MERIS data QWG, ESRIN, Frascati, April 2008 BOUSSOLE: status of activities in April of 2008 David ANTOINE Laboratoire dOcéanographie de Villefranche MERIS, March 4, 2003, © ESA

MERIS data QWG, ESRIN, Frascati, April 2008 Outline A few reminders about the project Facts Science exploitation Cal / val operations Conclusions / perspectives

MERIS data QWG, ESRIN, Frascati, April 2008 How is the Earth changing and what are the consequences for life on Earth? How is the global Earth system changing? What are the primary causes of change in the Earth system? How does the Earth system respond to natural and human-induced changes? What are the consequences of changes in the Earth system for human civilization? How well can we predict future changes to the Earth system? The answers to these questions rely on Cal/Val Extracts from a NOAA/NASA/NIST workshop « Achieving satellite instrument calibration for climate change » Ohring et al., 2007, EOS Trans AGU

MERIS data QWG, ESRIN, Frascati, April 2008 Thats what is done for altimetry Extrait du site AVISO/CLS,

MERIS data QWG, ESRIN, Frascati, April st comment / message Maintaining calibration of ocean color sensors is a major activity that cannot be neglected or considered just as a basic duty of space Agencies Researcher must be involved closely with space Agencies This is a key to answer correctly to present questions on the present and future changes of ocean biogeochemistry and their responses to global environment changes This is not so obvious.. Nothing is granted in this domain

MERIS data QWG, ESRIN, Frascati, April 2008 BOUSSOLE: motivations - Science objectives : short-term changes in IOPs and AOPs, relationships between both, role of CDOM, seasonal and inter-annual changes, bidirectionality of the ocean reflectance... - Operational objective : vicarious calibration of ocean color observations from space, and validation of the level-2 geophysical products (e.g., chlorophyll, normalized radiances). Establishing a time series of inherent and apparent optical properties (IOPs and AOPs), with two parallel objectives :

MERIS data QWG, ESRIN, Frascati, April 2008 BOUSSOLE: strategy - A deep sea mooring, collecting data on a continuous basis - Monthly cruises for collecting data that are not accessible to the mooring (vertical profiles, water sampling), as well as for servicing the mooring - A coastal AERONET station, providing the necessary information about the aerosol properties, which are a central element of the vicarious calibration process Combination of 3 elements :

MERIS data QWG, ESRIN, Frascati, April 2008 The site (43°22N; 7°54E) Deep (2400 m) Case 1 waters

MERIS data QWG, ESRIN, Frascati, April 2008 Water at BOUSSOLE are permanently Case 1 waters Buoy data Morel & Maritorena, 2001 Upper limit for Case 1 waters

MERIS data QWG, ESRIN, Frascati, April 2008 The range of bio-optical properties at BOUSSOLE is representative of global Case 1 waters Thick line : BOUSSOLE Thin line and thin dotted line : SeaWiFS global or Med Sea only Gray : NOMAD

MERIS data QWG, ESRIN, Frascati, April m -4 m Acquisition en rafale (1 minute à 6 Hz) : Possibilité de filtrer leffet de linterface pour sapprocher de la valeur réelle de K d ou K u, et donc de réaliser une meilleure extrapolation vers la surface Ombrage minimal par la bouée elle-même 25 mètres radiomètres

MERIS data QWG, ESRIN, Frascati, April 2008 BOUSSOLE buoy: some illustrations

MERIS data QWG, ESRIN, Frascati, April 2008 Measurements, instruments: Monthly cruises Vertical profiles: T, S, O 2, chlorophyll fluorescence (CTD) E d & E u at 13 l (Satlantic SPMR/SMSR), Secchi disk Phytoplancton pigments (HPLC) phytoplancton absorption (filters) CDOM absorption Total absorption & 9 (Wetlabs AC9) Backscattering coefficient (Wetlabs eco VSF) CDOM fluorescence (Wetlabs CDOM WetStar). Surface : Dry weight of particles (SPM) AOT (CIMEL CE-317 or SIMBADA). Lw determined from above the surface (SIMBADA) Photometer CE-318 : AOT, aerosol types AERONET

MERIS data QWG, ESRIN, Frascati, April 2008 Measurements, instruments : buoy italics: evolutions in 2008 E d, E u, L 7 (Satlantic & 9 m (+ reference above the surface) (L u hyperspectral from 350 to 800 nm, resolution 2 nm) PAR sensor Attenuation 660 nm (4 & 9 m) phytoplankton fluorescence (4 & 9 m) Backscattering 443 et 560 (9 m) (442, 488, 555 & 620 nm) Temperature, salinity, pressure Tilt & heading of the buoy Mooring cable strain

