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Hui Wu

, termed the β drift, plays the role of shoreward advection speed due to the propagation of the planetary Rossby wave. The β drift D β is the ratio between planetary and topographic Rossby wave speeds. It suggests that the planetary β can be important on shelves with small s . Equation (11) is subjected to following “initial” and boundary conditions: (12) η ⁡ ( x , 0 ) = η 0 ⁡ ( x ) , (13) η ⁡ ( B , y ) = η B ⁡ ( y ) , (14) α η x ⁡ ( 0 , y ) + η y ⁡ ( 0 , y ) = 0 . The quotation mark means

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Hemantha W. Wijesekera, Joel C. Wesson, David W. Wang, William J. Teague, and Z. R. Hallock

bottom boundary through intense turbulent mixing. Furthermore, the region is associated with high vertical transports resulting from flow convergences and diapycnal transports due to energetic mixing in the thermocline. These small-scale to mesoscale vertical transports are 100–1000 times larger than for the typical open-ocean conditions. Acknowledgments This work was sponsored by the ONR Grant N0001416WX01186. Special thanks to Mr. Andrew Quaid and Mr. Ian Martens for their efforts and their

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Shuwen Tan, Larry J. Pratt, Dongliang Yuan, Xiang Li, Zheng Wang, Yao Li, Corry Corvianawatie, Dewi Surinati, Asep S. Budiman, and Ahmad Bayhaqi

–temperature–depth (CTD) measurements recently collected along the axis of the overflow as well as 17 months of ADCP velocity data collected with a mooring deployed during 2005–06. This study will evaluate the hydraulics, mixing, and entrainment in the Lifamatola Passage. The CTD and mooring data are described in section 2 . In section 3 , the conditions for hydraulic control are assessed using the mooring data, and it is argued that the control is, in fact, present. Based on this finding, we predict volume fluxes

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Gunnar Voet, Matthew H. Alford, Jennifer A. MacKinnon, and Jonathan D. Nash

breaking near the generation sites during certain phases of the tide. In addition to shear-driven mixing processes, these waves exhibit convective breaking mechanisms in transient features associated with critical flow conditions. Depending on the tidal excursion length scale in relation to the topographic length scale, a tidal wave may reach a quasi-steady state during certain phases of the tide ( Musgrave et al. 2016 ), thus bridging the gap between tidal oscillatory waves and steady lee waves. Here

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Madeleine M. Hamann, Matthew H. Alford, Andrew J. Lucas, Amy F. Waterhouse, and Gunnar Voet

). These modes are the solutions to the equation (5) ∂ 2 ∂ z 2   η ⁡ ( z ) + N 2 ⁡ ( z ) c n 2   η ⁡ ( z ) = 0 , with boundary conditions η (0) = η ( H ) = 0, and where n is mode number, c n is eigenspeed, and H is water depth. The eigenspeed c n is the geometric mean of the phase speed c n and group speed c g , c n 2 = c g c p ( Alford and Zhao 2007b ). This method is applied to obtain the first five vertical modes for u , υ , and η , after which HKE, APE, and F are computed for

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Frederick T. Mayer and Oliver B. Fringer

wave drag. In section 4 we analyze the temporal evolution of a subset of subcritical and supercritical simulations. In section 5 we evaluate the steady-state drag and LOTS measured in all of the simulations. And in section 6 we conclude with recommendations for nonhydrostatic and time-dependent corrections to saturation theory. 2. Linear theory and parameter space As in Mayer and Fringer (2017) , we assume a nonrotating ocean with a free-slip bottom boundary condition and an infinite depth

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Kristin L. Zeiden, Jennifer A. MacKinnon, Matthew H. Alford, Daniel L. Rudnick, Gunnar Voet, and Hemantha Wijesekera

, where flow separation has been observed ( MacKinnon et al. 2019 ; Wijesekera et al. 2020 ). The high temporal resolution of the data enables quantification of vorticity on time scales of hours to months, and insight into the physical processes of wake generation due to broadband flows. The classic paradigm for vorticity wakes is a circular cylinder in steady, unidirectional flow ( Kundu and Cohen 1990 ). Vorticity is generated by a no-slip boundary condition and flow separation leads to

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Magdalena Andres, Ruth C. Musgrave, Daniel L. Rudnick, Kristin L. Zeiden, Thomas Peacock, and Jae-Hun Park

needed to help elucidate processes and ground truth numerical models. Here we use satellite altimetry together with in situ data to examine SSH variability at time scales ranging from tidal to interannual near Palau, an island group at the southern end of the Kyushu–Palau Ridge in the western North Pacific ( Fig. 1 ), which sits near the boundary between the westward-flowing North Equatorial Current (NEC) and the eastward-flowing North Equatorial Countercurrent (NECC). We use the observations to

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Kristin L. Zeiden, Daniel L. Rudnick, and Jennifer A. MacKinnon

1. Introduction Island wakes may be a significant sink of momentum for ocean currents and a source of vorticity in the interior, thus transforming incident currents. Islands in the path of energetic flows are often observed to have leeward flow reversals that are associated with the separation of a topographic boundary current ( Heywood et al. 1990 ). This recirculation may detach in the form of wake eddies, which can transport trapped water mass properties and vorticity up to hundreds of

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Eric Kunze and Ren-Chieh Lien

are most effective as a dissipative sink for balanced flow in the high-latitude abyss such as the Antarctic Circumpolar Currents in the Southern Ocean, even there they are only ~0.5 effective. This assumes (i) a linearized bottom boundary condition (7) with (ii) the minimum of the topographic spectrum (12) or saturated topographic spectrum (13) , which is discussed further in section 4 , (iii) | U | decreases with height above bottom consistent with the conditions for suppression of

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