Global land cover validation activities Martin Herold (FSU Jena) & Mark Friedl (UBoston) CEOS Cal/Val land subgroup (land cover) Global Observations of Forest Cover and Land Dynamics With contributions from Curtis Woodcock (UBoston), Olivier Arino (ESA), Pierre Defourny (UCL), Steve Stehman (SUNY) CEOS WGCV LPV Focus Group Lead Meeting, Missoula, Montana, June 15, 2009

Activities 1.Political initiatives driving observation progress and needs for validation –Observing land cover as ECV –Independent quality assessment and integration 2.Global land cover observations and accuracy assessments –MODIS and GLOBCOVER –Best use of existing reference datasets 3.Coordinated effort to develop LC validation database 4.Accuracy assessment for fine-scale land cover change and area estimates –Post-Kyoto agreement and best practices

GLOBCOVER (2005/6) Dataset release: September 2008

GLOBCOVER validation 4 More than 4300 validation points interpreted by int. experts Blue points: Globcover project (3835 points) + Gond’s set (n~80) (including 225 double interpretation by 2 experts) Brown points: IMWI data (403 points) Global area weighted accuracy: ~73 % based on 3167 reference points Validation report available ~ 15. October 2008

MODIS Collection 5 Land Cover (2001-present)

MODIS Land Cover Validation 1860 Training Sites – Cross Validation

Notion of a “Best Currently Available” Land Cover Map Need for comparative assessment and synthesis products Combine the strengths of multiple sources of land cover data across multiple extents and resolutions (national, regional and global sources) Based on what is learned in the validation exercise A transparent and community endorsed activity LCCS compatibility is critical Simple guidance criteria: more accurate is better finer spatial resolution is better more thematic detail is better

Thematic standards Reference database (GLC2000) Comparative validation & assessment Probability

Operational lc validation framework Degree of usability and flexibility Updated valid./change Validation of new products Design based sample of reference sites In-situ global Primary validation LCCS-based Interpretation (Regional Networks) Reference database: statistically robust, consistent, harmonized, updated, and accessible Updated interpretations Time Comparative validation Existing global LC products Legend translations Product synergy Data reprocessing Link to regional datasets

Operational lc validation framework Effort serves purpose for estimating: –Individual map accuracy / best available map –Area of land-cover classes or land-cover change Sampling design: –10 km by 10 km block (Landsat – MODIS) –Flexible to increase sample size to provide precise country or region specific estimates Response design: –Reference data (i.e. SPOT) interpreted by regional experts (i.e. GOFC-GOLD networks) using LCCS classifiers Analysis design: –Error matrix for each map and region –Estimates of class area –Supplementary accuracy information on land-cover composition and landscape pattern

Current Status – Early Stages of Stratification and Sample Design Workshop tentatively planned for late July in Boston