A Circulation Model to Investigate the A Circulation Model to Investigate the Movement of Wastes from an Open Ocean Movement of Wastes from an Open Ocean

Aquaculture SiteAquaculture Site

David W. FredrikssonU. S. Naval Academy

NOAA Research - Marine Aquaculture Program Grant # NA08OAR4170859

James D. IrishUniversity of New Hampshire

Dale A. KieferUniversity of Southern California

Jack RenselRensel Associates Aquatic Sciences

Frank O’brienSystem Science Applications

ObjectivesObjectives

1. Build hydrodynamic model mesh – perform calculations driving system with diurnal and semi-diurnal tides

2. Validate model hydrodynamics with measured velocities

3. Drive the AquaModel (simulates bio-energetics and the fate of wastes)

4. Preliminary case studies – goal to “Quantify Effects of Commercial Offshore Aquaculture” viewed in Google Earth

1. Develop a validated, simple to use regional circulation model of coastal MA, NH, ME (USA).

2. Use the hydrodynamic output to drive a bio-energetic and fish farm waste model

ApproachApproach

Hydrodynamic ModelHydrodynamic Model

1. Advanced Circulation Model – ADCIRC: Standard “off-the-shelf” depth averaged hydrodynamic model (with variations)

2. Solves shallow water wave equations – suitable for coastal applications – requires bathymetry and boundary conditions

3. Used by: U.S. Army Corps FEMA Navy NOAA Just about everyone else

4. Techniques can be taught to STEM* majors

5. Validation is the difficult part of modeling!

* Educational buzz-word for Science, Technology, Engineering and Math

Modeling and Data Collection SiteModeling and Data Collection Site

University of New Hampshire Open Ocean Aquaculture Site within the model domain

Boundaries and Boundaries and BathymetryBathymetry

Open Ocean

Shoreline

Island

Bathymetry: National Ocean Service Database (NOSDB)

Mesh GenerationMesh Generation

Aquaculture Site

1.Unstructured Mesh (triangular elements)

2.Interpolated Bathymetry

3.High Resolution at aquaculture site (~50 m)

Apply tide elevations and phases at open boundaries

Hydrodynamic ModelingHydrodynamic Modeling“Forcing” by tidal elevations

1. Model was “Forced” by tidal elevations at the open boundaries

2. Tidal elevations produced from the K1, O1, M2 and N2 constituents (no weather components) – low flow condition?

3. Constituent amplitudes and phases with nodal factors interpolated from database EASTCOAST 2001 for the open ocean boundaries

4. NOAA data for the Portsmouth boundary

Simulation VideoSimulation Video

Portsmouth, NH Harbor

Isles of Shoals

Aquaculture Site

Oceanographic Buoy at the Aquaculture site

Hydrodynamic ModelingHydrodynamic ModelingComparison with measured data

Pressure Sensor measures surface elevation

ADCP measures velocities

WARNING !!!!WARNING !!!!

The next The next THREE THREE

slides showsslides shows

DATADATA

Data Comparison – Aquaculture SiteData Comparison – Aquaculture SiteModel vs. Measured Surface Elevation

Data Comparison – Aquaculture SiteData Comparison – Aquaculture SiteModel vs. Measured Velocities

Data Comparison – Aquaculture SiteData Comparison – Aquaculture SiteModel vs. Measured Velocities

AquaModelAquaModel

1. AquaModel: Simulates waste deposition, benthic dynamics, water quality and bio-energetics

2. Like the hydrodynamic model results, operated within the EASy GIS program.

3. In this case, used the output of the circulation model as input to AquaModel

4. Results can be view in a Google-Earth environment

AquaModel – UNH site exampleAquaModel – UNH site example

• 12 Net Pens12 Net Pens• Pen volume: 37500 mPen volume: 37500 m33

• stocked at 15 kg/mstocked at 15 kg/m33

Portsmouth, NH

Isles of Shoals

AquaModel - SettingsAquaModel - Settings

Net PenNet PenConfigurationsConfigurations

and and Stocking DensityStocking Density

AquaModel - SettingsAquaModel - Settings

Ambient Water Ambient Water ConditionsConditions

OperationalOperationalSettingsSettings

AquaModel - SettingsAquaModel - Settings

Benthic Benthic ConditionsConditions

Hydrodynamic Hydrodynamic and and

AquaModel AquaModel results results

Presented Google EarthPresented Google Earth

Hydrodynamic and AquaModel results in Hydrodynamic and AquaModel results in Google EarthGoogle Earth

Fish Fish Farm Farm DataData

Site

Oxygen Profile

Oxygen Transect

NitrogenProfile

NitrogenTransect

SedimentCharacteristics

Hydrodynamic and AquaModel results in Hydrodynamic and AquaModel results in Google EarthGoogle Earth

Aquaculture Site: • Velocity Vectors• Fish cages• Surface Oxygen

Portsmouth, NH Harbor

Isles of Shoals

What have we done?What have we done?

1. Refine hydrodynamics – develop 3-D structure in water column2. Develop details input to AquaModel3. Investigate “carrying” capacity of the offshore site

HOW MUCH BIO-MASS CAN BE RAISED AND AT WHAT CONDITIONS

INVESTIGATE ECONOMICS OF SCALE WHILE MINIMIZING IMPACT

What are our next steps?What are our next steps?

Integrated GIS to show hydrodynamic calculations Integrated GIS to show hydrodynamic calculations driving a fish farm bio-energetic and waste modeldriving a fish farm bio-energetic and waste model

PRESENTED IN GOOGLE EARTHPRESENTED IN GOOGLE EARTH

GO NAVYGO NAVY