Physical Oceanography Lunchtime Seminar, Winter 2013
12:30 Wednesdays, OSB 425.
Seminar organizer: Matthew Alford, malford (at) uw.edu, 221-3257.
To add your name to the announcement list, please visit https://mailman1.u.washington.edu/mailman/listinfo/phys_ocean_seminars.
|Jan 9||Gunnar Voet||APL/UW||Flow, mixing and hydraulics in the Samoan Passage|
|Jan 16||Cimarron Wortham||MIT||Space-time scales of low-frequency ocean variability|
|Jan 23||NO SEMINAR|
|Jan 30||Jacob Wenegrat||UW||Masters defense: Near-surface Shear Flow on the Equator|
|Feb 6||Hayler Dosser||UW||Properties of Near-Inertial Waves in the Arctic Ocean from Year-Round Observations|
|Feb 13||Torge Martin||APL/UW||Southern Ocean forced multi-centennial climate variability and global impacts||Self-sustained oscillations of open ocean deep convection in the Southern Ocean drive a multi–centennial mode of climate variability in the Kiel Climate Model (KCM). The simulated deep convection in the Atlantic Sector of the Southern Ocean has intriguing similarities with the Weddell Polynya observed in the 1970s. The model shows how the competing roles of mid to deep ocean warming and surface freshening in forcing local buoyancy changes can cause global climate variations on a centennial timescale. These can be seen in global surface air temperature, Southern Hemisphere sea ice coverage, Southern Ocean and North Atlantic sea surface height, the Antarctic Circumpolar Current and the Atlantic Meridional Overturning Circulation (AMOC). Because of their magnitude the associated climate variations have the potential to locally mask global warming signals. In this presentation I will explain the mechanism behind the convection flip-flop and how it impacts the AMOC.|
|Feb 20||Jonathan Nash||OSU||The Unpredictable Nature of Internal Tides in the Coastal Ocean|
|Feb 27||Beth Scott||U. of Aberdeen||Marine renewable energy extraction, climate change and trophic linkages: What do we need to understand?|
|Mar 6||Kathleen Dohan||ESR||20 year trends in OSCAR surface currents|
|Mar 13||Jody Klymak||U. Victoria||Observational Examples of Submesoscale Lateral Mixing|
|TUES Mar 19 3:30 [SPECIALDATE/TIME]||Matthew Hecht||Los Alamos National Laboratories||Response of Atlantic Circulation to Freshwater Perturbations in a Strongly Eddying Ocean Model|
|Mar 20||Brian White||UNC Chapel Hill||Mass and energy exchange at coastal density fronts: mixing layers, gravity currents, and internal waves||In stratified coastal waters, large horizontal density gradients are common. These horizontal gradients result in propagating density fronts, which produce vertical shear, turbulent mixing, and can even generate large amplitude internal waves. In this talk two specific examples of flows with horizontal density gradients are discussed. The first is a buoyant plume propagating into stratification, which under certain conditions undergoes a resonant interaction with internal waves at the plume front. This resonance can produce large waves that develop overturning circulation and contain mixed fluid. The second case involves the mixing of two water masses with large horizontal shear and horizontal density gradient. An example is tidal flow which separates at the boundary of an island wake. In this case, vertical vorticity due to the horizontal shear tilts under gravity, is stretched and intensified, and produces large vertical mixing. These examples are explored through a combination of Boussinesq Navier-Stokes simulations, laboratory experiments, and theory, with a focus on scaling, evolution of energy budgets, turbulent mixing, and hydraulic theory for stratified fluids.|