Possibilities of application of lidar methods for the discovery of oil discharge from underwater sources on the sea shelf

Abstract

This report is dealing with the problem of discovery the crude oil ( or oil products ) discharge on the sea bottom and elaboration methods for optical distant environmental control from aircraft. Application ofthe aviation methods permit to ensure the environmental monitoring ofthe sea surface and the undersurface water layers and also on shelf.The researches of characteristics of structure underwater discharge of petroleum or oil products ( OP ) is one of conditions of application of air systems ecological monitoring. The hydrophysical processes in seas cause the change of concentration and structure ofthrowing out substance. This process and interaction with processes of carry of substance by currents determines the change of structure "clouds" and conditions its detection.With the purpose of the LIDAR signal forecast and estimate it is necessary to obtain the main characteristics of oil spill in process its emerging to the sea surface. In the article 1 on the basis of theoretical analysis and experimental data it was shown that underwater oil product outburst dispersed into separate drops under influence of currents and turbulence which after that were divided into separate fractions with respect to the drop sizes and came to the sea surface as separate accumulations ( or clusters ). Every oil drops accumulation has own emerging velocity, which differed from others therefore ones are placed on various depths and that depth difference increases in process of coming to the sea surface. The drops size distribution was obtained in report 2 by comparison the fluorimeter signal tape records with oil drops velocities. This drops size distribution is shown on figure 1 . The size of oil drops varies from 0.05 to 0.75 mm and maximal quantity of drops is in range 0.4 -0.5 mm.It is possible to obtain the oil drops accumulation sizes by solving the problem of oil drops spreading from persistent source caused by current, flotation and turbulent diffusion. If origin of coordinate axes lies in the source of drops on the depth -h, xaxis is directed along current and z -axis is directed upwards to the sea surface, then it is possible to write the partial differential equation of oil drops spreading in the following way: