Blooms of blue-green algae (i.e. cyanobacteria) are temporally and spatially variable in eutrophic lakes. Algal species that constitute the blooms are also highly variable and sub-species characteristics of algae differ widely (e.g., clumping vs. non-clumping or toxin-producing vs. non-toxin producing genotypes). Because blue-green algae are often buoyant, hydrodynamic processes result in large intra-lake spatial variability in algal abundance with the potential for high inter-lake spatial correlation in bloom patterns including noxious bloom pile-ups on downwind shorelines. As a result of all these factors, the ecological and public health consequences of blue-green algal blooms can be major.
The effects of hydrologic, hydrodynamic and wind wave characteristics on environmental impacts of Madison Lakes such as bloom formation, water quality and shoreline erosion have been concerns and interests of the local authorities and Wisconsin citizens. We are developing a three-dimensional non-hydrostatic and stratified flow model (3DNHYS) to examine general circulation pattern, surface and internal waves and their breaking over shoaling bathymetry. The model would take into account of the effects of of temperature stratification, steep bathymetry, and wave-current interactions. In addition, the 3DNYHS model is coupled with a water quality model and a cohesive sediment transport model to examine the environmental impacts of LTER Lakes. Currently we are developing a nowcasting WISBIN system for the North Temperate Lakes and a Taiwan Nowcasting System for Yuan Yang Lake (TNS-YYL), selected lakes in the global ecological observatory network (GLEON).
An interdisciplinary approach will be used to characterize spatial/temporal dynamics of bloom development. For remote sensing technologies, we are currently developing a remote controlled model aircraft (DigiDot2) with a high precision CCD camera to sample across the lake. In addition, we are developing an Internet real-time video imagery with aerial photogrammetry technique for monitoring water quality in eutrophic lakes under various biophysical environment. At the lake district scale, IKONOS, QuickBird, SPOT, and Landsat will be used to study blooms on lakes. To acquire in-situ and real-time data, a state-of-the-art wireless buoy, vertical profiling buoy, and the BEDS are used to measure nutrients, phytoplankton and zooplankton species densities, velocity and temperature profiles. Molecular characterization of cyanobacterial taxa are used to detect community change in response to in-situ and remote chemical and physical measurements. Some on-going research progress can be found at the Lake Mendota Enviromental Obseveratory website. Our interdisciplinary approach permit us to assess algal bloom as the synchronicity of bloom development among lakes and the spatial variability of such external drivers as weather or climate change.
Ongoing research also addresses multiple aspects of the engineering challenge associated with discharging treated effluent to Lake Mendota. This is part of a potential strategy for solving the dual problems of managing the Yahara River watershed hydrologic budget and treated effluent from a treatment plant that may one day be constructed on the north side of Lake Mendota. The overall goal of the project is to evaluate the effects of hypolimnetic discharge. Specific tasks include: (1) the hydrodynamics of the lake; (2) fate and transport of phosphorus in the lake; and (3) the composition and phosphorus-liberating activity of the lake bacterial communities. The integrated model shows that discharge effluents would be trapped within the hyperlimnion during the summer season but could escape through the thermocline under a strorm event.
Another on-going research is the development of the Interactive Nowcast and Forecast Operation System (INFOS) that provides real-time measured and modeling water information for the Yahara Lakes. INFOS is a community online web platform that shows real-time data including water level, discharge, temperature, and other meteorological measurements. In addition INFOS also integrates observations into models to provide spatial variation of water parameters and transport of sediments and nutrients. The present stage and future stage of lake information will be posted through the web using nowcasting and forecasting models. Our overall goal is to provide managers and researchers to assess the water levels and nutrient management strategies for the Yahara Lakes system.
For Great Lakes, our project's goal
is to understand the carbon balance
of Lake Superior. This is a first attempt to close the carbon budget
for one
of the Great Lakes using numerical models and data. We aim to develop
reliable estimates of lake-atmosphere CO2 fluxes on seasonal to decadal
timescales and to identify key uncertainties in the carbon budget.
Additionally, this project will contribute to efforts led by
terrestrial
carbon cycle scientists to understand the regional carbon budget.
Currently we have developed a hydrodynamic model that is linked with
Google-earth to visualize circulation and carbon transport
(Circulation-Carbon-Google-Earth, CCGE).
We
collaborating with Galen
Mckinley and Ankur Desai
at the Department of Atmospheric and Oceanic Sciences and Noel
Urban of Michigan Technological University on this project.
