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					GoMOOS Ocean Observation Technology:
        Present and Future
                 Neal R Pettigrew
             GoMOOS Chief Scientist
           Physical Oceanography Group
                University of Maine




                                  N
                  Outline
• The Gulf of Maine Ocean Observing System
  (GoMOOS) – Multiple purposes of Ocean
  Observing systems.
• Technology in GoMOOS. What does it do? How
  is it done? How will it expand and improve in the
  near future?
• Educational Challenges: What knowledge and
  skills are needed for those who will operate the
  OOS? What knowledge and skills are needed by
  those who will use GoMOOS in the classroom?
Multiple Purposes of the Observing System
• Scientific, Practical, and Educational Missions

   – Advance scientific understanding of how the Gulf of Maine
     operates as a physical and ecological system. Reveal the seasonal,
     interannual, and decadal variability of the oceanography of the
     Gulf of Maine and its major bays and estuaries, and the impact of
     this variability on fisheries and environmental quality.

   – Provide hourly real-time data to National Weather service
     (forecasting, winds and waves) USCG (search and rescue, oil spill
     response), shipping industry, fishing industry, and recreational
     boaters. Provide archived data, model output, data interpretations
     to environmental regulators and planners to facilitate the
     formulation of marine public policy.

   – Provide a window on the Gulf to educators and students in order to
     stimulate interest in the marine environment and to facilitate
     training for future scientists, engineers, technicians, managers and
     ocean educators.
              Technical Program
Real-time monitoring of meteorological and Oceanographic Conditions:

  Weather -- surface winds, air temperature, visibility (fog),
      incident light, barometric pressure*
 Oceanic conditions -- currents, waves, temperature, salinity
  Environmental quality – dissolved oxygen, inorganic
      nutrients*
 Ocean optics – Chlorophyll fluorescence , water-column
      light field, ocean color, multi-wavelength attenuation,
      water clarity
Modeling:
 circulation & waves
Web delivery of data and data products:
 Hourly data delivery:
       www.GoMOOS.org                   gyre@umeoce.maine.edu
   *coming soon
          GoMOOS Shelf Buoy
• “Unsinkable” combination
  of hard and soft flotation.
• Dual telemetry system:
  cellular/irridium phone
  and GOES satellite links.
• Stable enough to support
  technician topsides and
  build-up of sea ice on
  superstructure.
• Artificially intelligent -
  position, leak, and power
  alarms.
      Wind Sensor                   Lightning Arrester
Cell Phone Antenna                     Lantern
     GPS Antenna                       Temperature Sensor
   Visibility Sensor                   Radar Reflector

      Solar Panels

  Hinged Well Cover                       Water-proof
                                          Deck Connectors




      Built in wave accelerometer
Buoy Electronic in the well
           Control Box in Buoy Well

  Cover
  Gasket




                             Water-proof
                             Deck Connectors
Buoy Electronics
GoMOOS Shelf Buoy
Current measurements are made
using acoustic Doppler
technology.

Surface current meter 2.5
megahertz makes near-surface in
situ measurements.

Subsurface current measurements
made using a 300 kHz acoustic
Doppler profiler. Range ~150 m,
4 m vertical resolution of the
profile.
          Current Measurement and the
               Piezoelectric effect
• A voltage difference is generated between surfaces of solid dielectric
  materials (poor conductors, efficient supporters of electric fields)
  when a mechanical stress or compression is applied. Conversely,
  when a voltage is applied, a mechanical distortion occurs. Most
  commonly used piezoelectric materials are ceramics.

• If an oscillating voltage is applied to the surfaces of a ceramic
  cylinder, it oscillates at the same frequency as the voltage
  fluctuations applied….and generates compression waves in air or
  liquid that we refer to as sound. Conversely, if a ceramic cylinder is
  exposed to compression waves it will generate fluctuating voltages in
  response... We refer to these measured fluctuations as data. This
  reciprocal relationship between voltage and compression is the basis
  of acoustic transducer operation.

