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dc.contributor.authorDorostkar, Abbas
dc.contributor.otherQueen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.))en
dc.date2012-12-14 12:45:21.727en
dc.date.accessioned2012-12-14T19:17:19Z
dc.date.available2012-12-14T19:17:19Z
dc.date.issued2012-12-14
dc.identifier.urihttp://hdl.handle.net/1974/7693
dc.descriptionThesis (Ph.D, Civil Engineering) -- Queen's University, 2012-12-14 12:45:21.727en
dc.description.abstractThe three-dimensional (3D) baroclinic response of Cayuga Lake to surface wind forcing was investigated using the fully nonhydrostatic MITgcm. The model was validated against observed temperature data using a hydrostatic 450 m (horizontal) grid and both qualitative and quantitative methods. The model correctly reproduces the basin-scale dynamics (e.g., seiche with horizontal mode-one period T1 = 80 h) with a basin-wide root-mean-square error of 1.9 C. Nonlinear internal surges were visualized to evolve due to (i) a wind-induced locally downwelled thermocline (wind duration Twind < T1/4), (ii) a basin-scale wind-induced upwelled thermocline (Twind > T1/4), (iii) internal hydraulic jumps (IHJs). Results from a 113 m grid and field observations were used to characterize the basin-scale internal wave field according to composite Froude number (G2), Wedderburn number (WN), and Lake number (LN). The typical Cayuga Lake response is a surge when ~ 1 < WN (LN) < ~ 2-12 and a surge with emergent nonlinear internal waves (NLIWs) when WN or LN < ~ 2, in agreement with published laboratory studies. An observed shock front was simulated to be an IHJ, occurring at mid-basin during strong winds when WN < 0.8. This is the first simulation of a mid-basin seiche-induced IHJ due to super critical conditions (G2 > 1) in a lake. The topographic-induced IHJs were also shown to form when the surges interact with a sill-contraction topographic feature. Both high-resolution hydrostatic and nonhydrostatic models were used to investigate the evolution, propagation and shoaling of NLIWs at medium lake-scale. A nonhydrostatic 22 m grid with lepticity λ ~ 1 ensures minimal numerical relative to physical dispersion, qualitatively reproducing observed dispersive NLIWs using ~ 2.3E+8 grid cells. Solitary waves evolve with almost unchanged wavelengths upon grid refinement from 40 m (λ ~ 2) to 22 m; suggesting model convergence to the correct solution. Corresponding hydrostatic grids were shown to produce a packet of narrower spurious solitary-like motions with different wavelengths, representing a balance between nonlinear steepening and numerical dispersion. Local gyre-like patterns and secondary transverse NLIW packets were visualized to result from wave-topography interaction, suggesting that NLIW propagation in long narrow lakes, where the bottom topography has irregularities is fundamentally 3D.en_US
dc.languageenen
dc.language.isoenen_US
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectInternal surgeen_US
dc.subjectNonhydrostaticen_US
dc.subjectBaroclinicen_US
dc.subjectInternal hydraulic jumpen_US
dc.subjectGrid leptic ratioen_US
dc.subjectLong narrow lakeen_US
dc.subjectWedderburn numberen_US
dc.subjectLake numberen_US
dc.subjectSimulationen_US
dc.subjectMITgcmen_US
dc.titleThree-Dimensional Dynamics of Nonlinear Internal Wavesen_US
dc.typeThesisen_US
dc.description.degreePh.Den
dc.contributor.supervisorPollard, Andrewen
dc.contributor.supervisorBoegman, Leonen
dc.contributor.departmentCivil Engineeringen


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