Scattering of long waves at the estuaries bordering on a continental shelf. II.

Abstract

Leaking energies of long waves from a rectangular bay bordering on a straight band of shallow water which in turn borders on deep water are evaluated under some specifications of the ratio of the to bay widths B/2 and the depth ratio R. The effects of the width and depth ratio upon the leaking energy are then examined. Using the same model as that used in the evaluation of the leaking energy, the transmissity of edge waves through a rectangular concave irreg-ularity is elucidated under the specifications of B=1 and R=5 allowing for the application of the results to the geometry of the coast and continental on the southeast side of Hokkaido in Japan. The important features exposed are the significant effects of the bay, and bay-shelf resonances upon the transmission of edge waves. On the occurrence of a longitudinal bay resonance the energy scattered is directed primarily towards the deep water with a small contribution to the generated edge waves, while in the case of the occurrence of a higher mode bay resonance the energy scattered around the bay entrance contributes primarily to the generated edge waves. In addition to the outstanding effect of the bay resonance, the bay-shelf reso-nance which occurs through the bay and continental has a considerable influence upon the scattering of energy in such a way that the scattered energy into the deep water is highly excited at the points corresponding to the resonance of the normal plane leaky mode on the supposed continental shelf with the width of the sum of the bay length and the width of the stretching along the deep water.