• Ceramics, quartz are two common piezoelectric material. Deep sea
  pressure sensors are made of quartz crystals. Acoustic transducers
  are made of ceramics, and hydrophones.
   Remote-sensing acoustic Doppler
   current measurement technology
• Sound is emitted by ceramic transducers and scattered by
  plankton embedded in the flow. Sound backscattered to
  the transducers is Doppler-shifted in frequency. The shift
  in frequency is proportional to the speed of the scatterers,
  and thus to the speed of the water.
Advantages of Acoustic Doppler technology
• No moving parts
• Immune to bio-fouling
• Can avoid self-wake contamination
• Profiler can act as the equivalent of 128 individual current
  meters.
GoMOOS Currents Meters
Near-Surface Current Measurements
• Use of Doppler Profilers for near-surface current
  measurement is problematic due to contamination in the
  near field from reverberations and side-lobe reflections
  from the sea surface.
• Aanderaa in situ Doppler current meter emits sound pulses
  that propagate horizontally from four transducers . Only
  “up Doppler” returns are used to eliminate the two
  channels potentially affected by instrument wake.
  Measurements are made between 0.5 m and 1.5 m from the
  instrument. The instrument is deployed at 2m depth so
  side lobes don’t reflect from the surface and cause
  contamination until the measurement is done and the
  instrument “stops listening.”
     GoMOOS
     Shelf Buoy
Inductive modem system
telemeters subsurface data
up the mooring cable.

Up to 100 subsurface
sensors addressable by the
inductive modem system.

Modular Design

Serviceable at Sea
             Buoy Architecture:
            The inductive modem
• Inductive modem
  technology based on
  transformer design.

• The mooring cable in used
  as the secondary winding.

• Voltage fluctuations (data)
  are induced in the mooring
  cable itself.
          How the system works
• Sensor mounted on Cable
  with primary winding
  attached.
• Induces Voltage
  fluctuations (data) in cable
  (secondary winding)
• Cable in turn induces
  voltage fluctuations in the
  inductive cable coupler,
  which is electrically
  connected to surface
  inductive modem in the
  buoy.
       Inductive cable coupler
• ICC attached on
  mooring cable above
  shallowest instrument.
• Electrical Cable
  attached to surface
  inductive modem
  inside the buoy
   Induction Modem Instruments

Temperature/Conductivyy
sensor with built in IM (right)


Diagram of Temperature/
Conductivity/ Dissolved Oxygen
Sesnor (far right)
External Inductive Modem
 Flexibility of the Inductive Modem
              Technology
• Up to 100 instruments can telemeter data up the
  mooring cable without direct electrical connection
  to the buoy! (avoids electrical trunk line)
• Instruments can be mounted at any depth, and
  their positions changed without requiring redesign
  or remanufacture of the cable.
• Relative positions of sensors may be switched
  with only a software change.
• Instruments can be removed or replaced by divers
  without requiring recovery of the buoy itself
  (MAJOR OPERATION).
                          Buoy Deployment
•   Buoy deployment and
    recovery are major
    operations.
•   GoMOOS has built 21
    buoys for 10 monitoring
    locations. Each buoy pair
    rotated on 6 month rotation
    schedule. The extra buoy is
    for emergency response.
•   A smaller nearshore version
    of the GoMOOS buoy is
    being designed. The
    nearshore buoy will be
    deployable from Lobster
    Boats. Mini buoy designed
    for estuarine envronments.
  Measurement of Surface Currents
        using radio waves
• Surface currents, averaged over several square kilometers,
  can be measured out to a range of 100-200 kilometers from
  shore using a radio wave system called Coastal Ocean
  Dynamics Applications Radar (CODAR). It is not a
  microwave radar… it has a wavelength of 10s of meters
  and is in a frequency band between AM and FM radio.
• It is a remote sensing system, immune to cloud cover and
  fog. However its use depends upon presence of short
  surface water waves, and the long-range CODAR is
  susceptible to ionospheric interference.
• Requires multiple shore stations and large antennas.
Uses of CODAR Current Data in the GOM
                         Schematic of the Summer Circulation of the Gulf of Maine

• The monitoring the
  surface circulation
  independent of fog
  and cloud cover.
• Pollutant and larval
  transport.
• Search and rescue.

