Water Quality/Biogeochemistry and Nearshore Sensors

Eric H. De Carlo

Margaret A. McManus

Geno Pawlak

Grieg Steward

Objectives of WQ/Sensor Component

• To develop and implement integrated real-time nearshore water property (quality) monitoring systems

• To provide government agencies and the public with timely WQ information for decision making wrt health and safety in the nearshore aquatic environment

• To provide researchers with high-quality time-series data that will enhance understanding of the response of the coastal ocean to natural and anthropogenic forcing

The economic well-being of the State of Hawaii depends upon healthy coastal ecosystems

• Public confidence in water quality and safety is crucial

• Many current monitoring approaches are labor intensive and slow

• An integrated coastal sensor/ocean observing system will:

• Boost public confidence by emphasizing the usual high quality of Hawaii’s waters

• Contribute to public safety by providing early warning of water quality problems and forecasting areas likely to be affected

Floodwaters in Ala Wai CanalFloodwaters in Ala Wai CanalManual monitoring for Manual monitoring for pathogens is slowpathogens is slow

CRIMP - Kaneohe BayCRIMP - Kaneohe Bay

Kilo Nalu - KakaakoKilo Nalu - Kakaako

Automated ocean observing platforms existAutomated ocean observing platforms existVibrio vulnificus

Principal HIOOS WQ Assets• Two buoys (Offshore Kaka`ako and Magic Island/Ala Wai)

– Seabird sensor packages for salinity, temperature, dissolved oxygen, turbidity and chlorophyll-a at 20 min frequency (deployed in first year)

– Nitrate sensors (to be deployed in second year)– Satlantic telemetry by cell phone to UH system– CO2 /O2 measuring system (3 hr intervals with Iridium telemetry to NOAA/PMEL)

• Four “nearshore sensor” (NS) stations:– Seabird sensor packages as above (less oxygen)– Cell phone telemetry– Two systems implemented in year 1 in Ala Wai channel– Two systems implemented in year 2: Locations to be determined– Complemented by ADCP (from industry partnership)

• REMUS AUV surveys:– Event driven surveys

• Automated Water sampler (to be deployed in year 2):– Collects water samples upon “triggering” by sensors or remote access– Provide samples for laboratory based analyses (e.g., bio, microbes)– Samples backed by sensor data at time of collection

Buoy and Sensor Locations

Buoys and Sensors• SBE 16+ SEACAT® C-T

(salinity, temperature)

• SBE-43 (Dissolved Oxygen)

• FLNTU (turbidity, fluorescence)

• Space for sensor development

• Telemetry (cellular)

AUV Water Quality SurveysAutonomous Underwater Vehicle (AUV): REMUS• Conductivity (salinity), temperature, flow velocity, fluorescence (Chl-a),

2 freq. optical backscatter, acoustic backscatter, bathymetry, bed morphology (sidescan sonar)

• 8 hour surveys (5 kts): 70 km

• 20 hour surveys (3 kts): >100 km

• Event based surveys: (3 per year)Provide distributions, spatial gradients in water properties during-after “events” (identified by sensor network ‘flag’ or by users)

• Regular surveys: Bimonthly (6 per year)Spatial data on baseline water properties; provide spatial ‘context’ for nearshore/offshore sensor network, water sampling programs

AUV Water Quality Surveys

WQ Products• Time series water quality data:

– Salinity, Temperature, DO, Chl-a, Turbidity, Nitrate– Data from two CRIMP-CO2 type buoys and two/four nearshore moorings– Use of WQ data to identify ‘events’ that trigger AUV surveys and other sampling

efforts.

• Near real time plots of WQ parameters on web– Updated plots of raw sensor data (20 minute intervals)– Bi-Monthly plots of quality controlled data for the preceding period

• E-mail or telephone alerts to State/C&C Agencies– Sudden large changes in salinity, turbidity or nitrate at buoys and other sensors

• Maps of WQ parameters from REMUS surveys– Processed data set including gridded 2D and f(x,y,z,t) observations of temp, sal,

optical backscatter, fluorescence, velocity and acoustic backscatter  for events (10-12/year)

Other Existing Nearshore Observing Systems

• Kilo Nalu Nearshore Reef Observatory– Key component of HIOOS near Kewalo Basin– Cabled seafloor array with real-time data transmission to shore– Funded by various federal programs for basic physical

oceanographic and biogeochemical research

• CRIMP CO2 in Kaneohe Bay – Collaborative project with NOAA/PMEL, first buoy of federal

coastal CO2 monitoring network– Interdisciplinary research platform for sensor development– Locally funded by NOAA/Sea Grant College Program

