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					Sea Level Sensors and Equipment

 Bureau of Meteorology
Fibreglass Huts

   Spring Bay,
    Tasmania.

 Australian huts have
 fewer vents, thinner
   walls, less timber
reinforcing, shallower
roof pitch than Pacific
          huts.
     NTC Calibration Procedure
• High, low and mean
  marked on cal rig.
• Delta Test adjusts for
  linearity. 1mm of tube
  length = 1mm of readings.
• Steel collar adjusted to
  correct linearity, lab only.
• Offset Test determines
  sensor zero KA3 value
• Distances from sensor to a
  simulated water level are
  measured physically and
  electronicly. The
  difference is = KA3.
     Aquatrak water level sensor
• Model 3000 NG-XCR
• Connects to a B63 RS232
   module via a Bartex 4110
   controller.
eg serial no. 1076-3417
1076 for electronics
3417 for acoustic sensor.

Calibration coefficient no.1,
   eg, 1114.35 mm for
   Sutron 9000
or KA3, eg, -104.27 mm. for
   Telmet T320.
                 Aquatrak Connections
•   +12 volts – red - D
•   Ground – black - A
•   Drive – white - E
•   Cal – green- B
•   Water – blue – C


Drive is a 100microSec pulse.
Cal and Water - several pulses.
Speaker then microphone.
                  Aquatrak Faults
• Zero output, 0.000 from sensor – flat line.
   One or more broken wires.
   Calibration reflection signal not received
   Calibration hole blocked.


• Noisy tidal plots –
   – Water droplets or other moveable debris around cal hole or on
     surface of water.


• Flat tidal plot at certain heights
   – Debris stuck in tube but covered as water rises.
Aquatrak Circuit Diagram,
     C2 gives the most trouble.
             Calibration Tube
• Aquatrak and Cal
  Tube are calibrated
  and stay together
  when deployed.
• Tube has a small hole
  on its side 1.1 metres
  from the top.
           Aquatrak Removal
• 3/32 Allen key grub
  screw – not too tight.

• Calibration Tube,
  brittle upvc, can snap
  when jarred.
                  Levelling
• A & B Levels, KA2,
  and sensor coefficient,
  KA3,to go into the
  Telmet as override
  values.
• Recorded into SitesDB
  and Data Group Table.
Aquatrak Levelling

 • Measuring the Survey
   bolt and calibration
   tube levelling points,
 • “A & B”
 • Accuracy essential.
 • Levelling or Geodesy
   information back to
   NTC & SitesDB.
 • Data Group Table
           NTC levelling information
• Being accurate and
  mistake free is critical for
  measuring sea level
  change.
• KA1, sea level station
  bench mark SSBM.
• KA2, Offset, =B-A,
  distance from Survey bolt
  to sensor, enter into
  Telmet.
• KA3, sensor coefficient,
  enter into Telmet.
• AHD, Australian Height
  Datum
• CD, Chart Datum
• K values entered as
  override entries.
       On Site Aquatrak Replacement
•   Disconnect cable.
•   Remove Aquatrak, 3/32 allan key
•   Measure A & B
•   Disconnect Temp Probe
    connectors, T1, T2, Tw.
•   T1 & T2 – B36V inst #1.
•   Tw – B36V inst. #0.
•   Remove Cal Tube clamp, do not
    drop.
•   Slide up Cal Tube to remove.
•   Broome tube is 16m long.
                Sounding Tube
•   Careful with tube joiners
    – glue can crack.
•   Tube is upvc
    unplasticised polyvinyl
    chloride.
•   Use a file to draw a
    string through tube.
•   Pull a cloth from top to
    bottom.
•   Don’t lose sections in
    water.
           Bartex 4110 controller
• Interfaces directly with
  the Aquatrak
• Connects with the B63
  module, instance #1.
• Refer to ETB
  ETB_320_B63_AQU_02
  for setup.
                   Druck PDCR1830
• Connects to B36V module.
• 4 Wire water pressure sensor. Red White
  Yellow Blue.
• Bridge device
• Venting tube supplies atmospheric pressure
  behind the pressure plate.
• Output proportional to supply voltage, 5V
• 1 metre of water gives 5 mvolts output
• 10 metres = 50mV
• 10 metres of water depth = 1 atmosphere of
  pressure.
                Druck Bubbler System
• Nitrogen gas released through a tube underwater.
• Type 32 N2, Size G.
• Tide height varies the amount of back pressure in
  tubing.
               Vegapuls 62
• Communicates to Telmet via 4-20mA resistor and
  B36I module.
• Hart modem connects to either NextG router or
  BGAN satellite.
• Pactware configuration software
            Comparison sites
Two Aquatrak sensors
  installed at –
• Port Kembla, NSW.
• Thevenard, SA
• Groote Eylandt, NT.
• Rosslyn Bay, Qld.

