passive acoustic monitoring for tidal energy projects
DESCRIPTION
Passive Acoustic Monitoring for Tidal Energy Projects. Brian Polagye , Chris Bassett, and Jim Thomson University of Washington Northwest National Marine Renewable Energy Center. Ecological and Environmental Monitoring April 7, 2011. Evaluating Acoustic Effects. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/1.jpg)
NNMREC
Passive Acoustic Monitoring for Tidal Energy Projects
Brian Polagye, Chris Bassett, and Jim ThomsonUniversity of Washington
Northwest National Marine Renewable Energy Center
Ecological and Environmental MonitoringApril 7, 2011
![Page 2: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/2.jpg)
NNMREC
Evaluating Acoustic EffectsMarine Mammal Behavioral
Response to Sound
Sound Received by Marine Mammal Individual Life HistoryContext for Received
Sound
Sound generated by turbine
Site-specific sound propagation
Marine mammal hearing sensitivity
Ambient noise from other sources
Marine mammal activity state
Exposure to similar sounds
![Page 3: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/3.jpg)
NNMREC
Quantifying Sound from Turbines
Common spectral peaks
(100 Hz – 3 kHz)
AHD at fish farm
Bedload transport
Nearby shipping
Data collected by Scottish Association of Marine Sciences
OpenHydro turbine (6 m diameter)
Drifting EARs data collection
Compare drift series to identify turbine-specific features
![Page 4: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/4.jpg)
NNMREC
Marine Mammal Hearing Sensitivity
Southall et al. (2007) Marine mammal exposure criteria
fRfRfM
maxlog20 10
2222
22
lowhigh
high
ffffff
fR
Turbine Noise
![Page 5: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/5.jpg)
NNMREC
Implication for Received Levels
Broadband Levels Mid-frequency Cetaceans
4x reduction in area ensonified to 120 dB
![Page 6: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/6.jpg)
NNMREC
Stationary Hydrophone MeasurementsLoggerhead DSG
Autonomous hydrophone (32 GB capacity)
80 kHz sampling 2% duty cycle for 3 months
![Page 7: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/7.jpg)
NNMREC
Temporal and Spatial Variability
Cumulative Probability Density
Hydrophone Deployments
Temporal variability dominates over spatial variability
![Page 8: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/8.jpg)
NNMREC
Vessel Traffic Monitoring with AIS
Automatic Identification System (AIS) transponders required on all vessels greater than 300 tonnes gross weight and passenger vessels
Continuous data collection and archiving
![Page 9: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/9.jpg)
NNMREC
Data Assimilation
SPL (
dB re
1 μ
Pa)
Distance to closest vessel (km)
Vessel Proximity Noise Correlation
Vessel noise drives broadband noise levels
Source: Chris Bassett, forthcoming PhD dissertation
![Page 10: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/10.jpg)
NNMREC
Implication for Evaluating Noise Effects
![Page 11: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/11.jpg)
NNMREC
Sound during High Currents
Hydrophone Response
Current Velocity
![Page 12: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/12.jpg)
NNMREC
Flow Shield Experiment
Hydrophonewith Flow Shield
Unshielded Hydrophone
Doppler VelocimeterSample volume aligned with
hydrophone element
High Velocity Region
Quiescent Region
High Porosity Foam
Hydrophone Element
Hydrophone Pressure Case
Source: Chris Bassett, forthcoming PhD dissertation
![Page 13: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/13.jpg)
NNMREC
Pseudo-Sound Identification
Unshielded Hydrophone
Hydrophone with
Flow Shield
Source: Chris Bassett, forthcoming PhD dissertation
![Page 14: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/14.jpg)
NNMREC
Propagating Sound during High Currents Bedload transport
― Elevated noise at 5-50 kHz― Consistent with size of gravel and shell hash
observed during ROV surveys; O(1 cm)
Turbulent flow over rough surfaces― Potential contribution from advected turbulence― Cannot measure velocity fluctuations directly at
frequencies of interest (e.g., > 300 Hz)
88.0
209D
f (Hz) (Thorne, 1986)
Source: Chris Bassett, forthcoming PhD dissertation
![Page 15: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/15.jpg)
NNMREC
Measuring Noise from Tidal TurbinesParameter Stationary
HydrophoneDrifting Hydrophone
Pseudo-Noise Filtering Physical shield Inherent filteringMeasurement Duration Months HoursDeployment Depth Seabed or
Turbine frameVariable (easiest near surface)
Spatial Resolution Low HighTemporal Resolution High Low
Long-term, low-intensity monitoring
Short-term, spatial characterization
![Page 16: Passive Acoustic Monitoring for Tidal Energy Projects](https://reader038.vdocuments.mx/reader038/viewer/2022103102/56815e0e550346895dcc6e84/html5/thumbnails/16.jpg)
NNMREC
Thank YouThis material is based upon work supported
by the Department of Energy and Snohomish County PUD under Award
Number DE-0002654.
Joe Talbert for keeping all equipment in working order.
Sam Gooch, Joe Graber, and Alex DeKlerk for helping turn around instrumentation.
Captains Andy Reay-Ellers for piloting skills during instrumentation deployment.