The Disintegration (or not) of the Nonlinear Internal Tide

Abstract

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching data sources. gathering and maintaining the data needed, and completing and reviewing the collection of information. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)Elizabeth Ford, ONR BD252 Office of Naval Research 875 North Randolph Street Arlington, VA 22203-1995 SPONSOR/MONITOR'S ACRONYM(S) SPONSORING/MONITORING AGENCY REPORT NUMBER ONR DISTRIBUTION AVAILABILITY STATEMENTunlimited, unclassified SUPPLEMENTARY NOTES ABSTRACTSatellite and in situ observation demonstrate that the large, nonlinear internal waves found in the northeastern basin of the South China Sea arise from the nonlinear steepening of the internal tide as it propagates westward from the generation region in the Luzon Strait. This research is aimed at understanding the role of rotation in the evolution of the internal tide and the emergence of nonlinear internal waves from the tide. Theoretical and numerical models have been developed and applied to both the evolution of the tide, where it is found that rotation can inhibit the disintegration, and to the evolution of individual solitary waves, where it is found that a solitary wave will decay by radiation damping to form nonlinear wave packets. Additional research on wave generation by gravity currents and flow through straits, and models of large-amplitude solitary waves with trapped cores has been undertaken. This research is part of the South China Sea NLIWI DRI.