Investigation of the influence of spectral sounding parameters in ocean exploration taking into account the agitated surface using the Monte Carlo method.

In this paper, the dependence of the probing results on the radiation spectrum of a laser source is investigated. The problem of estimating the time distribution function of the intensity of laser radiation entering the receiver after passing through the ocean-atmosphere media system from a given source, taking into account the agitated surface, is considered. 

In this paper, we consider an algorithm of Monte Carlo methods designed to solve problems of laser sensing of natural environments with a random interface. In this case, this is the surface of the sea waves when probing the ocean-atmosphere media system. The laser sensing problems under consideration differ from many other atmospheric optics problems by the presence of complex boundary conditions associated with the finite size of the initial radiation beam and the small phase volume of the detector, as well as the fundamentally non-stationary nature of the simulated radiation transfer process. This circumstance determines the characteristic requirements for statistical modeling techniques and determines the need to use local estimates, which, although time-consuming, are the only possible way to calculate the desired radiation characteristics detected by a detector with a small phase volume. 

Research shows that the results of sounding depend on the surface of the wave, which, in turn, depends on the wind speed. In this paper, the dependence of the results on the wavelength of the radiation, which affects the scattering indicatrix and, consequently, the direction of the scattered particles, was investigated. 

The ocean-atmosphere system is considered, in which, at an altitude of h, there is a random interface between two media, in interaction with which light experiences refraction or reflection. This boundary is a random surface composed of a set of elementary pads, the centers of which lie at a height of h, and the normals to the pads of s are random unit vectors with a distribution density of p(x) (for such a model of an excited surface, the name "facet model" has been approved in the relevant literature. The interaction of light with matter is determined by setting the attenuation and scattering coefficients, as well as the scattering indicatrix. In this paper, the effect of the selected indicatrix on the time distribution of the radiation intensity fixed in the detector was investigated. The question of the magnitude of the influence of wind speed on the distribution of radiation intensity at a specific wavelength was also of interest.

The simulation results showed that wind speed has an equally strong effect on the result, regardless of the indicator. Dependence graphs for different wind speeds are presented. In addition, the time distribution of intensity itself is also weakly dependent on the indicatrix. Graphs of the dependence of the intensity distribution at different wavelengths for different wind speeds, for the blue, green, and violet regions of the spectrum are presented. Preference may need to be given to wavelengths with a smoother distribution function.

The work was carried out within the framework of the state assignment of the Institute of Physics and Technology of the Siberian Branch of the Russian Academy of Sciences (project FWNM-2025-0002).