Slide 1 - ORNL DAAC for Biogeoch

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Slide 1 - ORNL DAAC for Biogeoch Powered By Docstoc
					                              Web and Web Services based tool that provides subsets and visualization of MODIS land products to facilitate
                                                           land validation and field site characterization1

                                                                            Suresh K. Santhana Vannan (, Robert B. Cook, Bruce E. Wilson
                                                                     Environmental Sciences Division, Oak Ridge National Laboratory2, Oak Ridge, Tennessee 37831-6407
                                                                                         AGU Fall Meeting, San Francisco, California, December 14-18, 2009
 Introduction                                                                                                                       MODIS Land Product Subsets for Selected Field Sites                                                                        MODIS Land Product Subsets for any location
         MODIS (Moderate Resolution Imaging Spectroradiometer) sensor data are highly useful for                                                                                                                                                               The ORNL DAAC also offers subsets of MODIS Land Products in ASCII and GeoTIFF format for
 field research. However, the volume of MODIS data and the complexity in data format makes                                                                                                                                                                     user-selected areas (from one pixel up to 201 x 201 km) worldwide and for any time period during
 MODIS data less usable in some cases.                                                                                                                                                                                                                         the MODIS record.
         To solve this usability issue, the Oak Ridge National Laboratory (ORNL) Distributed Active
 Archive Center (DAAC) prepares and distributes subsets of selected MODIS Land Products in a                                      MODIS ASCII and GeoTIFF Subsets are
 scale and format useful for field researchers. MODIS subsets are provided for more than 1,000                                    available for over 1,000 field sites                                                                                         •    User places an order through
 sites across the globe. The subsets are offered in tabular ASCII format and in image GeoTIFF                                     worldwide. Sites are included upon                                                                                                a Web interface
 format. Time series plots and grid visualizations to help characterize field sites are also provided.                            willingness to share in situ site data (quid                                                                                 •    The tool will send an email
         The ORNL DAAC also offers the capability to create user-defined subsets for any location                                 pro quo). Subsetted data (original size: 25                                                                                       message containing a URL
 worldwide. The custom subsetting tool provides subsets from a single pixel up to 201 x 201 km for                                x 25 km) are received from the MODIS                                                                                              where the output can be
 user-defined time range. Statistics, time series plots, ASCII and GeoTIFF files for the customized                               processing stream and converted at the                                                                                            accessed
 subsets are also distributed through this tool.                                                                                  ORNL DAAC into ASCII (7 x 7 km) and                             1,147 Sites                                                  •    Subset generation including
         A Web service based MODIS subsetter is also provided for users to obtain MODIS subsets                                   GeoTIFF (25 x 25 km) formats.                                                                                                     generation of time series data
 programmatically. The Web service is a machine to machine interface that facilitates integration of                                                                                                                                                                file, graphs, and statistics
 Web service into workflow.                                                                                                                                                                                                                                         takes 10 to 60 minutes
                                                                                                                                                                                                                                                                    (depends on area, time                                                                                                                                                                                                                                         period, and product)
                                                                                                                                                                                                                                                                                                                                           User selects site from map, picklist or enters coordinates

 Background                                                                                                                                                                                                                                                                                                                                                                                                           Tool provides Google
                                                                                                                                                                                                                                                                                                                                                                                                                      map,3D-Google Earth
                                                                                                                                                                                                                                                                                                                                                                                                                      and Landsat image of
 The ORNL DAAC archives and distributes terrestrial biogeochemical
                                                                                                                                                                                                                                                                                                                                                                                                                      the sinusoidal area
 dynamics data collected as part of the NASA's Earth Observing                                                                    Data visualization and download options for Walker Branch Watershed- Tennessee
 System (EOS) Program. ORNL DAAC's data sets are primarily from                                                                                                                                                                                                                                                                                                                                                       selected. The elevation
 ground-based field investigations and augmented by data collected                                                                                                                                                                                                                                                                                                                                                    of the center
 through remote-sensing techniques. The types of data held by the                                                                 ASCII (Tabular) Subsets                                                                                                                                                                                                                                                             coordinate is also
 ORNL DAAC are Field Campaign, Land Validation, Regional and Global                                                                                                                                                                                                                                                                                                                                                   provided.
 Data, and Model Products.

