摘要
It is demonstrated that offshore wavenumbers of edge waves change from imaginary wavenumbers in deep water to real wavenumbers in shallow water. This finding indicates that edge waves in the offshore direction exist as evanescent waves in deep water and as propagating waves in shallow water. Since evanescent waves can stably exist in a limited region while propagating waves cannot, energy should be released from nearshore regions. In the present study, the instability region is predicted based on both the full water wave solution and the shallow-water wave approximation.
It is demonstrated that offshore wavenumbers of edge waves change from imaginary wavenumbers in deep water to real wavenumbers in shallow water. This finding indicates that edge waves in the offshore direction exist as evanescent waves in deep water and as propagating waves in shallow water. Since evanescent waves can stably exist in a limited region while propagating waves cannot, energy should be released from nearshore regions. In the present study, the instability region is predicted based on both the full water wave solution and the shallow-water wave approximation.
基金
financially supported by the National Natural Science Foundation of China (Grant No. 51209081)
China Postdoctoral Science Foundation (Grant No. 2012M511191)
the Qinglan Project and 333 Project of Jiangsu Province (Grant No. BRA2012130)
the National Key Basic Research Development Program of China (973 Program, Grant No. 2010CB429002)
the 111 Project (Grant No. B12032)
the Basic Research Funds for the Central Universities (Hohai University 2012B06514)
