Thermal blooming effect of laser beams propagating through seawater

The thermal blooming effect of laser beams propagating through seawater is studied in detail by using the numerical simulation method. It is found that an increase of the salinity in the seawater causes the more severe thermal blooming. As compared with the wavelength, the absorption coefficient is the main factor that dominates the thermal blooming because the absorption coefficient is very high in the seawater. In the seawater the thermal blooming becomes more severe for the wavelength corresponding to the higher absorption coefficient. Furthermore, both the behavior of the thermal blooming effect and the main factor dominating the thermal blooming effect in the shallow sea region are different from those in the deep sea region. In the shallow sea region, the dependence of the thermal blooming on the depth is not monotonic as the time increases. However, in the deep sea region, the thermal blooming effect becomes more severe monotonously as the depth increases. The physical explanations for the main results obtained in this paper are presented.