Frédéric Achard European Commission – Joint Research Centre
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Transcript of Frédéric Achard European Commission – Joint Research Centre
Frédéric AchardEuropean Commission – Joint Research Centre
2nd GOFC-GOLD Workshop on reducing emissions from deforestation
Santa CruzBolivia16 -19 April 2007
Introduction:
The Joint Research Centre and tropical forest monitoring
JRC TREES 3 / FAO FRA 2010 projects:
Joint activities relating to the technical and practical issues for Reducing emissions from deforestation in developing countries
Example of regional forest cover change estimation:
The Congo Basin for the period 1990-2000
Part of the JRC’s work program is:
o to provide Scientific & Technical support to EU policies for o the Protection of the Environment
o to contribute to the EU Strategy on o Sustainable Development
The JRC has therefore been active in monitoring tropical forestsfor over 20 years
These activities have been carried out under the TREES project
- baseline inventory of the distribution of pan tropical forests
- methods to highlight areas of rapid change
- Quantification of pan tropical forest change for the period 1992 to 1997 using a sample of high resolution satellite data
Mapping
Monitoring
Measuring
TREES I / TREES II 1992 - 2002
In co-operation with FAO FRA :
- providing the input to FAO FRA RS Survey
- in collaboration with the FAO FRA regional / national networks
TREES-3 (2007 – 2013)
Forest change assessment: 1990 – 2000 - 2005 (2010?)
Phase I: tropical humid forests (start 2007)
Phase II: tropical dry forests and Eurasian boreal forests
Changes estimates to be valid at global & regional scales
FAO FRA 2010 RSS SCOPE & OVERALL PURPOSE
• Spatial distribution of forests at global & regional levels
• Land use change information (deforestation, fragmentation and forest degradation)
• Consistent information over time and space
• Independent monitoring system at global and regional level
• Complementary to national reporting and with close links to national monitoring systems
• Increased in-country capacity
FAO FRA 2010 RSS OUTPUTS
• Regional, biome and global monitoring of forests 1975-1990-2000-2005:– area change statistics– information on land use dynamics (including
deforestation, expansion of forests, fragmentation and forest degradation)
• Forest maps• A framework to support further monitoring of forests, land
use and the environment• Baseline data for research & modeling• Capacity building
IMPLEMENTATION
• Ca. 9 000 sample units, 4 dates• Centralized pre-processing & website• Standard methodology and classification• Regional training workshops• Interpretation by national / regional teams• Regional validation workshops• Centralized statistical analysis
A regular sample of sites based on the geographic grid across the tropics (an adapted scheme outside the tropics)
TREES-3 Forest change assessment
Systematic Sample with units at 1° x 1° lat/long
TREES-3 Number of sampling units
TROPICAL DOMAIN
Latin America Africa S& SE Asia
Central + Caribbean: 60 Humid: 451 South: 314
South America: 1168 Dry: 14731 Southeast: 421
Region: 1228 Region: 1924 Region: 735
Total: 3887
1 including full dry forest domain of Africa
• 20km x 20km sample units at each 1º lat-long grid intersection• based high spatial satellite imagery (Landsat TM, SPOT,
ASTER, similar..) for each date
a) forest cover change assessment within units of 20km x 20km
b) assessment of indicators for degradation processes (openings, roads..)
TREES-3 Forest change assessment
TREES-3 Land Cover LegendFAO LAND USE→:
↓TREES-3 LAND COVER:
Forest Other wooded
land
Other Land
With TC
Burnt Other……..
Water No Data
• Trees
• Mosaics Trees & other Land Cover
• Shrubs
• Burnt Areas
• Other Vegetated Cover
• Other Non-Vegetated Cover
• Water
• No-Data
Data download and site extraction
Site image control and pre-processing
Segmentation
Class labelling
Change layer generation
Internal consistency control
External control and added value
Automatic Box extractor (example PNG)
30 km X 30m boxes of year 2000 ETM data
30 km X 30m boxes of year 1990 TM data
Dry forest in NE Bolivia (Bosque Seco Chiquitano)
1990 2000Example of sample in Bolivia : 16 S / 61 W
Semi-automatic segmentation and change label for paired dates
Paired segmentation Automatic change label
1990
2000
TREES-3 Forest change assessment
Minimum mapping unit has implications for control
With MMU 0.5 ha: 1,500 polygons (average size 26 ha)
If MMU is too large : features are lost (e.g. burnt area)
With MMU 2 ha: 400 polygons (average size 94 ha)
Forest cover change assessment procedure
1. Image segmentation (automated)
2. Preliminary labeling of objects and changes (automated)
3. Verification and Adjustments of Labels- regional partner co-operation -
4. Validation - regional partner co-operation -
5. Adding forest and land use dimension (FAO FRA)- regional partner co-operation-
Dense forest
Degraded forest Mosaics Urban Savana
For. dense
For. DégradéeMosaïque Foret/Agriculture
Sol nu / urbain
Savane
Change matrice for the Congo Basin case study
Central AfricaForest area = 180.4 M ha
n average C.I.
101 2.20% 0.88%
104 1.48% 0.74%
98 1.94% 1.02%
97 2.73% 1.22%
400 2.08% 0.48%
Total deforestation over 10 years
1 degree X
1 degree
1/2 degree X
1/2 degree
Congo Brazzaville Dem. Rep CongoForest area= 22.2 M ha Forest area = 108.3 M ha
n average C.I. n average C.I.
