Alexandr Rassadin

Nizhny Novgorod State Technical University 

 

Abstract:

In present time the remote sensing of the ocean surface with the assistance of various-based, mostly the cosmic, radars and optical equipment is a typical method of oceanic studies. Internal waves are often visible on radar screens, and on the pictures, taken from satellites, as they cause currents near the surface, that influence on the characteristics of surface waves (wind ripple). So, various surfactants, as well as other floating on the ocean surface objects (a solid ice or a pancake ice) are gathering in convergence zones of local surface currents, caused by internal waves, and in areas of divergence – discharges. Transformation process of the internal waves in conditions of the real ocean is very difficult, since the environment properties are inhomogeneous, anisotropic and changes over time. Additional complication is that for real ocean stratification, a dispersion relation for the internal waves does not have an explicit analytical expression and looks from solut!

ion of the boundary value problem. In this work we studied the transformation of nonlinear internal waves in the ocean with a depth and a hydrology, variable in the space, in the framework of the Gardner beam equation. Special attention is paid to the peculiarities of the evolution and transformation of strongly non-linear waves in various combinations of the parameters of the field of internal waves and external factors. All the numerical calculations were carried out in a new version of the program complex IGW RESEARCH, intended for numerical simulation of diffusion and the transformation of the internal gravity waves in the world ocean, with completed block for calculating the amplitude of the internal wave along the beam and differential width of ray tube. The developed software complex is universal, timely, relevant and the only one of its kind in this class of geophysical problems.