Past projects


Research interest

My general interest is in the study of coastal ocean processes both from the observational and the modeling perspective. My interests include the study of baroclinic processes, frontal dynamics, upwelling events, and the interaction between continental shelf circulation and Western Boundary Currents such as the Gulf Stream. Some of the tools used for this work include numerical ocean models and data assimilation. This research is part of the scientific application of recently developed coastal ocean observing and prediction systems such as SEACOOS (www.seacoos.org).

SEACOOS is a collaborative university partnership that collects, manages, and disseminates integrated regional ocean observations and information products for the coasts of North Carolina, South Carolina, Georgia, and Florida (Seim et al., 2003). Funding for this effort has been provided by the Office of Naval Research.


Main research topics

Seacoos model solution

  • SEACOOS NC/FC system:
    The SEACOOS effort includes the implementation of an operational model system for nowcasting and forecasting (NC/FC) the coastal ocean. The system extends from the Virginia-North Carolina border to the Mississippi River and requires collaboration by several institutions (UNC, UM, USF). The focus in our lab is to produce forecast fields for the South Atlantic Bight (SAB) region. Close collaboration with Brian Blanton (UNC)
hycom to quoddy

  • Connectivity between basin- and shelf-scale models:
    The goal is to implement a one-way nested system that uses initial and boundary conditions from basin-scale simulations such as HYCOM (HYbrid Coordinate Ocean Model) for regional model simulations of the coastal ocean in the SAB. My role is to support the research effort by Brian Blanton.
2003 bottom temperature

  • Summer 2003 upwelling event:
    Unusually cold sea-water temperatures were observed along much of the U.S. eastern seaboard during the summer of 2003. Hydrographic and atmospheric observations from spring through summer are being analyzed to track the evolution of the cold water event and investigate links to various forcing mechanisms of this event in the SAB (Aretxabaleta et al, 2005).
    A set of model simulations is being completed to determine this principal forcing mechanisms during the cold event. Updated mass field boundary conditions from basin-scale HYCOM simulations are being tested to provide off-shore and upstream influences.

h/u3

  • Potential energy balance in the SAB:
    Controls on vertical density stratification are explored using a potential energy formulation for the SAB. The efficiency of wind and tidal mixing remains poorly understood. Wind and heat flux data is being used to evaluate spatial and temporal estimates of the work balance in the SAB. During the fall and winter, all the different forcing mechanisms combined to provide conditions favoring mixing over the entire shelf. The resulting fields suggest the presence of a front in the near-shore region around the 10-m isobath during spring and summer. The character of the SAB shelf produces large fluctuations in the position of the front with small changes in forcing.

Additional work 

As part of my dissertation (July 2005) work I will be finishing several articles extracted from the different chapters.

Baroclinic processes in coastal oceans: observations and modeling on Georges Bank and the South Atlantic Bight continental shelf

  1. Introduction
  2. Data Assimilative Hindcast on Georges Bank: Frontal Circulation and Implications  (article)
  3. Cold Event in the South Atlantic Bight During Summer of 2003: Anomalous Hydrographic and Atmospheric Conditions  (article)
  4. Tidal and Wind Mixing versus Thermal Stratification in the South Atlantic Bight (white paper)
  5. Cold Event in the South Atlantic Bight During Summer of 2003: Model Simulations and Implications   (article)
  6. Conclusions

 
 
 


Ocean Processes Numerical Modeling Laboratory

University of North Carolina at Chapel Hill
Department of Marine Sciences
   CB #3300, 12-7 Venable Hall
   Chapel Hill, NC 27599-3300
   TEL:  (919) 962-4466
   FAX:  (919) 962-1254
alfredo@email.unc.edu