MERIS data QWG, ESRIN, Frascati, April 2008 Work at sea 70 monthly cruises (since july 2001; Tethys-II) 15 buoy deployment / recovery cruises (ship: castor 02) 40 opportunity cruises (1-2 days) for verifications / repairs / cleaning etc… 17-days AOPEX cruise (Suroit, Août 2004) Buoy deployments Over 1460 days since september of 2003, the buoy was continuously deployed (except Janv. Fev 2004), and has functioned during 1250 days, i.e., a 85% success rate

MERIS data QWG, ESRIN, Frascati, April 2008 But 2008 came.. Mid January: ship collision: the buoy is recovered immediately (the upper superstructure that host the instrumentation) One month later: the mooring line breaks: the lower part of the buoy (main floatation) + the mooring line are recovered At the end: no loss of instrumentation Buoys are being checked, repaired and prepared for redeployment The instrument suite is being checked by Satlantic Redeployment is planned in June At the end, this is a 5-months interruption of the data flow…

MERIS data QWG, ESRIN, Frascati, April 2008 Since January of

MERIS data QWG, ESRIN, Frascati, April 2008 BOUSSOLE: publications Antoine, D. M. Chami, H. Claustre, F. DOrtenzio, A. Morel, G. Bécu, B. Gentili, F. Louis, J. Ras, E. Roussier, A.J. Scott, D. Tailliez, S. B. Hooker, P. Guevel, J.-F. Desté, C. Dempsey and D. Adams. 2006, BOUSSOLE : a joint CNRS-INSU, ESA, CNES and NASA Ocean Color Calibration And Validation Activity. NASA Technical memorandum N° 2006–214147, 61 pp. Voss, K., A. Morel and D. Antoine, Detailed validation of the bidirectional effect in various Case 1 waters for application to Ocean Color imagery, Biogeosciences,, 4, Morel A., H. Claustre, D. Antoine, B. Gentili, Attenuation and reflectance properties within the visible and near-UV spectral domains, as determined in south Pacific waters, and compared with those in some other oceanic zones, Biogeosciences, 4, Antoine, D., P. Guevel, J.-F. Desté, G. Bécu, F. Louis, A.J. Scott and P. Bardey, The « BOUSSOLE » buoy – A new transparent-to-swell taut mooring dedicated to marine optics : design, tests and performance at sea, sous presse à Journal of Atmospheric and Oceanic Technology. Antoine, D., F. DOrtenzio, S.B. Hooker, G. Bécu, B. Gentili, D. Tailliez andA. Scott, Assessment of uncertainty in the ocean reflectance determined by three satellite ocean color sensors (MERIS, SeaWiFS, MODIS) at an offshore site in the Mediterranean Sea (BOUSSOLE project), accepté à Journal of Geophysical Research. Bailey S., S.B. Hooker, D. Antoine, J.P. Werdell and B. Franz, Vicarious calibration of ocean color satellite remote sensors: An analysis of sources and assumptions, soumis à Applied Optics. Antoine D., and P. Gernez, Field characterization of wave-induced underwater light field fluctuations, en préparation pour Journal of Geophysical Research, Oceans. Banzon, V., D. Antoine, C. Kuchinke, K. Voss, H.R. Gordon and R.H. Evans, Application of a dust-correction algorithm for SeaWiFS in the Mediterranean Sea : when is it appropriate ? en préparation pour Journal of Geophysical Research, Oceans. Dubuisson P., R. Frouin, L. Dufôret, D. Dessailly, K. Voss & D. Antoine, Estimating aerosol altitude from reflectance measurements in the O2 A-band, en préparation pour Applied Optics.

MERIS data QWG, ESRIN, Frascati, April 2008 Cal / val operations for: - ENVISAT – MERIS, ESA - SeaWiFS, NASA - MODIS-A, NASA - PARASOL – POLDER3, CNES In a « near » future: - Sentinel3 – OLCI, ESA (2012) Also, likely for: - OCM-2, ISRO - CNSA sensors - Future geostationary sensor above europe (CNES..)

