Urgent need of new tools to monitor and analyze the deep ocean processes.

Underwater Vision Profiler (UVP) mounted on an underwater observatory for long term monitoring of near sea bottom sedimentation and resuspension of particles and of near bottom zooplankton populations.

The combination of in situ imaging and measurement system (UVP) with geophysical and geochemical instrumentation will provide a complete picture of the long and short term near bottom events.

The use of the identical instrumentation for water column and benthic processes will for the first time link both domains on long time scales.

The Underwater Vision Profiler G.Gorsky, L.Stemmann, M.Picheral LOV (CNRS-UPMC)

L.Coppola (OOV, SOERE MOOSE)

The UVP records images of particles and organisms illuminated in slabs of water that have well-defined volumes ranging from 0.20 liters to 10 liters, depending on the UVP set-up.

The analysis of images provides quantitative information on the size and shape of objects in the field of vision of the UVP that can be used to calculate the distributions of particle size spectra, stocks and fluxes in real time.

In addition the large plankton (> 2 mm) is identified and its abundances reported.

The UVP is adapted for long term deployments in stand alone or instrumental platform mode.

Main housing:-Camera-Computer (real time processing)-Battery-Sensors-Electronics-Memory

Twin light system

Image volume(1 Litre)

Vision cone

UNDERWATER VISION PROFILER model 5

1100

mm

/ 3

0 K

g

• In situ particle counter ( > 50 µm ESD)• Zooplankton Imaging system

Time series of UVP data in Dyfamed (1992-1996)

Stemmann et al. DSRII (2002)

Observation of particles abundance, volume and dry weight from 0 to 1000m profiles.

Seasonal surface particles production and export to 1000m depth can be monitored.

Pulse of vertical flux in extreme events (Feb 1994) can eventually be observed.

Vertical distribution of seawater density, fluorescence and particles (ESD>0.11 mm) in three locations in the Eastern (site C, n=31), Central (site B, n=28) and Western (site A, n=28) Mediterranean Sea during the BOUM cruise in July 2008.

Vertical distribution of large organisms (>5 mm) detected by the UVP5 in the Western Mediterranean Sea during the BOUM cruise in July 2008. Copepods (a night, b day), Phaedorians (c night, d day) and radiolarians (e night and f day )

Vertical distribution of particles and zooplankton from the UVP during the BOUM cruise

night night night daydayday

Raddiolarians

Aggregates

Evolution in time of living and nonliving particles in the Pacific.

The first experience with a cabled subsea observatory equipped with an UVP will be undertaken in 2011 on the Ocean Technology Test Bed connected to VENUS in Saanich Inlet (BC, Canada). Waiting reply !!

The collaboration between LOV and University of Victoria, ASL Environmental Sciences VENUS/OTTB and ONCCEE will allow real time instrument monitoring, data acquisition and transmission to land and to the collaborating institutions. Include UVP and IODA (D.Lefevre, LMGEM)

Project: first step to deep sea observatory with Venus (ANR bilateral France-Canada)