ERC REFINE project: four state-of-the-art BGC floats deployed

In May and June, four new BGC floats have been deployed in the framework of the ERC REFINE project.

The LOV team deployed four BGC floats – some new Provor CTS5 Jumbo floats – in the Labrador Sea on board the R/V Celtic Explorer (Marine Institute, Galway, Ireland), through a campaign conducted as part of the “North-West Atlantic Biological Carbon Pump (NWA-BCP)” project.  They are dedicated to explore the Ocean Twilight Zone and address the key processes driving the Biological Carbon Pump.

 

Float preparation (on the left, © E. Leymarie/LOV) and deployment (on the right, © B. Dempsey/Dalhousie University).

 

The BGC floats were first tested at sea in March by the LOV team. © Thomas Jessin/LOV

New BGC floats featuring many innovations

For the first time, these four new BGC floats were equipped with the following innovative technologies:

  • an attenuation sensor (CRover) – a sensor typically used to measure the attenuation of light – is used here to measure the attenuation due to trapped sediments in order to calculate the rate of deposition of these sediments.  This sensor is associated for the first time with a multi-parking option at 200m, 500m and 1000m depth (the sensor is cleaned using a pump after each of these three steps),
  • the Underwater Vision Profiler (UVP6) embarking AI-based zooplankton recognition capabilities, according to pre-registered patterns for detected zooplankton specimens,
  • two hyperspectral Ramses radiometer from Trios to measure the downwelling and upwelling light fluxes (Ed / Lu) to determine reflectance.

The first profiles of hyperspectral measurement of the downwelling Irradiance (Ed)
and the upwelling radiance (Lu). © E. Leymarie/LOV

The REFINE project

REFINE aims to implement breakthrough in situ robotic process studies based on a new generation of highly instrumented jumboized profiling floats.

These deployments are the starting point of an expectedly long series of BGC Argo-based robotic process studies in nine key regions representative of the diversity of global oceanic biogeochemical conditions and their responses to climate change. Stay tuned!