 MODIS is a key sensor aboard the Terra and Aqua satellites. Terra MODIS and Aqua MODIS are
                                                                                                                                                                                                                                                               MODIS NDVI subset data presented as time series, with average and standard deviation shown for
 viewing the entire Earth's surface every 1 to 2 days, acquiring data in 36 spectral bands, or groups
                                                                                                                                                                                                                                                               pixels in area selected.
 of wavelengths. These data will improve our understanding of global dynamics and processes
 occurring on the land, in the oceans, and in the lower atmosphere.
                                                                                                                                                                                                                                                                                                                                                                                                            • Plots generated on the fly                                                                                                                                                                                                                                                                                                                                                                                for a user selected time
                                                                                                                                                                                                                                 Center Pixel
                                                                                                                                                                                                                                 Mean Value of Pixels                                                                                                                                                       period
                                                                                                                                                                                                                                 Percent of Pixels that meet
                                                                                                                                                                                                                                 QC Criteria                                                                                                                                                                • Stacked time series for all
                                                                                                                                                                                                                                                                                                                                                                                                            years for inter-annual data
                                                                                                                                                                                                                                                                        Center Pixel Value
                                                                                                                                                                                                                                                                        Mean Value of All Pixels
                                                                                                                                                                                                                                                                        Percent of Pixels that meet QC Criteria
                                                                                                                                                                                                                                                                                                                                                                                                            •Statistics are provided for
                                                                                                                                                                                                                                                                                                                                                                                                            all pixels in selected area
                                                                                                                                  ASCII Example: NDVI for Walker branch site.                                                                                                                                                                                                                               that have the same land
                                                                                                                                                                                                                                                                                                                                                                                                            cover class as center pixel.
 MODIS Subset: Details                                                                                                                   Time-series graphs: NDVI Time series for Walker
                                                                                                                                         Branch FLUXNET site.
 •      Products Subsetted: Terra and
        Aqua MODIS                                            MODIS Products Subsetted
 •      Sinusoidal Projection                                                                                                                                                                                                                                                                                                                                                         Composite grid visualization showing
 •      2000 to present                                                                                                                                                                                                                                                                                                                                                               deforestation in the Amazon between
                                                                      Surface Reflectance                                                                                                                            Composite Period Grid Plot:                                                                                                                                      2000 and 2008. The above image is
 •      8-day, 16-day, and annual
                                                                                                                                                                                                                     LAI grid for Walker Branch site for                                                                                                                              from MODIS terra MOD13Q1, 160.25
        composite periods
 •      250-m, 500-m, or 1000-m                                      Surface Temperature                                                                                                                             composite period June 17th 2000                                                                                                                                  x 160.25 km subset with QC filter
                                                                                                                                                                                                                     to June 24th 2000                                                                                                                                                applied.
        resolution (depends on product)
 •      Documentation provided to                                            Land Cover                                                                                                                              Users also have the option of
        describe the subsetted products;                                                                                                                                                                             choosing their own quality control            NDVI for Composite Period Jul 11th 2000        NDVI for Composite Period Jul 11th 2008

        links are provided to full                        Phenology (available winter 2009)
                                                                                                                                                                                                                                                                            (MOD13Q1 2000193)                              (MOD13Q1 2008193)
        documentation at MODIS Web                                                                                                                                                                                                                                                                                                                                                                               Data Download
                                                                              NDVI / EVI
                                                                                                                                                                                                                                                                                                                                                                                                     • ASCII (tabular CSV) subset file
                                                                                                                                                                                                                                                                                                                                                                                                     • GeoTIFF file (In Sinusoidal
 Data Processing                                                              LAI / fPAR                                          GeoTIFF (Image/GIS) Subsets
                                                                                                                                                                                                                                                                                                                                                                                                     projection or Geographic coordinate
 • MODIS fixed site subsets                                                                                                       • GeoTIFFs can be viewed in
   reformatted from HDF-EOS into
                                                          Gap-Filled and Smoothed LAI/fPAR                                          WebGIS Tool (in Sinusoidal
                                                                                                                                                                                                                                                                                                                                                                                                     • Statistical data of the subset

