[1] A major source of the primary marine aerosol is the bursting of air bubbles produced by breaking waves. Several source parameterizations are available from the literature, usually limited to particles with a dry diameter D p > 1 mm. The objective of this work is to extend the current knowledge to submicrometer particles. Bubbles were generated in synthetic seawater using a sintered glass filter, with a size spectra that are only partly the same spectra as measured in the field. Bubble spectra, and size distributions of the resulting aerosol (0.020-20.0 mm D p ) of the resulting aerosol, were measured for different salinity, water temperature (T w ), and bubble flux. The spectra show a minimum at $1 mm D p , which separates two modes, one at $0.1 mm, with the largest number of particles, and one at 2.5 mm D p . The modes show different behavior with the variation of salinity and water temperature. When the water temperature increases, the number concentration N p decreases for D p < 0.07 mm, whereas for D p > 0.35 mm, N p increases. The salinity effect suggests different droplet formation processes for droplets smaller and larger than 0.2 mm D p . The number of particles produced per size increment, time unit, and whitecap surface (È) is described as a linear function of T w and a polynomial function of D p . Combining È with the whitecap coverage fraction W (in percent), an expression results for the primary marine aerosol source flux dF 0 /dlogD p = W È (m À2 s À1 ). The results are compared with other commonly used formulations as well as with recent field observations. Implications for aerosol-induced effects on climate are discussed.

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Affordable high quality charge-coupled device (CCD) video cameras and image processing software are powerful tools for bubble measurements. Because of the wide variation between bubble populations, different bubble measurement systems (BMSs) are required depending upon the application. Two BMSs are described: a mini-BMS designed to observe the background bubble population from breaking waves, and a large-BMS designed to noninvasively determine the time-resolved bubble distribution inside dense bubble plumes and near the interface, as are details of the analysis techniques. Using the two systems in conjunction with each other allowed size distributions over the range 15-5000-m radius to be obtained. The BMSs were designed for application to breaking-wave bubble plumes in the field or laboratory. Distributions measured by both BMSs in aerator-generated plumes agreed very well for the overlapping size range. Also presented are observations of bubble plumes produced by breaking waves in a large wind-wave flume, and calibration experiments showing the effect on measured bubble size due to blur induced by slow shutter speeds.

The Rough Evaporation Duct experiment aimed to see if the effects of ocean waves account for errors in modeling the ranges at which radar and infrared can detect low-flying targets. When radars first came into operation during the late 1930s, they were not expected to detect targets much beyond the geometrical horizon. These early radars, operating at a wavelength of 13 m, generally met expectations. As new radars were rapidly developed, operating at shorter and shorter wavelengths for better target detection, observations of anomalous propagation effects became more frequent. When 10-cm radars were installed along the south coast of England during World War II, they were often able to see the coast of France, even though the coast was well beyond the geometric horizon (Booker 1948). These anomalous propagation effects also became more pronounced as the operating area became more tropical. For example, a 1.5-mwavelength radar operating in Bombay, India, re-

This iaper discusses techniques to describe the aerosol and the electro optical properties of the marine atmosphere from 15 meters down to the tops of the highest wave. Emphasis is placed on the experimental Rotorod technique to measure the concentrations of giant sea salt droplets. Data from these devices are parameterized using a lognormal function that is in turn related statistically to parameters such as wind speed, atmospheric stability and height above the surface. The new lognormal function is combined with the Navy Aerosol Model (NAM) to develop a first version of the Advanced Navy Aerosol Model ANAM). Thus, ANAM allows the construction of an aerosol size distribution at any level from the wave tops to 15 meters and the assessment of electro optical parameters from this distribution using Mie theory. The first results of the ANA1\'I model are compared to experimental data.