MODIS Land Status. Robert Wolfe NASA GSFC Code Land Cover Land Use Change Meeting. April 1, 2009

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1 1 MODIS Land Status Robert Wolfe NASA GSFC Code Land Cover Land Use Change Meeting April 1, 2009

2 2 Shifting MODLand Emphases Algorithm Development and Testing, Initial Coding (starting 1997) Instrument Performance Evaluation algorithm revision/recoding Product Testing and Beta Generation > Provisional Distribution Initial PR and Outreach / Code Revision First Major Reprocessing > Product QA and Validation Stage 1 Validated Product Distribution > Feedback Increased Outreach Science/Application Completion of Stage 2/3 Validation Collection 5/6 Reprocessing Current Emphasis Science Team initiated in 1988 Instrument Monitoring New ATBD s?

3 3 MODIS Land Science Team Science Team Members Product R. Wolfe Geolocation E. Vermote Surface Reflectance C. Schaaf Albedo Z. Wan, S. Hook Surface Temperature D. Hall, J. Maslanik Snow Cover M. Friedl Land Cover, Phenology/Dynamics I. Csiszar, C. Justice Active Fires, Burned Area J. Townshend Vegetation Continuous Fields D. Hall, J. Maslanik Ice Surface Temperature A. Huete, R. Myneni Vegetation Indices, LAI/FPAR S. Running GPP/NPP, Evapotranspiration S. Ustin, A. Lyapustin, S. Liang, J. Stroeve, R. Write, X. Xiao New products or analysis

4 C5 Completed Spring 2008! MODIS Collection 5 (C5) completed Spring 2008 Many product improvements (i.e. 500m BRDF, burned area) C5 LST product has emissivity issue in barren areas C4.1 (C4 algorithm with C5 L1 inputs) being produced for 2007 forward C4.1 and C4 form a continuous time series C6 expected to fix issue C5 Land Cover and Phenology/Dynamics being processed Land 500 m for years 2000 to 2005 now available; 2006/07 release expected this summer Vegetation phenology almost ready to be released for 2000 to 2005; 2006/07 release expected this summer C5 VCF expected this summer 4

5 MODIS Land Distribution Files (1000/Month) Volume (TB/Month) ,000 3,500 3,000 2,500 2,000 1,500 1, LP DAAC MODIS Land Volume Distributed LP DAAC MODIS Land Files Distributed C4 C5 Both C4 C5 Both (LP DAAC Land Products Only Doesn t include NSIDC Snow/Ice Products) 5

6 Validation Status Product Stage Key Data Method MOD09 - Surface Aeronet, Field - 2 Reflectance Landsat ETM Scaling MOD10/ 29 - Snow - 2 Volunteer, AWS - Sea Ice - 2 Landsat ETM, ASTER Scaling MOD11 - LST - Emissivity - 2 Field Direct MOD12 - Landcover Landsat ETM - Scaling - Phenology Volunteer field data - Direct MOD13 - NDVI - 2 Landsat ETM, ASTER, SPOT - EVI - 2 Aeronet, Fluxnet, Field Scaling MOD14 - Active Fire - 2 Landsat ETM, ASTER Scaling MOD15 - LAI - 2 Landsat ETM, SPOT, IKONOS, AVIRIS Scaling / - ƒpar - 1 Fluxnet, field / campaigns Direct MOD17 - GPP - 2 Landsat ETM Scaling / - NPP - 2 Fluxnet, field / campaigns Direct MCD43 - BRDF/ Landsat ETM, ASTER, IKONOS - 1 Albedo BSRN, Aeronet, Fluxnet, AWS Scaling MOD44 - VCF Landsat ETM, IKONOS, Quickbird VCC Field Scaling MCD45 - Burned Area - 1 Landsat ETM, ASTER Scaling (Nightingale et al., 2009) 6

7 Land Validation Sites of validation activities for most of the Land products. The majority of validation activities occurred in North America, though operational scientific networks such as BSRN, Aeronet and Fluxnet, in addition to satellite-product inter-comparisons. Validation Stages: 1. Product accuracy has been estimated using a small number of independent measurements obtained from selected locations and time periods and ground-truth/field program efforts. 2. Product accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts. 3. Product accuracy has been assessed, and the uncertainties in the product well-established via independent measurements made in a systematic and statistically robust way that represents global conditions. (Nightingale et al., 2009; Morisette et al. 2006) 7

8 MODIS Albedo and Reflectance Anisotropy (BRDF) (Schaaf, Boston University) Validation with POLDER-3/PARASOL Nov 2005 to Oct

