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Global Studies of our Planet’s Vegetation

Global Studies of our Planet’s Vegetation. New SeaWiFS Land NDVI and Channels 9/97->now…. Precursor Land Data sets to MODIS aka the “warm-up act” for the main event. NOAA AVHRR -- July 1981 to the present… SeaWiFS -- September 1997 to the present …

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Global Studies of our Planet’s Vegetation

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  1. Global Studies of our Planet’s Vegetation New SeaWiFS Land NDVI and Channels 9/97->now…

  2. Precursor Land Data sets to MODISaka the “warm-up act” for the main event NOAA AVHRR -- July 1981 to the present… SeaWiFS -- September 1997 to the present … SPOT Vegetation -- May 1998 to the present … MODIS -- early 2000 to the present…

  3. Decadal trends in terrestrial vegetation 1992-2002 1982-2002 NOAA 14 AVHRR MODISes NOAA 11 AVHRR NOAA 9 AVHRR SPOT NOAA 7 AVHRR 1980 1985 1990 1995 2000 2005 2010 SeaWiFS NOAA-16 NPOES N-16 NOAA9

  4. NOAA Advanced Very High Resolution Radiometer (AVHRR) 1981-now… Visible, near IR, Thermal IR 1-km & 4-km data Only pre-Seawifs global time series data (<late 1997)

  5. NOAA AVHRR 8-km NDVI Data Set 20

  6. NOAA AVHRR 8-km NDVI Data Set

  7. NOAA AVHRR 8-km NDVI Data Set

  8. NOAA AVHRR 8-km NDVI Data SetSimple, few improvements since 1978

  9. NOAA AVHRR 8-km NDVI Data SetSimple, few improvements since 1978 ~80 kg, costs ~70 M$ each, ~20 built, also flies on TRMM

  10. AVHRR flies on the Polar-orbiting Meteorological Satellites 0730/1930 equator crossing series “early morning” satellites; and 1330/0130 equator crossing series “afternoon” satellites

  11. NOAA AVHRR 8-km NDVI Data Set Radiation

  12. NOAA AVHRR Channels 1 & 2 Ch 2 Ch 1 (Very broad or wide spectral bands)

  13. VIS/NIR/SWIR Band Comparison POLDER VGT SeaWiFS AVHRR MODIS MISR

  14. Ex post facto AVHRR Absolute Calibration

  15. NOAA AVHRR 8-km NDVI Data Set

  16. Aerosol, O3, Water Vapor, and Rayleigh Effects on AVHRR Ch1 & Ch 2

  17. Maximum Value Compositing No Assumptions

  18. NDVI Maximum Value Composites 8-km output bin from 4-km spatial resolution data at subpoint All orbits, all data processed, equal area map projection Scan Angle Restriction to +/- 40 degrees

  19. Maximum Value Compositing residual clouds 8-km, equal-area, maximum value ndvi composites, “seamless”

  20. Navigation Considerations “Three Cities of Dakar” “Migration” of Dakar 7/1 7/2 7/3 Dakar July 1, 2, and 3, 1981 NOAA-7 8-km grid cells Velocity = ~ 7 km/sec; thus a 0.15 second time error = ~1 km

  21. Solar Zenith Angle Effects 25N-25S

  22. Jorge’s new solar zenith angle correction Range w/o SZA Correction: 0.12 ndvi units Range w/ SZA correction: 0.05 ndvi units Wavelet decomposition/reconstruction technique Requires no land cover information a priori

  23. NOAA AVHRR 8-km NDVI Data Set Stratospheric Aerosol correction also required 1991 corrected Mt. Pinatubo, Philippines June 1991 Max. NDVI Effect 0.1-0.15

  24. NOAA AVHRR 8-km NDVI Data Set Stratospheric Aerosol correction also required Mt. Pinatubo El Chichon

  25. Space Shuttle Limb Photographs Before Mt. Pinatubo Eruption After Mt. Pinatubo Eruption

  26. NOAA AVHRR 8-km NDVI Data Set El Chichon (1982-1984) Mt. Pinatubo (1991-1994)

  27. NOAA AVHRR 8-km NDVI Data Set New and improved 8-km AVHRR NDVI data set

  28. Ready for Prime time:AVHRR NDVI match up to MODIS NDVI

  29. NOAA AVHRR 8-km NDVI Data SetMay-September NDVI trends

  30. Warmer Earth Greener NorthCompton Tucker, Dan Slayback, Jorge Pinzon NASA/GSFCRanga Myneni, Robert Kaufmann, Liming Zhou, Jiarui Dong BU Satellite record

  31. Warmer Earth Greener North Recent work using this new AVHRR data set • Zhou et al. 2001. Variations in Northern Vegetation Activity Inferred from Satellite Data of Vegetation Index During 1981 to 1999. J. Geophys. Res. 106:20069-20083. • Tucker et al. 2001/2002. Higher Northern Latitude NDVI and Growing Season Trends from 1982 to 1999. Int. J. Biometeorology (in press) • Myneni et al. 2001. A large carbon sink in the woody biomass of northern forests. Proc. Nat. Acad. Sci. (in press: 12/18/01). Boston University

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