flux is higher for colder water; above 0.2 µm D p the number flux is higher
for warmer water.
Gong et al. (1997) and Lohmann et al. (2000) extrapolated the Monahan
et al. (1986) parameterization below 0.9 µm (shown in Figure 6-12 with a
dotted line). This extrapolation demonstrates monotonically increasing flux
with decreasing D p below 0.9 µm. The Mårtensson et al. (2003)
parameterization, based on the size spectra observed in the laboratory as well
in the available field data, offers a different dependence for D p < 0.9 Pm.
Figure 6-12. Parameterization (6.22)-(6.24) of the primary aerosol production shown as a
function of the dry particle diameter D p , for a wind speed of 9 m s
-1 and water temperatures
25°C (solid bold line) and 5°C (dashed line). This parameterization is also compared with the
source flux from Monahan et al. (1986) in the size interval 0.9 –11.2 D p µm (solid line) and
extrapolated down to 0.02 µm, i.e., in the size interval 0.020–0.9 µm D p (dotted line). The
In the size range D p = 0.07–0.9 µm, Monahan et al. (1986) may
underestimate the flux, while below 0.07 µm D p , they overestimate the flux,
compared to Mårtensson et al. (2003). The deviation of the Monahan et al.
(1986) parameterization below 1 µm D p is presumably because it is based on
Chapter 6: HIGH WIND SPEED REGIME
423
flux derived by Smith et al. (1993) is shown by a dot-dashed line. Reproduced from Mårtensson
et al. (2003) by permission from American Geophysical Union.