The authors previously simplified their analytically complex model "JBZ" of coherent acoustic reflection loss at the ocean surface, and demonstrated that that simplified JBZ model gave loss results similar to those obtained from Monte Carlo parabolic equation (PE) modelling of equivalent scenarios. These models obtained a surface roughness loss inclusive of the refractive effects of a uniformly stratified distribution of near-surface, wind-driven bubbles. Further approximation of the simplified JBZ model has since been carried out. The approximated model, which is the subject of this paper, combines descriptions of roughness loss and bubble-refraction described for the earlier model versions, however, by restricting the ranges of wind speeds, frequencies and grazing angles, achieves an even simpler form. It is now shown that, for a limited, but useful, range of scenarios, for grazing angles as much as about 10 degrees in some cases, the coherent reflection loss at the wind-driven ocean surface, in dB, is well approximated by a function which is linear in grazing angle, where that angle is taken as the angle of acoustic incidence at the bottom of the bubbly region.
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