Introduction - Kannad PROV-CARBON Manuel Utilisateur

USER MANUAL / MANUEL UTILISATEUR

1. INTRODUCTION

PROV-CARBON is a subsurface profiling float developed jointly by IFREMER and KANNAD Group.
The PROV-CARBON float has been developed on the basis of CTS-3 PROVOR float previously designed
for Argo program with the addition of oxygen and transmittance sensors.
The addition of such sensors involves the use of the IRIDIUM satellites communication system.
After launch, PROV-CARBON's mission consists of a repeating cycle of descent, submerged drift, ascent
and data transmission. During these cycles, PROV-CARBON dynamically controls its buoyancy with a
hydraulic system. This hydraulic system adjusts the density of the float causing it to descend, ascend or
hover at a constant depth in the ocean.
The user selects the depth at which the system drifts between descent and ascent profiles. PROV-CARBON
continually samples the pressure at this drift depth and maintains that depth within approximately 30 m.
After the submerged drift portion of a cycle, the float proceeds to the depth at which the ascending profile
is to begin. The ascent profile starting depth (typically the Argo-selected depth of 2,000 m) is not necessarily
the same as the drift depth.
During its mission, PROV-CARBON collects measurements of three parameters «salinity, temperature,
depth (CTD)» as well as those of dissolved oxygen (DO) and transmittance parameters then saves them in
its memory. The CTD and DO measurements can be made during the float descent (descent profile), during
the submerged drift period (Lagrangian operation) and during the ascent (ascent profile), the transmittance
measurements can be made only during the submerged drift and the ascent.
Unlike ARGO float, the ascent is programmed to reach the surface at a pre-defined time.
After each ascent, PROV-CARBON transmits its saved data to satellites of the IRIDIUMs system. The
volume of data is reduced using a compression algorithm in order to reduce the time needed for
transmission. While on surface thanks to a GPS receiver, an accurate position of the float can be obtained
and the clock of the float be updated.
This manual describes the PROV-CARBON float, how to use it and safety precautions to be observed
during handling.
Please read this manual carefully to ensure that PROV-CARBON functions as intended.
The descending and ascending profiles are almost identical, indicating that the float operation was in the
same water mass for the entire test.
PROV-CARBON
PAGE : 1 / 70
DATE : 20/12/2007
INDEX : A
REF. : DOC07220