14 0.86% 0.79% 68 2.45% 1.10%
16 0.67% 0.76% 68 1.95% 1.03%
11 0.03% 0.06% 65 2.72% 1.46%
15 1.02% 1.10% 67 2.72% 1.24%
56 0.69% 0.56% 268 2.45% 0.55%
Total deforestation over 10 years
1 degree X
1 degree
1/2 degree X
1/2 degree
Activity data :
Global and regional forest conversion rates
Methods for national forest conversion rates
Constant data :
National carbon stock estimate per forest type
Conclusions
Potential contribution of TREES-3 / FAO FRA 2010 to
the “reduction of emissions from deforestation” item
36
Mid-Decadal Global Land SurveyMid-Decadal Global Land Survey
Jeff MasekBiospheric Sciences Branch, NASA GSFC
Steve CovingtonAerospace Corporation / USGS
February 28, 2007
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Mid-Decadal Global Land Survey (MDGLS)Mid-Decadal Global Land Survey (MDGLS)
Follow-on to the GeoCover orthorectified global data sets (1975, 1990, and 2000 epochs) centered on 2004-2006
Partnership between USGS and NASA, in support of CCSPSupport global assessments of land-cover, land-cover change, and ecosystem dynamics (disturbance, vegetation health, etc)Landsat-5 TM and Landsat-7 imagery, with ASTER and EO-1 ALI data as needed
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Phase 1: identify all candidate scenes and ingest into the USGS archive (USGS lead)
Phase 2: Process selected data into an ortho-rectified dataset compatible with previous surveys (NASA lead)
Phase 3: Analyze data set to quantify trends in land cover and vegetation dynamics (NASA LCLUC)
MDGLS DevelopmentMDGLS Development
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What data are available? Landsat-7What data are available? Landsat-7
Green = Base ≤ 1% CC, Fill ≤ 5% CCYellowYellow = Base ≤ 5% CC, Fill ≤ 10% CC
3 month acquisition windows, 95% fill coverage
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Archived L7 Coverage Meeting SpecificationArchived L7 Coverage Meeting Specification
Global land coverage using L7 composite image pairswith >95% coverage
Prime ACCA> ,1Fill ACCA < 5
63%
No SuitableL7 Composite
Coverage18%
Prime>Fill < 20 ,5 8%
Prime>Fill < 10 ,5 5%
Prime>,1 Fill < 10
6%
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Combined Archived Coverage in EROS ArchiveCombined Archived Coverage in EROS Archive
GreenGreen = ETM+ 5%/10% CC FillYellowYellow = TM <10% CC in EROS ArchiveRedRed = TM = ??% CC in IC Archives
>91% of the P/R Locations Covered
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Phase 1 StatusPhase 1 StatusPhase 1: satellite tasking, ground station coordination, scene selection, data transfer, and ingest into the USGS archiveSince December 2005
Developed and implemented an MDGLS acquisition strategyDeveloped QA management tool and automated scene selection toolEstablished a network of 6 campaign stations to collect Landsat 5 data
4 have provided data (Kiruna, Moscow, Irkutsk, Maspalomas) 1 is under construction and will begin collections in early 2007(Chetumal)1 is in progress (Malindi)
Most International Cooperators have agreed to supply image data in support of the MDGLS Project
6 have provided metadata to USGS6 stations have confirmed Jpeg browse – for easier inspection
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Mid-Decadal Global Land Survey (MDGLS)
Phase I: Identify and Acquire L5 and L7 Data
Phase II: Process MDGLS Data
Phase III: Analyze MDGLS Dataset for Land Cover/ Land Cover Change
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• Establish MDGLS Product Specifications
•Select data source and scenes (where multiple options are available)
• Implement automated orthorectification at EROS
• Process selected data- Orthorectification- Gap-filling (for Landsat-7)- Product format
• Distribute MDGLS dataComplete dataset to be available Fall 2008
Phase II Tasks
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Data Source Selection: Status
Recommendation: - For cloud-free scenes (<2% CC): lean toward Landsat-7 ETM+- Cloudier scenes (2-10% CC): lean toward Landsat-5 TM- Humid Tropics: multiple acquisitions for compositing
Sensor choice must be balanced against acquisition date, overall cloud cover, and acquisition date of 2000 Geocover
- Optimization algorithm being developed to assist selection
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MDGLS Orthorectification
Need to reprocess previous GeoCover datasets in high-relief areas to maintain continuity with MDGLS
- model absolute error due to Geocover DEM choice- reprocess locations with errors >15m using SRTM
Use 2000 GeoCover chips as geodetic control, SRTM DEM for terrain correction
- L7 automated 1Gt processing available May 2007- L5 automated 1Gt processing available Spring 2008
Geodetic accuracy relative to 2000 Geocover of 30m RMSE (or better). Maximum absolute geodetic error of 100m.
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MDGLS Product Specification (Draft)
• UTM / WGS-84 projection• 14.25 / 28.5/ 57 meter resolution• Cubic Convolution resampling (1 step)• GeoTiff format• Orthorectified, Gap-filled
Processing by USGS EROS
FTP distribution of individual MDGLS scenes at no cost, with limited provision for bulk distribution of entire dataset (e.g. via hard disk transfer).