INTERNATIONAL ARCTIC RESEARCH CENTER — UNIVERSITY OF ALASKA FAIRBANKS

NABOS Technology

Moorings

Moorings are an important part of NABOS research. They allow the scientists to position instruments in the ocean for years at a time.
Moorings are an important part of NABOS research. They allow the scientists to position instruments in the ocean for years at a time.

Technical information

Distributed moorings

Moorings are an important element of the program. Some have been maintained since 2002. Our moorings are providing key information about strong Eurasian Basin (EB) warming and have helped estimations of transit times required for signals to travel from Fram Strait to the basin interior.

Previous observations have demonstrated rather uniform vertical structure of the boundary current in the Atlantic Water (AW) and halocline; thus, the proposed design must be sufficient to capture AW transports. These moorings complement snapshot ship-based observations at distributed cross-sections providing climatologic context to the snapshot measurements.

  • The mooring locations in the Laptev Sea (M1 and M3, above) and East Siberian Sea (M9) are reliable climatological sites. Data from these locations have been used for monitoring climatic changes.
  • The mooring site north of Severnaya Zemlya (M5) is close to the frontal zone between the AW Fram Strait and Barents Sea branches and to a polynya region; therefore, it is more susceptible to local processes like down-slope cascading of dense shelf waters. Data from this mooring bridges snapshot CTD observations taken at the 90°E cross-slope section carried out every other year. These moorings use “conventional,” reliable equipment: fixed-depth CTDs, SBE-37s (“microcats”) to measure temperature and salinity, and ADCPs to measure currents.

Two of the moorings (M1 and M9) are equipped with upward-looking bottom-tracking ADCPs to measure current profile and to monitor ice drift; they will also have Upward Looking Sonar (ULS) for ice draft measurements. CTD chains affixed to two moorings (M3 and M5) will be located above major flotation to measure surface boundary layer T and S.

Ocean Bottom Pressure (OBP) variations are tracked at M1 and M9 using Sea-Bird BPR-53 meters. We will compare these observations with Dynamic Ocean Topography (DOT) derived from the CryoSat-2 altimeter to test satellite-derived estimates of Arctic Ocean circulation and freshwater distribution.

Cross-slope mooring section
Lagrangian buoys (partners' programs)