Presentation on theme: "Participants: CNR-ISAC Ifremer JRC-EC European COastal-shelf sea OPerational Observing and forecasting system Integrated Project WP3: “Better use of remote."— Presentation transcript:
Participants: CNR-ISAC Ifremer JRC-EC European COastal-shelf sea OPerational Observing and forecasting system Integrated Project WP3: “Better use of remote sensing and in situ observing systems for coastal/regional seas: Task 3.2: “Improved ocean colour algorithms and products for Case-II waters” Bay of Biscay Adriatic Sea
Validation of ocean products Ocean Colour products in the Bay of Biscay ECOOP WP3.2.1 In its use of Ocean Colour products, Ifremer has particularly developed the service to users, as encouraged by MarCoast (GMES Service Element funded by ESA) Therefore : -2 parameters are targeted for validation and assimilation in biological model : Chlorophyll and mineral SPM (for deriving K PAR ) - 3 parameters : SST, Chlorophyll and turbidity, are proposed for the operational monitoring required by the Water Framework Directive
Mean Chlorophyll-a MODIS 2003-2007 weeks 17&18 Mean Mineral SPM MODIS 2003-2007 weeks 17&18 Examples of products and the covered area
Validation at coastal station involved in coastal monitoring networks * * * * National in situ networks REPHY: phytoplankton & hydrology / Ifremer SOMLIT: hydrology / CNRS-INSU Some stations are shifted for the matchups
Validation of the chlorophyll concentration : The 15-day climatologies SeaWiFS (1998-2004) + MODIS (2005-2006) : the SRN Boulogne transect P1 (Coastal) P2 P3
Percentile 90% Cabourg Bell curve types for the chlorophyll seasonal cycle Mean Cabourg (nutrients from the Seine river) Mean Ouest Loscolo (nutrients from the Loire river) Percentile 90% Ouest Loscolo The validation of the satellite chlorophyll is not limited to the mean of the distribution but also to the variance. P90 is the parameter of interest for the WFD (eutrophic risk)
Percentile 90% Men er Roue Spring and autumn peaks for the chlorophyll seasonal cycle Mean Men er Roue Mean Men Du Percentile 90% Men Du
Same systematic validations for Turbidity (NTU) Cancale Ouest Loscolo Men er Roue Boyard Here the shift of 3 pixels has a strong effect on satellite turbidity (lower)
ECOOP – Adriatic Sea NB: Full reprocessing of the SeaWiFS European and global archive completed (Nov. 2007) http://oceancolour.jrc.ec.europa.eu The Adriatic Sea includes diverse water types, eutrophic to oligotrophic, for which the OC products are still affected by significant uncertainties. It is also covered by a wealth of field observations and is thus an ideal test bed for advanced remote sensing methods. The first year focused on validation of OC products.
A unique site and data set for validation of OC products Mélin & Zibordi, GRL, 2005 Mélin et al., JGR, 2006 Mélin et al., RSE, 2007a Clerici & Mélin, submit. Zibordi et al., IJRS, 2004, IEEE 2004, 2006, GRL, 2006, EOS 2006 Mélin & Zibordi, Appl. Opt., 2007 AAOT Acqua Alta Oceanographic Tower - aerosol optical thickness τ a (AERONET site; Jul. 1996 – present) - normalized water-leaving radiances L WN : in-water optical profiles (regular campaigns since 1995) autonomous above-water radiometry (May 2002 – present) - concentrations of optically significant constituents: Chla, TSM (regular campaigns since 1995) - inherent optical properties (IOPs): phytoplankton, CDOM, detritus absorption, particulate back-scattering (regular campaigns since 1995) Mélin et al., RSE, 2005, 2007b
