статья в журнале

En

Sovremennye Problemy Distantsionnogo Zondirovaniya Zemli iz Kosmosa

ISSN:2070-7401
eSSN:2411-0280

2020

10.21046/2070-7401-2020-17-2-192-198

The physical limitations of the method of estimating sea depth from a pair of optical satellite images of the sea surface obtained with a time shift that is less than the period of the observed waves are considered. The method is based on the dependence of the phase velocity of surface waves on sea depth. It is shown that estimates of phase velocities in the coastal zone can be distorted as a result of reflection from the bottom slope and underwater obstacles. In cross-spectral analysis of two images, the reflected waves change the phase spectrum and, as a result, the calculated values of the phase velocities change. Depending on the amount of time shift between images, the reflected waves can lead to both an increase and a decrease in the calculated values of the phase velocities. The greatest errors in determining the phase velocity are observed in a situation when a wave travels a distance of less than 0.2 of its length over an interval equal to a time shift between images. In the presence of reflected waves, deviations of the phase velocity values calculated from optical images from theoretical values lead to the fact that different depths can correspond to the same phase velocity value.

BATHYMETRY, CROSS-SPECTRAL ANALYSIS, DISPERSION RATIO, OPTICAL SATELLITE IMAGES, REFLECTION OF SEA WAVES

2020-08-10 13:22:09