1. J.L. Privette, NASA’s GSFC New CEOS WGCV Subgroup on Land Product Validation (LPV) Jeffrey L. Privette, NASA’s GSFC Jeffrey Morisette, SSAI

2. J.L. Privette, NASA’s GSFC LPV Vision Users of operational satellite products need to understand the products’ accuracy Product accuracy is determined through validation (independent measurements) Land product validation (Levels 3, 4) is in its infancy –expectations not formed –scientific exchange is beneficial –excellence sets precedent Best science will result if –all missions support validation and validation is on-going –uncertainty information determined through standard practice –algorithms are iteratively improved based on validation results –a global validation strategy for global change issues GOFC has been chosen as an initial programmatic focus for LPV activities – emphasis on moderate resolution, level 2 and 3 products.

3. J.L. Privette, NASA’s GSFC Global Observation of Forest Cover (GOFC) Part of the Global Terrestrial Observing System (GTOS) – contributing to the IGOS Carbon Theme Objective: to improve operational monitoring of land surface –includes all surface types, but with an emphasis on forests from the carbon perspective GOFC themes –Land cover –Biophysical Parameters (LAI/FPAR/NPP) –Fire Providing validated products is a high priority for GOFC

4. J.L. Privette, NASA’s GSFC LPV Action Items Consistency in definition of products –identify “common denominator” measurements needed to reliably estimate accuracies of slightly different products from different missions –international cooperation for rapid methods and data exchange/analysis Defining accuracy requirements –seek input from user communities (e.g. global change modelers) –accuracy targets will help define most efficient methods –validation in a user (science) context Information and Data Sharing exchange –promote data sharing and provide open-release guidelines –combine central archives, distributed/linked sites (WGISS leadership) –standard level of data reduction

5. J.L. Privette, NASA’s GSFC Validation ‘Test’ Sites Focus for in-situ and satellite data collection that can support validation Quantity –varies with: algorithm, product type, end-user, and within-class variability of a landcover Global Representivity Temporal distribution and “invariance” –solar angles, phenological changes, etc. dictate sampling frequency Size –a function of sensor pixel, pointing accuracy, PSF, statistical significance of a set of pixels at one site)

6. J.L. Privette, NASA’s GSFC EOS Land Validation Core Sites SATELLITE DATA Multiple sensors, various scales, subsetted over the site and WWW accessible. Ancillary/GIS Layers such as… - elevation - land cover - reference layer (with political boundaries, airports, water bodies) Scientific Networks such as AERONET and FLUXNET data Field and airborne data WWW accessible Graphic courtesy of the BigFoot program

7. J.L. Privette, NASA’s GSFC Examples of Emerging International Validation Networks and Activities Networks –Canadian LAI network (11 sites) –European VALERI (6 sites) –EOS Land Validation Core Site Network (23 sites) –Miscellaneous mission-specific networks (e.g. ASTER) –LPSIM Site Inventory (comprehensive list) –WGCV test site dossier (65+) http://spsosun.gsfc.nasa.gov/calval/query.html Possibility of enhancing dossier to include LPV sites Activities –NASA’s Prototype Validation Exercise (PROVE) –DISCover Global Land Cover Validation –CSIRO ASTER Validation (Prata/Hook)

8. J.L. Privette, NASA’s GSFC Majura Valley Kioloa Moreton Bay Lake George Batt Reef Cooper Creek Mossman Daintree Cape Tribulation Townsville Reef Lake Argyle Goldsworthy Lake Eyre Mt Fitton Uardry Tinga tingana Tanjil Bren Amburla Port Hedland Kakadu Panorama Hyperion Sites Other CSIRO Sites Key Toolabin Kunoth X band sites Thangoo Lake Frome CIGSN Sites Endevour Reef Ray Merton Earth Observation Centre http://www.eoc.csiro.au