                                                            Pettigrew, 1996
    CODAR Operating Principals
• Radio “ground wave” propagates well along the air-sea interface, but
  dies out rapidly over land.
• Bragg scattering– Radio waves propagating over the wavy sea
  surface will be scattered by sea surface waves. The scattering by water
  waves of precisely half the radio wavelength is directly back toward
  the radio source rather than in all directions. This phenomenon causes
  the scattering from one surface wave to dominate the returns from all
  other surface waves.
• The back-scattered radio signal will be Doppler shifted because 1)
  waves are moving, and 2) surface currents.
• Wave speed can be compensated since it is a function of its known
  wavelength in deep water.
• The remaining Doppler shift is caused by, and proportional to, surface
  currents (and noise)!
        Long Range CODAR
• New Long range systems operate in the 4 -5
  megahertz shortwave band. Between AM and FM
  bands.
• Bragg scattering occurs from waves of
  approximately 30 m wavelength….~4.5 sec
  periods. These waves are nearly always present
  and are generated by light transient winds.
• Range of the systems are 100 -200 km depending
  on background radio noise and ionospheric
  interference.
CODAR Installation (Green’s Island)
      Theoretical coverage of long-range
        CODAR in the Gulf of Maine
• Areas of overlapping
  coverage provide two-
  dimensional surface
  current measurements.
• CODAR-derived
  surface currents have
  been shown to correlate
  well with GoMOOS
  Doppler currents at 2m.
• Long-range CODAR
  offers an opportunity
  for early connections of
  regional observing
  systems
  CODAR Current Vector Fields
• First panel shows vectors
  from the Greens Island
  and Cape Saint Mary
  installations.

• The second panel shows
  results from Nantucket,
  Block Island, Long Island,
  and New Jersey
  installations.
Greens Island CODAR-Buoy M
 Surface Current Comparison
      Future GoMOOS Developments
•   Moored real-time nutrient sensors.
•   Smaller, cheaper, more easily deployed near-shore buoys to monitor estuary-
    shelf and estuary-estuary coupling.
•   Additional buoys farther offshore to monitor the inflows and outflows to the
    Gulf of Maine and conditions in the basins.
•   Short range high speed wireless connections between ships and buoys so that
    buoys can be checked after deployment and sensors reprogrammed etc.
    without the necessity of pulling the buoy on deck and physically plugging into
    it.
•   Other forms of satellite telemetry… short message service, direct internet
    connection. Cheaper, but one way communication…. Just receive data, can’t
    send commands.
•   Replace in situ optical, hydrographic, and DO sensors with vertically profiling
    packages.
•   Coupled physical and ecological models “on line” to fill in the gaps between
    observations and to predict changes.
•   “Development buoy” for testing and integrating new sensors, data systems,
    telemetry etc., allowing the evolution of the GoMOOS system without
    jeopardizing the sustained real-time monitoring mission of the observing
    system.
•   Buoy-mounted CODAR systems for expanded coverage, reduced error, and
    long-range ship tracking.
  GoMOOS/NOAA Monitoring Array
• Large unlabeled red
  dots indicate the
  locations of potential                                       .
  GoMOOS real-time
  data buoys for the                              .. . . . .   .
  interior of the Gulf.                                        44027


  Georges Bank and the              . .. .
  Scotian shelf are areas
  that would tie
  GoMOOS to a larger            .     .                                    .
  regional system.
                            .             .                . ..           N
• Small unlabeled red
  dots indicate potential       . .                       . .
  locations of nearshore
  and harbor buoys.
                                              .
                                              44018