Kilo Nalu Nearshore Reef Observatory

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Bathymetry in meters

• Waves

Directional wave spectraWave characteristics

• Currents vs depth (10m, 20m)• Water properties

Temperature vs depth (10m, 20m)Salinity, Dissolved Oxygen, Turbidity

and fluorescence (Chl-a) (10m)

Acoustic backscatter (10m, 20m)Moored profiler (20m: T, S, DO, Chl)

• Surface water quality buoy (at 10m site)

• Meteorological (JABSOM roof):Wind, air temp, rel. hum., rainfall, irradiance• Fall / Winter 2008:Temperature vs depth to 100mSpatial currents (2 ADCPs along 20m isobaths

www.soest.hawaii.edu/OE/KiloNalu

Ocean Observatory Technology/Applications: Kilo Nalu Observatory

A window into the Hawaiian coastal ocean environment…

Technological Development/R&DOcean technology test bed

Instrumentation

AUV/ROV applications

Passive acoustics

Ocean Observation/Prediction System:Real-time observations, validation

waves/currents/water chemistry

Autonomous Underwater Vehicle

(AUV) surveys

Adaptive sampling

Education, OutreachGraduate, undergraduate education

synergy with Bishop Museum

Funding: NSF CoOP, NSF OCE, ONR, UH Sea Grant

Kilo Nalu: Real-time Wave/Current Data

Waves (via ADCP at 10m, 20m, 20 min avg) Directional wave spectra, wave characteristicsCurrents vs depth (10m, 20m, 20 min avg)StratificationTemperature vs depth (10m, 20m), Salinity (10m)

• First buoy of the NOAA/PMEL coastal CO2 program

• First high temporal resolution time-series study for a tropical coastal embayment.

• >24 months of buoy data and synoptic water column data throughout K-bay

• Kaneohe Bay is a sink of CO2 during storms but remains a source to the atmosphere over annual scales

• Local research important in greenhouse gas budgets and ocean acidification (collaborations with F. Mackenzie, R. Feely, C. Sabine, W. Grossmann, etc.)

CRIMP CO2

http://www.pmel.noaa.gov/co2/coastal/kbay/157w_all.htm

Kaneohe Bay CRIMP CO2

• Multiparameter sondes (Conductivity/Salinity, T, pH, DO, Chl-a, Turb) at 10 minute frequency

• CO2, O2 sensors, CTD every

3 hours

• Climate from NWS, CI• Data telemetry by Iridium to

PMEL (daily plot updates on NOAA website)

• Synoptic profiles (Chl-a, Cond/Sal, DO, pH, Turbidity at multiple sites)

• Water samples for lab analyses

Hyperspectral imaging of coastal zone

Thermal infrared imaging (to evaluate extent of submarine groundwater and other freshwater discharges)

ADCP (current meters to be co-located with buoys and nearshore sensors and provide detailed coastal currents)

Flat panel interactive displays in public locations (e.g., yacht clubs, Waikiki Aquarium, hotels, paddling clubs, etc.)

Other (Currently Unfunded) Components of Potential Interest

Mapping coastal run-off

Hyperspectral Imagingof the Coastal Ocean

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Reef Health & Ecology

HIOOS Water Quality Network

• Strengths– near-real time

– complements existing agency monitoring

– covers most popular beaches on O‘ahu

– capable of detecting plumes (effluent, runoff, spills)

– data will be readily accessible

– Mostly Federally funded

• Weaknesses– cellular system vulnerable

(e.g., 2006 earthquake)

– may not differentiate between certain effluents, runoff, and spills

– cost currently precludes equipping buoys and NS arrays identically and fully

Time-series data useful to Local/State/Federal agencies

Development/testing site for new geochemical sensors

Series of complementary observatories provide broad range of data

Local but globally relevant data regarding direction and flux of greenhouse gases and ocean acidification

Training of technical workforce in ocean technology and outreach…

Value of Ocean Observing to Hawaii and Science

Mahalo for your attention

QUESTIONS?

Some Issues…

Stakeholders• Hawaii State Dept. of Health (CWB)

• C&C Honolulu, Dept. of Env. Services

• Waikiki Hotel Association

• Wastewater Treatment Plants

• 501-c-3 organizations interested in water quality

• Researchers interested in land-coastal interactions

• Environmental firms working in coastal waters

• K-12 schools (science programs)