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The mooring site in the Central
Irminger Sea (CIS) was first deployed in August
2002. The site is located in a region with
exceptional hash surface conditions (wind, waves)
and vivid fishery activity. To allow for near real
time data telemetry the surface telemetry buoy
design was a challenging task. To minimize the
drag on the mooring wire a small (17” or about
50 cm diameter) and lightweight (about 50 kg)
glass sphere was used to hold all electronics and
batteries for data transmission via ARGOS. The set
up of the site was initiated in the ANIMATE
project,
an EU effort under the FP-5.
The initial mooring design
was a composite of two moorings: one for physical
data acquisitions (temperature, salinity) with the
telemetry buoy, the other mooring with a
biogeochemical sensor (pCO2, Nitrate,
Chl-a) frame at 50m depth and up and downward
looking ADCP current recorder at 150m depth. With
increasing experience and confidence in components
and design a single mooring which holds all
components on one wire was first successfully
deployed in May 2004 (click here for a mooring
diagram in PDF). A redeployment was done in Sept.
2004 and the last redeployment was done in
September 2005.
Since
September 2005 the mooring carries a full suite
of sensors - temperature and salinity to 1500 m
depth, ADCP current profilers, and pCO2,
nitrate, chlorophyll sensors. Not only the
physical but most of the biogeochemical sensors
are incorporated into the telemetry loop. The
real time data enters the MERSEA data stream.
The quality controlled delayed-mode is also
available.
Status:
Mooring is in water - next service 3. July to
17. July 2007 from the German Research Vessel
Maria S. Merian (cruise MSM05/4) from Nuuk/Greenland
to Reykjavik/Iceland.
Data:
Realtime data from temperature, pressure,
conductivity (salinity), pCO2, and chlorophyll-a
is available.
Here
are a few selected graphics from the CIS time
series:
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32" floatation (foreground) with frame that
holds the biogeochemcial sensors (SAMI pCO2,
NAS nitrate, Wetlab Cholorphyll-a). A 45"
floatation (background) which holds two
ADCP's (upward and downward looking) allow
to measure current speed and direction in
the upper 600m of the water column. Both
floatation are prepared and ready for
deployment. |
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The electronics for the telemetry buoy are
hosted by a 12" floatation. Here shown
without the yellow plastic protection.
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A conductive swivel is mounted at the base
of the 45" double ADCP floatation that will
be at 150m depth after deployment. The
swivel allows to bridge the floatation for
transmission of data from deeper sensors. |
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The last part of the
mooring, a 1500kg rail wheels anchor is
launched. The anchor sinks to the ocean
bottom and holds the mooring at place.
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