Irminger Sea
Mozambique Channel
Eastern Indonesia
Canary Basin
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Long-Term Ocean Climate Observations (LOCO)
CANARY BASIN
The large-scale meridional overturning circulation in the ocean cannot exist without small-scale mixing that redistributes heat. In the ocean interior, the key mechanism for this mixing seems to be the breaking of small-scale internal waves. As this is induced by large-scale internal wave shear, dominated at tidal and inertial frequencie, the study of large-scale changes of these internal waves is a prerequisite to study variability in ocean mixing and, thus, in the large scale circulation.   Internal tides have well-known frequencies, but may vary as supporting background stratification varies (in the vicinity of topographic features). More unknown, and therefore specific subject of our studies, is the climatology of deep (near-)inertial motions. These are generated near the ocean surface by passages of atmospheric disturbances. Unknown to-date are the precise transport of inertial energy from their source to greater depths and different latitudes and the precise mechanism of energy redistribution within the internal wave band.
Within the LOCO project two sets of four moorings each are used to study in more detail the climatological mean of spatial and temporal variability of internal-wave intensity.   The first set of moorings was deployed in the Canary Basin around 30º N during the LOCO-IW03 cruise (64PE208) in March 2003. The Canary Basin is a deep-ocean basin. The moorings will be deployed for a period of 5 years to study near-inertial internal motions generated by atmospheric disturbances and by diurnal tides. The moorings contain current meters and temperature sensors and extend up to 3.7 km above the bottom ( = 1.5 km below the sea surface). In addition, short-term hydrographic and mixing information was collected during the cruise, using CTD, XCP and LADCP in the vicinity of the moorings.	Acoustic Releases used to release moorings
The second set of moorings is currently located above sloping topography in the Irminger Sea near 60º N. After 1½ year, this set will be recovered and re-deployed in the Mozambique Channel. This second set of moorings is used to study specific processes like internal wave focusing and effects of convection.
List of Research Cruises:   ·         North/South Atlantic Ocean [ 64PE280 ] - RV Pelagia (June/July 2009)   ·         North/South Atlantic Ocean [ 64PE279 ] - RV Pelagia (November/December 2007)   ·         North Atlantic Ocean [ 64PE248 ] (Note: combined BSIK/LOCO-IW/Towed ADCP cruise) - RV Pelagia (May/June 2006)   ·         North Atlantic Ocean [ 64PE231 ] - RV Pelagia (October/November 2004)   ·         North Atlantic Ocean [ 64PE208 ] - RV Pelagia (February/March 2003)