Marlin-Yug announces Iridium prototype of temperature-profiling drifters SVP-TC80 and SVP-BTC80 with nominal depth of profiling 80m

The experience of SVP-BTC drifter and its SVP-TC modification without air pressure sensor evaluation has shown that design of temperature-profiling buoy with temperature chain attached to bottom ring of holey sock drogue has some advantages in contrast with buoy having the chain connected directly with surface float. First of all, this buoy has better quality of temperature measurements because of vertical stabilization of the chain. This is possible due to large hydrodynamic vertical inertia of drogue in water, when bottom end of the drogue has small vertical oscillation in spite of wave influence on buoy as a whole. As a result, the chain does not practically have the vertical jerks, and correspondently – smaller space deformation of own profile. In addition the chain has a decreased breaking load, that allows using of chain with small diameter and provides better Lagrangian parameters for drifter. SVP-BTC drifter deployed in 2008 by Meteo-France in the Atlantic Ocean demonstrated that last prototype of buoy kept a quality of temperature measurements longer than six months. 2009 prototype of temperature profiling drifter has a few additional novelties. This buoy can transmit data via Argos or Iridium systems. It has Real Time Clock, that allows synchronous measurements of temperature profiles within active layer by set of drifters. At last, the buoy has factory installed software to transmit data from chain with pairs: real depth of each sensor and corresponding temperature independently of a chain deflection.  Fragment of temperature data from SVP-BTC ID49678 deployed by Meteo-France in Atlantic Ocean (June-November 2008)