AOS Faculty Profile
Sonya Legg
Lecturer, Ph.D. Imperial College, University of London
Address: 352 GFDL
Phone: (609) 452-6582
Email: Sonya.Legg at noaa.gov
Ocean Turbulence and Mixing
Turbulent mixing processes in the ocean occur on small-scales, yet play an important role in the large-scale climate circulation of the ocean. Examples include oceanic deep convection, mixing driven by tides flowing over the topography of the sea-floor, and the mixing in dense currents flowing down the continental slopes. Because climate models use grids on scales of the order of 100km, they are unable to capture these small-scale processes, and the net effects of the small-scale mixing - for example the modifications of the large-scale temperature and salinity fields - must be parameterized. My research focuses on obtaining a better understanding of these small-scale processes through high resolution numerical simulations combined with theoretical analysis, and using this understanding to derive new physically-based parameterizations to help improve climate simulations.
Some Recent Publications:
Legg, Sonya, and J Klymak, September 2008: Internal hydraulic jumps and overturning generated by tidal flow over a tall steep ridge. Journal of Physical Oceanography, 38(9), doi:10.1175/2008JPO3777.1
Jackson, L, Robert W Hallberg , and Sonya Legg , May 2008: A Parameterization of shear-driven turbulence for ocean climate models. Journal of Physical Oceanography, 38(5), doi:10.1175/2007JPO3779.1
Legg, Sonya , Tal Ezer, Stephen Griffies , Robert W Hallberg , and L Jackson, et al., May 2009: Improving oceanic overflow representation in climate models: The gravity current entrainment climate process team. Bulletin of the American Meteorological Society, 90(5), doi:10.1175/2008BAMS2667.1
Klymak, J, and Sonya Legg , April 2010: A simple mixing scheme for models that resolve breaking internal waves. Ocean Modelling, 33(3-4), doi:10.1016/j.ocemod.2010.02.005