9. J.L. Privette, NASA’s GSFC Landsat scenes used for LAI validation across Canada Summer, 1998 & 2000 1 2 3

10. J.L. Privette, NASA’s GSFC Japanese Global Land Imager Mongolia Observation Area Site 1

11. MODLAND (NASA) VALERI (CNES) VALERI (EC?) VALERI (China?) Distribution of EOS and VALERI Sites

12. J.L. Privette, NASA’s GSFC Sampling Issues Sampling design and local scaling issues –inconsistency in “point measurement” design/scaling –destructive sampling vs. indirect instruments –community requests for handbook of “best practices” e.g., expanded BigFoot manual protocols of how measurements are taken, documented, sequence of activities, use of “black box” software from instrument vendors Field Instruments –recommendations –estimating products from surrogate parameters –characterization (specifications) –calibration

13. J.L. Privette, NASA’s GSFC VALERI Sampling/Scaling SPOT image of the Romilly VALERI site (Red : XS3, Green: XS1, Blue: XS2). Right: the local LAI2000 measurements (the stars) organized along a 20m long cross. The vertical lines represent the row direction.

14. J.L. Privette, NASA’s GSFC Validation Data Use Issues Comparing a satellite product with field data –Mismatch in spatial scale of sample vs. product –Aggregation and scaling methods are fairly unsophisticated Evaluating multidate, composited or aggregated products with instantaneous ground samples –Constructing error budgets and reporting statistics in a way that meets user community needs Estimating uncertainties globally from sample sites –Within LC class variability –Extrapolation method/usefulness is application-dependent Independence of “calibration” sites (tuning) from validation sites

15. J.L. Privette, NASA’s GSFC Activity 1: LAI Product Intercomparison 12-18 month pathfinder Comparison of operational and research LAI products at “non-calibration sites” Initial emphasis on coarse-resolution sensors Leverage Year 2000 field campaigns Shake-out for more rigorous, longer-term and multiproduct comparisons

16. J.L. Privette, NASA’s GSFC Sites Providing Data for LAI Intercomparison * LAI and satellite data collected in Year 2000, as of 23 October 2000 *

17. J.L. Privette, NASA’s GSFC Activity 2. Fire Products Validation Joint activity with GOFC Fire Team Builds on Expresso, SAFARI, SCAR campaigns Characterization and intercomparison of Active Fire products –DMSP, AVHRR, ATSR, MODIS, GOES –Comparison with ground based fire data bases World Fire Web Validation Development of a network of representative long term Fire Validation sites Field protocols for data collection for Burned Area validation using high resolution data –ATSR, MODIS, AVHRR –GOFC Miombo Network pathfinding activity

18. J.L. Privette, NASA’s GSFC Activity 3. Land Cover Product Validation Focus on global land cover classification, continuous fields and land cover change products –AVHRR,VEGETATION, MODIS, ATSR, GLI, VIIRS Builds on DISCover Validation approach and activity Use of high resolution data for validating global products –Landsat/SPOT –IKONOS Under development

19. J.L. Privette, NASA’s GSFC LPV Subgroup Organization Chair: Jeff Privette (NASA) –Chairmanship tenure: 3-5 years Deputy Chair: Jeff Morisette (SSAI) Implementation: –Annual, topical workshops with designated workshop leaders: Reports, recommendations. –Community activities design to address issues/problems in validation

20. J.L. Privette, NASA’s GSFC Topical Validation Workshops Planned Workshops 2001 –GOFC: LAI/FPAR Intercomparison -- Frascati, Italy --June 2001 (Privette/Baret/Leroy) –GOFC: Fire Validation – Lisbon, Portugal -- July 2001 (Justice/Gregoire) Proposed Workshop (TBD) –GOFC Land cover and change products validation (Skole/Gunawan) Suggested Future Topics for Land Product Validation Workshops –GOFC: Biomass estimation accuracy (incl. VCL, SAR) –Albedo / BRDF (combined with annual BRDF meeting) –Snow cover/available water –Land surface temperature –Geostationary product validation in 2002 (MSG, GOES, Triana, etc.)