                                                                       44011
      Future GoMOOS Developments
•   Moored real-time nutrient sensors.
•   Smaller, cheaper, more easily deployed near-shore buoys to monitor estuary-
    shelf and estuary-estuary coupling.
•   Additional buoys farther offshore to monitor the inflows and outflows to the
    Gulf of Maine.
•   Short range high speed wireless connections between ship and buoys so that
    buoys can be checked after deployment and sensors reprogrammed etc.
    without the necessity of pulling the buoy on deck and physically plugging into
    it.
•   Other forms of telemetry… short message service, direct internet connection.
    Cheaper, but one way communication…. Just receive data.
•   Replace in situ optical, hydrographic, and DO sensors with vertically profiling
    packages.
•   Coupled physical and ecological models “on line” to fill in the gaps between
    observations and to predict changes.
•   “Development buoy” for testing and integrating new sensors, data systems,
    telemetry etc., allowing the evolution of the GoMOOS system without
    jeopardizing the sustained real-time monitoring mission of the observing
    system.
•   Buoy-mounted CODAR systems for expanded coverage, reduced error, and
    long-range ship tracking.
      Future GoMOOS Developments
•   Moored real-time nutrient sensors.
•   Smaller, cheaper, more easily deployed near-shore buoys to monitor estuary-
    shelf and estuary-estuary coupling.
•   Additional buoys farther offshore to monitor the inflows and outflows to the
    Gulf of Maine.
•   Short range high speed wireless connections between ship and buoys so that
    buoys can be checked after deployment and sensors reprogrammed etc.
    without the necessity of pulling the buoy on deck and physically plugging into
    it.
•   Other forms of telemetry… short message service, direct internet connection.
    Cheaper, but one way communication…. Just receive data.
•   Replace in situ optical, hydrographic, and DO sensors with vertically profiling
    packages.
•   Coupled physical and ecological models “on line” to fill in the gaps between
    observations and to predict changes.
•   “Development buoy” for testing and integrating new sensors, data systems,
    telemetry etc., allowing the evolution of the GoMOOS system without
    jeopardizing the sustained real-time monitoring mission of the observing
    system.
•   Buoy-mounted CODAR systems for expanded coverage, reduced error, and
    long-range ship tracking.
   Gulf of Maine
Ecosystem Modeling
         Fei CHAI
         Huijie Xue
 School of Marine Sciences
    University of Maine
Carbon, Silicate, Nitrogen Ecosystem Model
                                                                                        Air-Sea
CoSiNE, Chai et al. 2002; Dugdale et al. 2002                                          Exchange
            Micro-                            Small                  Biological
         Zooplankton          Grazing     Phytoplankton               Uptake        Total CO2
             [Z1]                              [P1]                                  [TCO2]
                                                                    NO3
                                                       NH4         Uptake
         Predation                                    Uptake
                                                                            Nitrate
                              Excretion                                      [NO3]
             Meso-                                             N-Uptake
Fecal                                        Ammonium
Pellet    zooplankton
                                               [NH4]                          Advaction
              [Z2]                                                            & Mixing

           Lost      Fecal         Grazing
                     Pellet                                            Diatoms
                                                                         [P2]
   Detritus-N           Detritus-Si
     [DN]                 [DSi]                          Si-Uptake
                                                                          Sinking

Sinking                                 Dissolution     Silicate                      Physical
                              Sinking
                                                       [Si(OH)4]                       Model
Chai et al., 2003; Jiang and Chai, 2004
Welcome to the Gulf of Maine
Ecosystem Modeling Website
  (internal use only for now)




An ecosystem model embedded in
the GoMOOS circulation forecast model
Physical-biological model results need to be analyzed
Ecosystem model performance needs to be improved
Daily Nutrient and plankton forecast for the Gulf of Maine
              On the horizon
• New instrument platforms: Gliders, AUVs, SAVs,
  intelligent profiling floats.
• DNA probes to detect red tides and other harmful
  algal blooms, coliform bacteria. Dr. Laurie
  Connell, SMS University of Maine.
• Seamless observational and data base system
  integration of GoMOOS with other regional
  observing systems into a North American
  Observing system.
• Slocum coastal glider
• 2-3 week mission
  duration in shallow
  water.
• Sensors: CTD,
  Oxygen optode,
  fluorometer.
                   Solar Auv
• ~2 knot cruising speed
• “extended missions”
  on the order several
  days.
• Aprox 4-5 times the
  spatial coverage per
  unit time as compared
  with the glider.

				
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