Development and Testing of a Mooring System for monitoring Long-term Oceanic Multi-scale Dynamic Process

An integrated mooring system was developed and preliminarily tested in the demand of monitoring and investigating oceanic multi-scale physical processes such as that energy cascadings from large scale motions to mesoscale and then small scale motions, and finally the energy dissipated as microscale turbulence. In the mooring system, a turbulent meter was designed and integrated to measure turbulence kinetic energy(TKE) dissipation rate at fixed depth. The integrated mooring system, constituted of a turbulence meter, a current meter and CTD, was preliminary tested in Jiaozhou Bay and on March 2010. The turbulent meter directly measure current shear with a shear probe and instrument motions with linear accelerations. Motions due to vortex-induced vibrations caused by interaction of the mean flow with the cable contaminated the shear signal and cannot be ignored. The uncontaminated signal was retrieved by removing the part of the measured signal that is coherent with the signal induced by cable motions. Comparison of TKE dissipation rate at the same depth obtained by the turbulent meter and a microstructure profiler MSS60 showed a good agreement with each other within a factor of 2. In the future, the mooring system was designed to integrate long range ADCP for current profiles, turbulent meter for microstructure and chains of CTD and temperature loggers for T, S profiles measurement. This will play a key role in investigating the kinetic characteristics and mechanisms of multi-scale motions in the ocean.