9 New PI data set: MODIS Evapotranspiration University of Montana 9

10 10 Amazon forests green-up in the dry season EVI (MODIS) Rainforest greens up Huete et al., 2006, GRL LAI (MODIS) Converted land drys out Myneni et al., 2007, PNAS dry sunny season rainy season

11 Amazon rainforest more productive and highly resilient to short term climatic anomalies such as the intense drought in 2005 TRMM anomaly MODIS EVI anomaly Rainforest was resilient to short term climatic anomalies Saleska, Didan, Huete, Rocha, 2007, Science 11

12 Global MODIS NPP vs. Inverted CO2 inter-annual growth rates Correlation between MODIS NPP and inverted CO 2 annual growth rate anomalies NPP by GMAO ~2006 p < NPP by NCEP ~2006 p < University of Montana 12

13 C6 Plans Time needed for community to evaluate and use C5 (C6 will complete 3 years after C5) For some products C5 will be the last reprocessing VI, LAI Greater community outreach planned for C6 Montana Vegetation Workshop, June C6 test data sets will be available for review Expected completion in Jan years of MODIS/Terra and 8.5 years of MODIS/Aqua No data-gap C5 will continue until reprocessing completes 13

14 14 C6 Time-line May 2008 June 2008 Dec 2009 to Apr 2010 Mar 2009 to Dec 2010 June to Dec 2009 Jan 2010 Dec 2010 List of L1 C6 changes defined List of Land C6 changes defined Delivery of Land C6 algorithms Science testing of Land C6 algorithms Period for community comment/review of changes Start of Land C6 Reprocessing completed C5 Forward processing will continue until after the C6 Reprocessing completes

15 15 New 250m L/W Mask for C6 Improved inland water bodies Next step dynamic mask? Ready for VIIRS (Jan launch)

16 C6 Changes Highlights (1/5) 1. Surface Reflectance (Vermote) Continuous aerosol QA flag Improvement to clouds and shadows (with LDOPE) BRDF coupling in aerosol retrieval and surface reflectance 8-day BRDF corrected reflectance (with gap fill) 2. Vegetation Indices (Huete) (non planned) 3. BRDF/Albedo (Schaaf) Improve backup algorithm Improve quality fields and move to L2G-lite Proposed: 2 250m and 4-day frequency (based on 16- days) 4. LAI/FPAR (Ranga) (none planned) 16

17 C6 Changes Highlights (2/5) 5. Net Photosynthesis (Zhao/Running) Biome-Look-UP-Table (BPLUT) update Finer spatial resolution GMAO data 6. Vegetation Continuous Fields (Carroll/Townsend) Changes dependent on Surf. Refl. changes and final C5 VCF product (will finish this summer) Proposed: VCF moving to 250m 7. Thermal Anomalies/Fire (Giglio/Csiszar) Refine internal cloud mask heavy smoke Fix false alarms in Amazon Fix scan edge cloud/water confusion with Fire 8. Burned Area (Roy/Justice) Include active Fire product 17

18 C6 Changes Highlights (3/5) 9. Land Cover/Dynamics (Friedl) Land Cover Migrate to hieratical LCCS compliant classification scheme Stabilize classification across years Improve difficult classes Phenology/Dynamics Proposed: Move to 250m product (see NBAR) Use 8-day product Improved snow screening and gap filling Asymmetric sigmoid fitting 10. Snow/Sea-ice (Hall) Collaborate with BU to improve snow albedo Create a cloud-free product (gap filled) Improved use of cloud mask 18

19 C6 Changes Highlights (4/5) 11. Land Surface Temperature (Wan) Remove cloud contaminated values from L2 (in addition to L3) product Update LUT for split-window algorithm (focus on arid and semi-arid regions) Improve land-cover based emissivities (focus on barren areas) 12. Generic changes (Devadiga) Use one cloud mask (not both MOD09 and MOD35) Fix L2G-lite and use in downstream algorithms (not L2G(-heavy) or MODAGG) Eliminate 1km products when 500m is available 19

20 C6 Changes Highlights (5/5) 13. L1B and Geolocation (Wenny/Xiong and Wolfe) L1B Dead detector handling change (fill, not interpolated) A0/A2 (gain) update Thermal bands Response vs. Scan-angle (RVS) update (detector dependent) New polarization information (from Oceans; particularly for recent Terra) Geolocation improved terrain correction and 500m geolocation possibly incorporate new L/W mask and 500m terrain model 14. L2G, L2G-lite (Wolfe) Any fixes needed so L2G-lite can be used with down-stream algorithms (inc. any additional Surf. Refl. fields) Use 500m geolocation in 500m/250m products 15. New proposed standard products (ATBDs in process) Leaf water content (Ustin) Alternate Surface Refl./Albedo/NBAR/BRF (Lyapustin) 20

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