Validation of SeaWiFS Radiometric Products Zibordi et al., GRL, 2006, EOS 2006 Mélin & Zibordi, Appl. Opt., 2007 Mélin et al., submit. SeaWiFS SeaPRISM Similar analyses have been conducted for MODIS and MERIS. SeaPRISM
Validation of Inherent Optical Properties Mélin et al., RSE, 2005, 2007b Phytoplankton absorption a ph (λ) Absorption by CDOM and NPP a dg (λ) Particulate back-scattering b bp (λ) encouraging results SeaWiFS
Validation of OC Chlorophyll data Aims/activities: 1.Assessment of the SeaWiFS and MODIS OC chlorophyll products in the Adriatic Sea with particular attention to the coastal waters (case 2) 2.Test different bio-optical algorithms for Chla (global and Mediterranean) to select the most appropriate one. 3.Define a strategy to improve the Adriatic CNR_ISAC operational regional products in coastal waters to be implemented for ECOOP TOP phase OC data are produced in NRT by CNR-ISAC in the framework of the Adricosm Project for environmental assesment and data assimilation in models http://gos.ifa.rm.cnr.it/adricosm/index.html
Po river discharge Ancona-Pescara Modis Aqua 6 th july 2004 The Adriatic Ocean Color CAL/VAL DATA SETS Po river discharge heavily influences the Western Adriatic Current turbid waters Projects/cruiseStationsAreaPeriod ADRICOSM_ER1245Nord Adriatic Sea2002-2006 REQUISITE3528Nord and Middle2004-2006 ADR06 150January 2006 DART06a 159 Middle AdriaticMarch 2006 DART06b 57 Middle Adriatic August 2006 TOTAL5139 In situ data set: 3 oceanographic cruises Repeated stations acquired by regional environmental agencies. 634 SeaWiFS case 2 water matchups 340 case 2 water Modis matchups
MEDOC4 OC4v4 R2=0.52 RMS=0.49 BIAS=0.32 R2=0.52 RMS=0.52 BIAS=0.34 OC4v4 (MUMM) MEDOC4 (MUMM) R2=0.42 RMS=0.49 BIAS=0.27 R2=0.46 RMS=0.49 BIAS=0.30 CARDER CLARK R2=0.49 RMS=0.44 BIAS=0.09 R2=0.44 RMS=0.50 BIAS=0.30 JRC JRC (MUMM) R2=0.45 RMS=0.43 BIAS=0.09 R2=0.41 RMS=0.40 BIAS=0.02 Validation of SeaWiFS Chlorophyll products 1.a general overestimation of the satellite Chla in all algorithms also when the regional Adriatic algorithm (JRC) is used 2.No improvements with MUMM atmospheric correction 3.Better results using Carder Algorithm (low Bias; uniform distribution)
OC3 MEDOC3 R 2 =0.42 RMS=0.44 BIAS=0.12 R2=0.44 RMS=0.44 BIAS=0.17 OC3 (MUMM) MEDOC3 (MUMM) R2=0.35 RMS=0.42 BIAS=0.10 R2=0.39 RMS=0.42 BIAS=0.13 CARDER GSM01 R2=0.84 RMS=0.24 BIAS=-0.15 R2=0.59 RMS=0.31 BIAS=-0.08 Validation of MODIS Chlorophyll products 1.Chla overestimation using standard (OC3) and Med (MedOC3) algorithms 2.No improvements with MUMM atmospheric correction 3.Better results using Carder Algorithm (highest R2) but small bias
Conclusions An specific case 2 chla algorithm is required for the Adriatic Sea In meantime the Carder’s algorithm should be introduced in the CNR-ISAC Adriatic operational processing chain to estimate the chla in Case 2 while MEDOC3 should be maintained for case 1 We need to develop of a method that produces a single chlorophyll map of the Adriatic with a different chlorophyll algorithm for case 2 and case 1 waters without introducing artificial gradients.
D126.96.36.199: Report on comparison between R/S and in-situ data (Adriatic Sea) D188.8.131.52: Report on comparison between R/S and in-situ data (Bay of Biscay) D184.108.40.206: Report on multi-sensor merging and dynamic bio-optical algorithm selection (Adriatic Sea) D220.127.116.11: Report on the merging technique between OC R/S and in-situ data (Bay of Biscay) European COastal-shelf sea OPerational Observing and forecasting system Integrated Project Deliverables and First-Year Status completed
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