. geophys. Res. 86, 8085-8092. Cipriano R. J., Blanchard D. C., Hogan A. W. and Lala G. G. (1983) On the production of Aitken nuclei from breaking waves and their role in the atmosphere. J. atmos. Sci. 40, 469479. Garrett W. D. (1967) Stabilization of air bubbles at the air-sea interface by surface-active material. Deep-Sea Res. 14,661-672. Garrett W. D. (1968) The influence of monomolecular surface films on the production of condensation nuclei from bubbled sea water. J. geophys. Res. 73, 5145-5150.
Atmospheric Sciences DUNCAN Reseurch Center, State University of New York at Albany, Albany, NY 12222, U.S.A.
C. BLANCHARD