THE%20GLOBCARBON%20INITIATIVE

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THE GLOBCARBON INITIATIVE
Stephen Plummer (IGBP_at_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).
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Carbon Data Assimilation
To feed in to this Earth observation must deliver
long time series estimates of global vegetation
behaviour.
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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
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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.

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Background
The GLOBCARBON approach recognises the need to
produce services from multiple satellite datasets
because

• Satellites/sensors fail
• Sensors change and Programmes stop
• New sensors become available
• There is a need for long time series globally
• There is a need for continuity and accuracy

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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

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GLOBCARBON Processor
OPERATIONS (SADIST-2, ENVISAT Processor, CTIV)
VEGETATION
ATSR-2
MERIS
AATSR
Active fire
BA Processor
Curve fit
Generate fAPAR
LUT for LAI
Land Cover
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Leaf Area Index - 1
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Leaf Area Index - 2
ATSR-2
VEGETATION
Number of images used shown on same scale Max
VEGETATION 25 Max ATSR-2 6
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Leaf Area Index - 3
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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

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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.

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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
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Inter-comparison Amazon
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Inter-comparison Kalahari
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Inter-comparison Siberia
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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 Earths surface
  must be adequately sampled. For GLOBCARBON
  samples should be acquired for each of the land
  cover classes of GLC2000.
• 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.

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Abs Validation - Ideal
CYTTARES a network of sites representative of
all biomes and conditions 420 sites
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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

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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

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Validation - Reality
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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

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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

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Please feed me data
Thank You