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This project is no longer current. Please see the Research Programs page for a list of current research projects.
Hydrodynamic and Sediment Dynamics Modeling
Primary Investigator:
David Schwab - NOAA/GLERL
Co-Investigators:
C. Lee - National Research Council*
D. Beletsky - CILER - University of Michigan
C. Wu - University of Wisconsin*
E. Rutherford - NOAA/GLERL
D. Mason - NOAA/GLERL
M. Stein - University of Chicago*
Objectives
This project is concerned with developing and testing a numerical model for predicting resuspension, transport, and deposition of fine grained sediments in Lake Michigan. The model will provide significant insight into the mechanisms of cross-margin transport in the Great Lakes, and semi-enclosed seas. The results from the model will lead to better understanding of the response of the Great Lakes ecosystem to the impact of natural and anthropogenic stressors.
Project Rationale
Wind-driven transport is a dominant feature of circulation in the lakes. In addition to the spatial and temporal variability of the wind forcing, the earth’s rotation, basin topography, and vertical density structure are all important influences in the dynamical response of the lake. The response of an enclosed basin with a sloping bottom to a uniform wind stress often consists of longshore, downwind currents in shallow water, and a net upwind return flow in deeper water. The streamlines of the flow field form two counter-rotating closed gyres (Figure 1a), a cyclonic gyre to the right of the wind and an anticyclonic gyre to the left (in the northern hemisphere). In this classic two gyre pattern, there are two points along the shoreline where cross isobath transport occurs, one on the upwind shore where diverging longshore currents are accompanied by onshore flow, and one on the downwind shore where converging longshore currents are accompanied by offshore flow. As the wind relaxes, the two-cell streamline pattern rotates cyclonically within the basin (Fig. 1a-c.), with a characteristic period corresponding to the lowest mode vorticity wave of the basin. For a Coriolis parameter and geometry representative of the Great Lakes, this period is on the order of 3-5 days, closely corresponding to the periodicity of storm forcing. Numerical models approximating actual lake geometry have proven to be remarkably effective in explaining observed circulation patterns in lakes. Modeling exercises have shown that the actual bathymetry of each of the Great Lakes tends to act as a combination of bowl-shaped sub-basins, each of which tends to support its own two-gyre circulation pattern.
In conjunction with the wind-driven circulation pattern, storm-generated waves will tend to be highest on the downwind end of the lake, coincident with the initial location of the convergence zone. If storm waves are large enough to resuspend bottom sediments, this will also be the zone of highest water column concentration of suspended sediments. Our hypothesis is that these two hydrodynamic factors combine to generate a preferential zone of offshore transport in the southeastern part of Lake Michigan.
Figure 1. Two-gyre vorticity wave in a circular paraboloid.
Accomplishments
In 2004, Lake Michigan meteorological data for 2001-2003 were assembled, quality checked and interpolated to 2 km model grid. The hydrodynamic model was run for January 1, 2001 to December 31, 2003 period. The results were used in particle trajectory model calculations for June-August 2001-2003. As in previous biological model runs, we are testing the model for two food availability scenarios that would allow larvae to feed at a maximum rate, and half their maximum rate (P_val equals 1 and 0.5). Again, larvae were released only in one area known for yellow perch spawning between Chicago, IL and Waukegon, IL. The model run begins on day 150 (May 30) and ends on day 239 (August 27 ). Particles were released at 3 depths (surface, mid-depth, bottom) in waters less then 10 m deep (246 particles total). We are making calculations for two settlement sizes, 30 and 50 mm.
We also obtained a bioenergetics model for larval alewife and are currently testing this model before linking it with the particle trajectory model. The model will be run for a 1998-2003 period with initial sources of larval alewife near Twin Rivers, WI.
Physical limnology field studies were conducted in June-July, 2003 on Lake Michigan in support of hydrodynamic modeling efforts to estimate the trajectories of larval yellow perch. Satellite-tracked and GPS reporting drifting buoys were released in the coastal waters of southern Lake Michigan. Drifting buoys were placed in the vicinity of a known perch spawning areas. Resulting drifter trajectories are presented in Figure 2 and 3.
Figure 2. Drifter 4746 track.
Figure 3. Drifter 4791 track
The sediment dynamics modeling part of this project will be merged with N. Hawley's project on "Measurement and modeling of wave-induced sediment resuspension in nearshore water". Progress in FY04 included successful retrieval of Lake Michigan moorings and addition of data from these moorings to other time series measurements of turbidity and wave forcing for additional model validation.
Figure 4. GLERL Wave Measuring ADCP
Figure 5. Wu sediment dynamics quadrapod
Methods
Sediment dynamics
In the fall of 2002 and 2003 we deployed the two new wave-measuring ADCP’s
along with self-recording transmissometer packages at 10m and 20m depths
off of St. Joseph, MI to simultaneously measure the turbidity gradient
and associated wave and current fields. This data is crucial for testing
the validity of the new sediment dynamics model. An NRC post-doc, Cheegwan
Lee, will be comparing this data as well as other data collected during
the EEGLE program to long-term sediment model predictions.
In addition, in 2003 Chin Wu (University of Wisconsin) deployed a sophisticated
sediment dynamics instrumentation package between the GLERL moorings and
is planning to collaborate on the data analysis.