One for Sutron 9000, the
 other for Telmet T320.
             Environment Tube
• Supports and protects the Aquatrak and Cal tube.
• Reduces higher frequency wave action.
Copper Plates, orifice cone.
    Reduces marine growth and surge.
     Posts can be bolted or peened.
Orifice top view,
3 to 1 reduction.
Marine Growth
        Environment tube &
          Sounding tube
• Attached to side of
  wharf.
• Copper parts below
  lowest tide level.
          Temperature Probe Check
• All temperature probes and
  thermometer are taped together
  and allowed to stabilise.
• T1, T2, old and new Tw
• Old Tb from Sutron 8200 not
  used with Telmet T320.
• YSI 46032 thermistor 30k
  ohms at 25 Deg C
         Sounding Tube detail
• Temp probes are cable
  tied to sounding tube
• Lower section of tube
  is copper, less marine
  growth.
• Tw at the end.
• T1 & T2 always above
  the water.
                   String Test
• Drop a string from the
  Aquatrak levelling point
  to the water.
• Measure length of string.
• Measurement should equal
  raw sensor value + KA3
• Ensures that reading is
  from the water, not any of
  the tube joins.
        Underwater Inspection
• Druck sensor secured
  in clamp
• Orifice open and clear
• Copper plates clean
Site Visit Procedure

• 26 Pages detailing the
  steps to maintain a
  SEAFRAME (Aquatrak)
  station
        Sea Level Networks
• Australian Baseline, ABSLMA
• South Pacific Sea Level & Climate Monitoring
  Project, SPSLCMP
• Australian Tsunami Warning System ATWS
• Some AWS sites are shared between networks.
     Monitoring and Metadata
• Netmon. Network monitoring
• MetTerminal. Individual station monitoring
• SitesDB. Station details and history.
                      Tsunami Monitoring
•   http://ntcweb.bom.gov.au/TEXT/FTP/TSUNAMI/reports.shtml
PNG Tsunami Observation 1 day
Pacific Residuals,

Japanese Tsunami

11th March 2011
 Sea Level Rise
• Variation in sea level
• ENSO
• El Nino , La Nina, 3-7
  years
• SOI, Southern
  Oscillation Index
• Currently in La Nina,
  ie warmer water,
  lower pressure and
  higher sea levels for
  western Pacific.
         Australian Sea Level Trend
                                                               Change in trend from June
   Location      Installation Date   Sea Level Trend (mm/yr)
                                                                    2009 (mm/yr)

Cocos Islands       Sep 1992                   8.7                        0.3

Groote Eylandt      Sep 1993                   7.1                       -0.4

   Darwin           May 1990                   7.2                       -0.5

   Broome           Nov 1991                   7.8                       -1.1

   Hillarys         Nov 1991                   7.6                       -1.2

 Esperance          Mar 1992                   5.3                       -0.8

 Thevenard          Mar 1992                   4.2                       -0.3

 Port Stanvac       Jun 1992                   5.0                       -0.5

   Portland          Jul 1991                  3.0                       -0.1

    Lorne           Jan 1993                   1.3                       -0.4

 Stony Point        Jan 1993                   1.3                       -0.4

   Burnie           Sep 1992                   2.9                        0.2

 Spring Bay         May 1991                   3.4                        0.1

 Port Kembla         Jul 1991                  3.0                       -0.1

 Rosslyn Bay        Jun 1992                   2.3                        0.4

Cape Ferguson       Sep 1991                   3.4                        0.4
Sea Level change, mm/year
Tidal Predictions

• Observations required
  to produce Tidal
  Predictions
  Pacific
Observations
Geodetic Datums, Land Movement
                20                                                                                            20
                         TG relative to TGBM                                                                           TG relative to TGBM
                         TG relative to CGPSBM                                                                         TG relative to CGPSBM
                15                                                                                            15


                10                                                                                            10


                5                                                                                              5
  Millimetres




                                                                                                Millimetres
                0                                                                                              0


                -5                                                                                            -5


            -10                                                                                           -10


            -15                                                                                           -15
                     Fiji 0.6 mm/yr                                                                                Cook Islands -0.7 mm/yr
            -20                                                                                           -20
              1992      1994     1996          1998   2000   2002   2004   2006   2008   2010               1992      1994      1996         1998    2000      2002   2004   2006   2008   2010
                                                         Year                                                                                               Year




                20                                                                                            20
                         TG relative to TGBM                                                                           TG relative to TGBM
                         TG relative to CGPSBM                                                                         TG relative to CGPSBM
                15                                                                                            15


                10                                                                                            10


                5                                                                                             5
                                                                                                Millimetres
  Millimetres




                0                                                                                             0


                -5                                                                                            -5


            -10                                                                                           -10


            -15                                                                                           -15
                     Kiribati +0.0 mm/yr                                                                           Tonga -0.4 mm/yr
            -20                                                                                           -20
              1992      1994     1996          1998   2000   2002   2004   2006   2008   2010               1992      1994      1996         1998    2000      2002   2004   2006   2008   2010
                                                         Year                                                                                           Year




                20                                                                                            20
                         TG relative to TGBM                                                                            TG relative to TGBM
                         TG relative to CGPSBM                                                                          TG relative to CGPSBM
                15                                                                                            15


                10                                                                                            10


                5                                                                                              5
  Millimetres




                                                                                                Millimetres




                0                                                                                              0


                -5                                                                                            -5


            -10                                                                                           -10


            -15                                                                                           -15
                     Samoa -0.9 mm/yr                                                                              FSM -0.4 mm/yr
            -20                                                                                           -20
              1992      1994     1996          1998   2000   2002   2004   2006   2008   2010               1992      1994      1996          1998   2000      2002   2004   2006   2008   2010
                                                         Year                                                                                               Year
              20
                       TG relative to TGBM
                       TG relative to CGPSBM
              15


              10


              5
Millimetres




              0


              -5


          -10


          -15
                   Fiji 0.6 mm/yr
          -20
            1992      1994     1996          1998   2000   2002   2004   2006   2008   2010
                                                       Year
Groote Eylandt
          OH&S and Site Access
• JSA, Job Safety Analysis.
• Risk Assessment, Hazard
  Identification.
• MSIC cards.
• Harbour site safety
  induction.
• Access cards.
• Buoyancy vests & Safety
  Harnesses.
• Drug and Alcohol testing.

				
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posted:8/12/2012
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