   ASCII/GeoTIFF format using LP                                                                                                    Projection) along with other map
   DAAC’s MODIS Reprojection Tool,                                     Net Photosynthesis                                           layers
   Geospatial Data Abstraction Library                                                                                            • Site / Product / Date                                                                                                      The tool provides land cover grid (IGBP classification for Collection 5 shown) of the area, along
   (GDAL) tools and custom Perl code                                         Annual NPP                                             combinations can be selected                                                                                               with an estimate of heterogeneity (Shannon Diversity Index). Detailed documentation is
 • Subsets for the MODIS Global                                                                                                     using a picklist and downloaded                                                                                            provided for each file.
   subsetting tool are generated                                                                                                    for a date or all dates
   directly from MODIS tiles using
                                                             Albedo (Model and Calculated)                                        • A WebGIS Tool can be used to                                                                                     
   customized code obtained from The                                                                                                filter values or determine values
   HDF Group (THG)                                             Reflectance – BRDF Adjusted                                          of individual pixels
 • Visualization of data is done using                                                                                            • The GeoTIFF images are                                                                                                     MODIS Global Subsetting Web Service (SOAP)
   Perl code and Perl graphics library                                                                                              automatically color scaled to
                                                                                                                                    improve interpretation                                                                                                     Simple Object Access Protocol (SOAP)
                                                                                                                                                                                                                                                               based Web Service for programmatically
     ORNL DAAC MODIS Subsets provide data in a format and size that is designed for field
                                                                                                                                                                                                                                                               accessing MODIS subsets.
     researchers. The availability of these subsets dramatically reduces the amount of time needed to
     process data. For example, to obtain four years of NDVI data for a 7 x 7 km area from MODIS                                  MODIS NDVI GeoTIFF Images on                                                                                                 •   Programmatically retrieve subsets                                               Client                                                          SOAP
     tiles, users would have to download approximately 10 GB of data. Extracting 7 x 7 km area from                               a MODIS land cover(IGBP)                                                                                                     •   Real time data delivery                                                          ################                                                       MOD11A2.A2003001.h26v05.005.20072642038
                                                                                                                                                                                                                                                                                                                                                    # ORNL DAAC MODIS Web service - Perl client
     nearly 200 MODIS tiles (One tile for every 16- day period) would require time and resources.                                 background for sites in Europe                                                                                               •   Integrate with client side tools                                                 #################
                                                                                                                                                                                                                                                                                                                                                    use SOAP::Lite

     The ORNL DAAC however delivers the subset in few minutes and the size of the data delivered is                                                                                                                                                            •   Connect with workflow software
                                                                                                                                                                                                                                                                                                                                                    @params= SOAP::Lite
                                                                                                                                                                                                                                                                                                                                                      -> service(‘WSDL_URL')
                                                                                                                                                                                                                                                                                                                                                      -> xmlschema('')
     less than 100 MB for a similar subset. The data are offered in tabular files and in GIS compatible                                                                                                                                                                                                                                               -> getsubset(lat,lon,product,start_date,end_date,size);              y_nights,NA,0.000,254

     format to allow users to import the data into spreadsheet and GIS processing packages.
1This   study was supported by the NASA’s Earth Observing System Data and Information System. 2 Managed by the University of Tennessee-Battelle LLC under contract 2052-V131-09 with the U.S. Department of Energy

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