As part of projects funded by agencies in France (ANR, CNES, EQUIPEX) and Europe (ERC), the Laboratoire d’Océanographie de Villefranche (LOV) has developed high-tech versions of bio-optical and biogeochemical profiling floats (Bio-Argo floats). These technological developments have been achieved through solid (and lengthy) interactions with companies involved in sensor development (e.g. Wetlabs, Satlantic) and platform conception (NKE). Preliminary studies based on the first versions of these floats were conducted in various regions of the World Ocean (see http://www.newoao.obs-vlfr.fr/), showing that the scientific benefits of using Bio-Argo floats were potentially very high. As part of the ERC remOcean and the Equipex NAOS projects, the technological developments initiated under the ERC funding were further continued, and the new generation of Bio-Argo floats is now fully operational. These floats have reached a degree of maturity that allow cutting-edge observations to be undertaken in a variety of environments, including the harshest and most remote ones (including the eye of a tropical cyclone). The SOCLIM project will thus benefit from the experience and feedbacks gained over several years of successful developments. In particular we propose to deploy two types of floats described below, i.e. PROVBIO-2 and PROVAL.
The PROVBIO-2 float is dedicated to biogeochemical studies. This float is a Lagrangian Argo-type (PROVOR CTD) float on which Iridium two-way communication (instead of Argos) has been implemented together with a variety of optical and biogeochemical sensors. The ProvBio-2 mission can be easily modified (almost in real time) by the operator thanks to Iridium telemetry. Basically two main modes of operation are used: the standard Argo mode, and the quadri-profile mode in which the diel cycle of optical (especially Chla and cp) and chemical (O2) properties is characterized. These diel characteristics are essential to quantify key biogeochemical fluxes, and such important processes as net community production and respiration. Eight PROVBIO-2 floats will be deployed (more).
The PROVAL float is mainly dedicated to the bio-optical characterization of water masses, especially in the context of the calibration/validation activities of ocean colour satellites. Two PROVAL floats will be deployed (more).