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THE GLOBCARBON INITIATIVE. Stephen Plummer (IGBP@ESA), Olivier Arino (ESA), Freddy Fierens (VITO Consortium), Jing Chen (U. Toronto), Gerard Dedieu (CESBIO), Muriel Simon (SERCO),
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THE GLOBCARBON INITIATIVE Stephen Plummer (IGBP@ESA), Olivier Arino (ESA), Freddy Fierens (VITO Consortium), Jing Chen (U. Toronto), Gerard Dedieu (CESBIO), Muriel Simon (SERCO), Wolfgang Cramer (PIK), Philippe Ciais (LSCE), Shaun Quegan (CTCD), Martin Schultz and Judith Hoelzemann (MPI), Mike Raupach (GCP).
Carbon Data Assimilation To feed in to this Earth observation must deliver long time series estimates of global vegetation behaviour.
The ‘Champion’ Users Four key research institutes and one key programme involved to specify needs and use products: Will examine the use of fire statistics in the MOZART-2 Atmospheric Chemistry model Will examine the use of GLOBCARBON products in the Lund-Potsdam-Jena (LPJ) DGVM Will examine the use of GLOBCARBON products with the Sheffield DGVM (S-DGVM) Will examine the use of GLOBCARBON products within LSCE DGVM and Atmospheric Chemistry models Will examine the use of GLOBCARBON products within OpTIC model-data fusion experiment
General User Needs For Atmospheric Chemistry and Dynamic Global Vegetation Models: • There is a particular need for information on vegetation amount (ideally biomass or leaf area index), area burned, and vegetation temporal variability. • These should be global, in a consistent format, and all data products should be available from one place. • Consistency is more important than outright accuracy (within limits). • The products should be multi-annual with 5 years being the minimum but incorporating both average and extreme conditions e.g. El Ninõ. • Products should come with spatial heterogeneity information ideally at the highest available resolution. • The spatial resolution requirements are 0.5°, 0.25° and 10km. • The temporal resolution initially on a time step of 1 month but better higher, possibly bi-weekly.
Objectives The fully funded phase will: • develop a service quasi-independent of the original Earth Observation source. • focus on a system to estimate: • Burned area • fAPAR and LAI • Vegetation growth cycle • cover six complete years:1998 to 2003 (now up to 2007) • cover VEGETATION, ATSR-2, ENVISAT (AATSR, MERIS) • be applicable to existing archives and future satellite systems • be available at resolutions of ¼, ½ degree and 10km with statistics • build on the existing research experience
GLOBCARBON Processor Archive Burned Area Calibration Aerosols Cloud Detection ECMWF VGCP ACE DEM SMAC GOME/TOMS fAPAR, LAI SMAC Coefficients Band Normalise OPERATIONS (SADIST-2, ENVISAT Processor, CTIV) ATSR-2 AATSR MERIS VEGETATION Active fire BA Processor Curve fit Generate fAPAR LUT for LAI Land Cover
Leaf Area Index - 1 GLC’2000 ATSR-2 VEGETATION
Validation - Definition CEOS WGCV Definition the process of assessing by independent means the quality of the data products derived from the system outputs • Inter-comparison – not senso stricto validation because comparison with similar products which may or may not be more reliable than those under test • Absolute validation – sampling in situ and scaling up but major problems with approach and data availability
Inter-comparison • GLOBCARBON has overlap with a variety of similar products. Three are being considered for inter-comparison e.g. Boston-AVHRR-LAI, Boston/MODIS-LAI, Cyclopes. • The reliability test for LAI - three IGBP transects (Kalahari, Siberia and Amazonia) and temporally to one month (June, 2000). • 2 levels: • Direct comparison with MOD15A2 8-day composite products at 1km of resolution - FLUXNET ASCII sites • inter-comparison on the entire test transect area to allow a more significant statistical test. Monthly composites of MOD15A2 products (MOD15_BU) used.
Inter-comparison Results • MODIS: • 2 dates in June • 3x3 pixel mean around flux tower after re-projection, quality flag filter • GLOBCARBON: • 3x3 pixel mean over the corresponding week
Abs Validation - Criteria • The criteria for site sampling in GLOBCARBON are: • Size: the validation sites must correspond to the spatial resolution (1 km2 +/- 1). • Homogeneity: each site should be relatively homogeneous, i.e. the biophysical variable value must change only marginally when shifting the position of a 1 km2 pixel. • Topography: the area should be relatively flat. • Biome type: the variability of biomes and conditions encountered over the Earth’s surface must be adequately sampled. For GLOBCARBON samples should be acquired for each of the land cover classes of GLC’2000. • Number of sites: the number of sites used should comprise an adequate sampling of each of the qualifying land cover classes. • Season: coverage should include the range of vegetation conditions exhibited over the course of a growing season.
Abs Validation - Ideal CYTTARES: a network of sites representative of all biomes and conditions: 420 sites
Abs Validation - Ideal • Plan your validation (especially secure access to data) before you initiate your project • Adopt a standard protocol for the validation (e.g. CEOS Cal Val or GOFC/GOLD) • Use all available in situ and high resolution data following specific criteria
Abs Validation - GLOBCARBON • Plan your validation (esp access to data) before you initiate your project • GLOBCARBON is archive processing so validation must rely on existing databases e.g. VALERI, BigFoot, CCRS, Boston • Adopt a standard protocol for the validation (e.g. CEOS Cal Val or GOFC/GOLD • In GLOBCARBON it is presumed that the validation data provided respect the protocols • Use all available in situ and high resolution data • GLOBCARBON is an industrial contract – deadlines are real and only the data that are available within those times will be used. Final deadline for inputs is 15th June
Conclusions • To feed in to the Global Carbon Project Earth observation must deliver long time series, consistent estimates of global vegetation behaviour complete with accuracy/quality figures. • GLOBCARBON will deliver 10 complete years (1998 to 2007) of global vegetation products to the DGVM and atmospheric chemistry modelling community at resolutions of ¼, ½ degree and 10 km. • Timeline: • GLOBCARBON has now entered the operational production phase. • Validation and inter-comparison are key elements. All data must be available before 15th June 2005 (In the hands of the industrial contractor). • Validation and inter-comparison • Data still needed (LAI, burned area) – must be available by 15th June. • LAI maps derived from ETM or SPOT following standard protocols • Inter-comparison data – MODIS, BU-AVHRR, Cyclopes • Product Release (1998-2003): December 2005
Acknowledgements • Many thanks to all the people who have contributed data for the validation of GLOBCARBON LAI including: • R. Fernandes and CCRS colleagues • R. Myneni and the Boston team • W. Cohen and the BigFoot team • J. Privette for MODLAND and for ground data for SAFARI/LBA • J. Morisette for CEOS LPV image data • Frederic Baret. Marie Weiss and the VALERI team • P. Saccon, Joanneum/Bahia, Brazil
Please feed me data Thank You