EurOCEAN 2000 - Vlaams Instituut voor de Zee

5. EXAMPLE OF RISING MEASUREMENTS
Rising measurements with the MSS profiler and the accessories as described in the previous
chapter have been carried out the first time during the MITEC-Cyano 99 cruise in the Baltic
Sea in July 1999. The guide pulley has been deployed approx. 150 m away from the ship (rv
Aranda) in a water depth of 50 m. The ship was kept at position by dynamical positioning. A
Figure 3a: Measurements of temperature with the rising MSS profiler of the Space
Applications Institute , JRC, during the MITEC-Cyano 99 cruise in the Baltic Sea in July 1999.
series of 102 rising profiles from 35 m depth up to the surface were taken in 5 min intervals.
The rising speed of the MSS profiler war adjusted to approx. 0.65 m/s. Principally, the
complete system worked properly. Figure 3 shows the near surface temperature and dissipation
rate time series as measured during this campaign.
Summarising the experiences with the rising microstructure measuring system for shallow
water, it can be stated, that the combination of guide pulley, buoyancy body, and swimming
cable is a proper arrangement for rising measurements in shallow water. This is especially
valid for measurements from a stable platform or from the shore of a lake. At water velocities
up to 0.30 m/s, rising measurements in 30 m depth intervals are possible.
If the measurements are done from a ship, a critical factor is to avoid movements of the ship.
The positioning of the ship should be stable within distances of less than 20 m.
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