Particle Transport
A Great Lakes Fisheries Trust project (Modeling
the Influence of Lake Circulation Patterns, Upwelling Events, and Turbulence
on Fish Recruitment Variability in Lake Michigan) was initiated in
2002 to use the hydrodynamic transport model of Lake Michigan to investigate
the impacts of lake circulation on dispersal of yellow perch larvae The
model uses 3D currents generated by the Great Lakes version of the Princeton
Ocean Model driven by observed momentum and heat fluxes in June-August
1998, 1999 and 2000. Virtual larvae were released in the nearshore region
with the most abundant preferred substrate for yellow perch spawning,
rocks. We will be investigating the potential for physical transport mechanisms
to affect recruitment of Lake Michigan yellow perch by coupling the hydrodynamic
model results with individual-based particle models of fish larvae to
study variation in larval distributions, growth rates, and potential recruitment.
Advective Processes
In collaboration with M. Stein (U. Chicago Statistics Dept.) we are studying
statistical approaches to data assimilation for advective transport. These
results could be used to improve circulation model simulations based on
observed data from current meters, as well as incorporating satellite
imagery into sediment dynamics models. This year we will compare modeled
and observed currents in Lake Michigan using an autoregressive basis function
model.
Products
Beletsky, D., D. J. Schwab, 2001. Modeling circulation and thermal structure in Lake Michigan: Annual cycle and interannual variability. J. Geophys. Res 106:19745-19771.
Beletsky, D., D. J. Schwab, D. M. Mason, E. S. Rutherford, M. J. McCormick, H. A. Vanderploeg, and J. J. Janssen. Modeling the transport of larval yellow perch in Lake Michigan. Proceedings of the Estuarine and Coastal Modeling 8th International Conference, Monterey, CA, November 3-5, 2003. American Society of Civil Engineers, 439-454 pp. (2004).
Chen, C., R. Ji, D. J. Schwab, D. D. Beletsky, G.L. Fahnenstiel, M. Jiang, T. H. Johengen, H.A. Vanderploeg, B. J. Eadie, J.W. Budd, M.H. Bundy, W. Gardner, J.B. Cotner, and P.J. Lavrentyev. 2002. A model study of the coupled biological and physical dynamics in Lake Michigan. Ecol. Modeling 152:145-168
Chen, C., L. Wang, J. Qi, H. Liu, J. W. Budd, D. J. Schwab, D. Beletsky,
H. A. Vanderploeg, B. J. Eadie, T. H. Johengen, J. Cotner, and P. J. Lavrentyev.
A modeling study of benthic detritus flux's impacts on heterotrophic processes
in Lake Michigan. Journal of Geophysical Research 109(C10S11):13 (2004).
http://www.glerl.noaa.gov/pubs/fulltext/2004/20040013.pdf
Chen, C., L. Wang, R. Ji, J. W. Budd, D. J. Schwab, D. Beletsky, G.
L. Fahnenstiel, H. A. Vanderploeg, B. J. Eadie, and J. Cotner. Impacts
of suspended sediment on the ecosystem in Lake Michigan: A comparison
between the 1998 and 1999 plume events. Journal of Geophysical Research
109(C10S05):18 (2004).
http://www.glerl.noaa.gov/pubs/fulltext/2004/20040012.pdf
Eadie, B.J., D. Schwab, T. Johengen, P. Lavrentyev, G. Miller, R. Holland, G. Leshkevich, M. Lansing, N. Morehead, J. Robbins, N. Hawley, D. Edgington, and P. Van Hoof. 2002. Particle transport, nutrient cycling, and algal community structure associated with a major winter-spring sediment resuspension event in southern Lake Michigan. J. Great Lakes Res 28(3):324-337.
Hawley, N., B. M. Lesht, and D. J. Schwab. A comparison of observed and
modeled surface waves in southern Lake Michigan and the implications for
models of sediment resuspension. Journal of Geophysical Research 109(C10S03):11
(2004).
http://www.glerl.noaa.gov/pubs/fulltext/2004/20040015.pdf
Hook, T. O., E. S. Rutherford, S. J. Brines, D. J. Schwab, and M. J. McCormick. Relationship between surface water temperature and Steelhead distributions in Lake Michigan. North American Journal of Fisheries Management 24:211-221 (2004).
Ji, R., C. Chen, J.W. Budd, D.J. Schwab, D. Beletsky, G.L. Fahnenstiel, T.H. Johengen, H.A. Vanderploeg, B.J. Eadie, J.B. Cotner, W. Gardner, and M.H. Bundy. 2002. Influences of suspended sediments on the ecosystem in Lake Michigan: a 3-D coupled bio-physical modeling experiment. Ecol. Modeling 152:169-190.
Lou, J., D.J. Schwab, D. Beletsky, and N. Hawley. 2000. A model of sediment resuspension and transport dynamics in southern Lake Michigan. J. Geophys. Res 05:6591-6610.
Raudsepp, U., D. Beletsky and D.J. Schwab, 2003. Basin-scale Topographic Waves in the Gulf of Riga. J. Phys. Oceanogr. 33, 1129-1140.
Schwab, D.J., D. Beletsky, and J. Lou. 2000. The 1998 coastal turbidity plume in Lake Michigan. Estuarine, Coastal, and Shelf Science 50:49-58.
Schwab, D.J. and D. Beletsky. 2003. The relative effect of wind stress curl, topography, and stratification on large-scale circulation in Lake Michigan. J. Geophys. Res. 108(C2), 26-1:26-10.
Schwab, D.J. and D. Beletsky. 2002. Hydrodynamic and sediment transport modeling of episodic resuspension events in Lake Michigan. Proceedings of the 7th International Conference of Estuarine and Coastal Modeling, November 5-7, 2001, St. Petersburg, Florida, 266-279.
*Link leads off GLERL's website