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0 0 Robert Wolfe NASA GSFC, Greenbelt, MD GSFC Hydrospheric and Biospheric Sciences Laboratory, Terrestrial Information System Branch (614.5) Carbon Cycle & Ecosystems Joint Sciences Workshop, April 28 May 2, 2008 MODIS Land Collection 5 (and 6) MODIS Land Collection 5 (C5) Changes Used improved Land/Water mask and new Land Cover map based on 3 years of Collection 4 data Refined surface reflectance by adopting a dynamic aerosol model in atmospheric correction Reduced size and complexity of daily surface reflectance products Improved quality of the Land Surface Temperature by revising the day/night algorithm and improving the detection and filtering of cloud contaminated observations Increased resolution of BRDF/Albedo products to 500m; started production of the combined product every 8 days (with overlapped 16-day periods) Refined LAI/FPAR LUTs to improve numerical accuracy of the radiative transfer simulations; new 4-day combined product Added fractional snow algorithm in the snow product Added Burned area product Improved ancillary data interpolation to remove artifacts in the NPP product Reduced size of all Land products through HDF internal compression LAI/FPAR Comparison of Collection 4, Collection 5 and Canadian Center of Remote Sensing LAI and FPAR over Canada. MODIS data-days , 2003 (Source: Nikolay Shabanov, BU) Each collection represents an improvement in science quality C1 C3 C4 C5 Terra Aqua Terra Aqua Terra Aqua Reprocessed Forward processing MODIS Land Collections 0 Surface Reflectance The Collection 5 surface reflectance algorithm retrieves the aerosol model along with the aerosol optical thickness. This leads to less overcorrection in the surface reflectance product as illustrated in this example. (Source: Eric Vermote, UMD) 0 BRDF/Albedo The Collection 5 BRDF/Albedo product is being produced at a resolution of 500m which provides better spatial detail and will allow the production of a global Land Cover at 500m. (Source: Crystal Schaaf, BU) 0 Burned Area Collection 5 includes a monthly burned area product produced at 500m from Terra and Aqua. Burned Area 2003 dry season in Australia (March-November) (Source: David Roy, SD State) Collection 5 White Sky Albedo products in New England area at different resolutions March - April - May - June - July - August - September - October - NovemberC4 C5 Shortwave White-Sky Albedo, June 01 1km 500m C4 to C5 Transition C4 vs. C5 Example EVI and NDVI C5 data products are produced using the latest available versions of the science algorithms developed by the MODIS Land Science Team changes to fix known problems C5 science improvements C5 product format and product quality at the pixel level and granule level may differ from C4 To be reprocessed Now May 15 Beta Provisional Validated (Stage 1) Expected completi on date C5 has refined Lookup Tables (LUTs) for all biomes to improve numerical accuracy of radiative transfer simulations and to better match simulated reflectances and MODIS observations. Examples improvements are a reduction in over-stimulation of LAI and FPAR for needle leaf forest (below) and an increased rate of best quality retrievals. Collection 6 Planning MODIS Land Science Team is considering these questions for C6: 1.What changes (if any) do you feel are important to make to your algorithm? 2.What upstream algorithm changes would your algorithm benefit from? Also, what upstream changes would necessitate a reprocessing for your algorithm? 3.Based on 1 and 2, what are the significant scientific benefits from a C6 reprocessing for your algorithm? 4.Are there any other changes, such as product format changes, that are also needed? Why? Community C6 dates: June and July 2008 Community comment/review of proposed changes June 2009 to July 2010 Reprocessing occurs; 100% overlap with C5