MERIS data QWG, ESRIN, Frascati, April 2008 Cal / val operations Identification of the « blue overestimation » for MERIS. Antoine, D., F. DOrtenzio, S.B. Hooker, G. Bécu, B. Gentili, D. Tailliez and A.J. Scott, 2008, Assessment of uncertainty in the water-leaving reflectance determined by thfree satellite ocean color sensors (MERIS, SeaWiFS, MODIS-A) at an offshore site in the Mediterranean Sea (BOUSSOLE project), Journal of Geophysical Research, Oceans, in press MERIS SeaWiFS MODIS

MERIS data QWG, ESRIN, Frascati, April 2008 Comparaison of vicarious cal gains obtained with MOBY, BOUSSOLE & NOMAD Bailey, S., S.B. Hooker, D. Antoine, B.A. Franz, and P.J. Werdell, Sources and assumptions for the, 2008, vicarious calibration of ocean color satellite observations, Applied Optics Vol. 47, No. 12, Cal / val operations

MERIS data QWG, ESRIN, Frascati, April 2008 « Qualité des produits de réflectances marine issus de POLDER3 / PARASOL », présentation faite le 18 décembre 2006 au CNES par F Steinmetz et P.-Y. Deschamps MAY 2006 NOV 2006 AOT<0.1 AOT>0.1 Cal / val operations

MERIS data QWG, ESRIN, Frascati, April 2008 Characterization of uncertainties in products (chlorophyll for instance) from different missions Needed before data from different sensors can be merged (e.g., GlobCOLOUR) Merged products MERIS / MODIS / SeaWiFS, july 2002

MERIS data QWG, ESRIN, Frascati, April 2008 In summary Development & qualification of a new measurement platform, dedicated to marine optics Set up of a staff & scientific teams The system is quasi-operational, with two sister buoys and moorings continuous acquisition Data production as requested by space Agencies (cal/val) Scientific exploitation is being developed International recognition is achieved The use of the data is developing regularly The project will continue in the coming years

MERIS data QWG, ESRIN, Frascati, April 2008 Thank you

MERIS data QWG, ESRIN, Frascati, April 2008 People (LOV+OOV+external partnerships) P.I. (L.O.V., Villefranche sur mer) Equipe Optique marine et télédétection David ANTOINE, Etudiants, post-Docs Pierre Gernez (thèse P6) Terry OBree (post Doc; démarrage septembre 2007) Equipe technique (L.O.V. et O.O.V., Villefranche sur mer) 100% BOUSSOLE Guislain BECU, Responsable campagnes en mer, traitement des données ( ) Enzo VELLUCCIidem, depuis octobre 2007CDD CNES et ESA Contributions variables (10 à 50%), partagées avec les autres activités du LOV Bernard GENTILI,Traitement des données Francis LOUIS,Electronique, divers Joséphine RAS,Mesures HPLC et absorption sur filtre Dominique TAILLIEZ,CTD + IOPs, campagnes mensuelles David LUQUET,Plongée Partenariats entreprises Pierre GUEVEL,ACRI-st-Genimar, conception bouée, calculs hydro Jean-François DESTE,ACRI-st-Genimar, ingénierie bouée Philippe BARDEY,ACRI-st, Expertise Ludovic BOURG, Grigor OBOLENSKY, ACRI-st, traitement données MERIS Alpha CAMARA,Avance Conceptuelle, conception bouée, calculs de structure Cyril DEMPSEY, Satlantic Inc., instrumentation optique Darrell ADAMS,Satlantic Inc. instrumentation optique

MERIS data QWG, ESRIN, Frascati, April 2008 Other people, collaborations Equipe scientifique (L.O.V., Villefranche sur mer) Equipe Optique marine et télédétection Marcel BABIN,fluorescence du phytoplancton Annick BRICAUD,IOPs (absorption) Malik CHAMI,étalonnage indirect, polarisation Hervé CLAUSTRE,IOPs, proxys biogeochimiques, nouvelles plateformes Fabrizio dORTENZIOCal/val, relations physique-optique André MOREL,AOPs Collaborations Nationales P. Y. DESCHAMPS et al.LOA, Univ. LilleAbove-water vs below-water, PARASOL H. LOISEL et al.ELICO, WimereuxIOPs C. MOULINLSCE, ParisProjet PFT-Med (LEFE-CYBER) Collaborations Internationales Stanford B. HOOKERNASA/GSFCOptics protocols, cal/val operations Kenneth J. VOSSUniv. MiamiBidirectionalité Robert FROUINScripps Corrections atm., PAR Dave SIEGELUCSBCDOM Chuck TREESNURC, La SpeziaCampagne 2008 (SORTIE)

MERIS data QWG, ESRIN, Frascati, April 2008 Funding Angencies Agence Spatiale Européenne Centre National dEtudes Spatiales National Aeronautics and Space Administration of the USA Centre National de la Recherche Scientifique Institut National des Sciences de lUnivers Observatoire Océanologique de Villefranche sur mer Université Pierre et Marie Curie