Site: Greenland Sea Position: 75 º n 5º w categories

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  One or two moorings about 75° N, between 2° 30' W and 4° 20' W
  
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  Variables measured: Alternate-daily pofiles, 100-3700 m, CTD
  
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  Start date of the timeseries: 1999
  
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  service interval: yearly
  

Exchanges between the North Atlantic and the Arctic Ocean result in the most dramatic water mass conversions in the World Ocean: warm and saline Atlantic waters flow through the Greenland Sea into the Arctic Ocean, and shallow fresh waters and ice exit the Arctic towards south. In the link between both oceans, the Greenland Sea, these waters are modified by cooling, freezing and melting to become deep waters. Understanding of the modification processes is a major prerequisite for the quantification of the rate of overturning within the large circulation cells of the Arctic and the Atlantic Oceans.

The mooring monitors changes of physical parameters in the water column between ca. 100 m and the ocean bottom (3700 m) in the Greenland Sea. This is used to identify convective events and to monitor ventilation history and trends in the water column.
Groups / P.I.s /labs /countries involved / responsible: AWI, Gereon Budéus
Status:

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  operational
  
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  funded, national funding
  

Autonomous self contained moored Deep Sea Profiler 'EP/CC-JoJo' (Externally Powered/ Compressibility Compensated-Jojo). The EP/CC-JoJo is a moored profiler designed for fast and numerous deep sea profiles.

Basic demands were

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  deep profiles (typically 4000 m)
  

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  many profiles (typically ca. 300, i.e. daily or alternate-daily profiles for 1 year)
  

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  self contained vehicle (internal data storage to avoid problems with ice in arctic regions)
  

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  measure C,T and p with precision high enough to indicate convective events in polar regions
  

Can be used to identify convective events and to monitor ventilation history and trends in the water column

Figure 1 Control unit containing the weights to drive the downcast of the vehicle.	Figure 2 The vehicle, consisting of instrument and bouyancy module, in the lab. Beside a complete vehicle, internal parts are displayed.