Sponsor :
Arthur H. Frazier Fellowship
City of Madison, WI
Dane County Land and Water Resources Department
Gordon and Betty Moore Foundation
Madison Metropolitan Sewerage District
NSF-North Temperate Lakes Long-Term Ecological Research
NSF-Ocean Sciences
NSF-Environmental Biology
University of Wisconsin Sea Grant Institute, NOAA
Wisconsin Alumni Research Foundation
Wisconsin Coastal Management Program, NOAA
Status : Active
Student Investigators:
Yi-Fang Hsieh (Ph.D.), Jordan Read (Ph.D.), Khurran Khan (Ph.D.), John Reimer (Ph.D.)
Josh Anderson (M.S.), Sen Yan (M.S.), Hoi Lai Tseung (M.S.)
Graduated: C.C. Jay Young (Ph.D.), Nobuaki Kimura (Ph.D.), Henry Yuan (Ph.D.),
Dong Yong Choi (Ph.D.), Theresa Possley (M.S.), Chris Petykowski (M.S.),
Justin Wanek (M.S.)
Openings
Publications:
- Hsieh, Y.F. and Wu, C.H., Modeling buoyant effluent plumes
in a stratified Lake, to be submitted, 2009.
- Kimura, N., Wu, C.H., and Hoopes, J.A., Effects of spatial wind patterns and diurnal heat cycles on small, shallow lake dynamics, to be submitted, 2009.
- Yuan, H.L. and Wu, C.H., Numerical investigation of
vegetation effects on flow motions using a non-hydrostatic model with a
generic two-equation turbulence closure, to be submitted, 2009.
- Kamarainen, A., Yuan, H.L, Wu, C.H., and Carpenter, S.R., Estimates of phosphorus entrainment in Lake Mendota: A comparison of one-dimensional and three-dimensional approaches, Limnology and Oceanography: Methods. 7, 553-567, 2009..
- Hanson, P.C. Carpenter, S.R., Kimura, N., Wu, C.H., Cornelius, S.P., Kratz, T.K., Evaluation of metabolism models for free-water dissolved oxygen methods in lakes, Limnology and Oceanography: Methods, 6, 454-465, 2008.
- Carpenter, S.R., Benson, B.J., Biggs, R., Chipman, J.W., Foley, J.A. Foley, Golding, S.A., Hammer, R.B., Hanson, P.C., Johnson, P.T.J., Kamarainen,A.M., Kratz, T.K., Lathrop, R.C., McMahon, K.D., Provencher, B., Rusak, J.A., Solomon, C.T., Stanley, E.H., Turner, M.G., Vander Zanden, M.J., Wu, C.H. and Yuan, H., Understanding regional change: Comparison of two lake districts. BioScience: 57(4), 323-335, 2007.
- Yuan, H.L. and Wu, C.H., Fully non-hydrostatic modeling of surface waves, J. of Engineering Mechanics-ASCE, T132 (4), 447-456, 2006.
- Wu, C.H. and Wanek, J.M., A low-cost, ground-based, oblique, multi-spectral imaging system for chlorophyll concentration measurements, 2006..
- Choi. D.Y. and Wu, C.H., A new efficient 3D non-hydrostatic free-surface flow model for simulating water wave motions, Ocean Engineering, 33(5-6), 587-609, 2006.
- Yuan, H.L. and Wu, C.H., An implicit 3D fully non-hydrostatic model for free-surface flows, International J. for Numerical Methods in Fluids, 46, 709-733, 2004.
- Yuan, H.L. and Wu, C.H., A two-dimensional vertical non-hydrostatic model with an implicit method for free-surface flows, International J. for Numerical Methods in Fluids. 44, 811-835, 2004.
- Wu, C.H. and Yuan, H., Efficiency and Accuracy of Non-hydrostatic modeling of free-surface flows, 434-447, 9th Estuarine and Coastal Modeling, ASCE, 2006.
- Wu, C.H. and Yuan, H.L., A fully non-hydrostatic three-dimensional model with implicit algorithm, ASCE, 8th Estuarine and Coastal Modeling, ASCE, 8th Coastal and Estuarine Modeling, ISBN: 0784407347, 2004.
- Wanek, J. M., Development of digital imaging techniques for monitoring environmental processes, Master Thesis, Civil and Environmental Engineering, UW-Madison, 2004.
- Petykowski, C., Wind wave modeling and verification on small lakes, Master Thesis, Civil and Environmental Engineering, UW-Madison, 2004.
- Possley, T., A conservative, unrestricted-time-step method for a coupled multi-dimensionsal, non-hydrostatic, free-surface flow and transport model for application to the esturine environment, Master Thesis, Civil and Environmental Engineering, UW-Madison, 2003.
Lake hydrodynamics processes
Circulation
pattern in Lake Mendota
Transport of
effluent under a storm event
Lake Superior
circulation in
google-earth 
Freak wave at the Sea Cave
