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MODIS Land Product Subsets. Suresh K. Santhana Vannan , Robert B. Cook, Bruce E. Wilson, Lisa M. Olsen HDF and HDF-EOS Workshop XII October 15 – October 17, 2008 ORNL DAAC Oak Ridge National Laboratory Distributed Active Archive Center Oak Ridge, Tennessee, USA. What is MODIS.
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MODIS Land Product Subsets Suresh K. SanthanaVannan, Robert B. Cook, Bruce E. Wilson, Lisa M. Olsen HDF and HDF-EOS Workshop XII October 15 – October 17, 2008 ORNL DAAC Oak Ridge National Laboratory Distributed Active Archive Center Oak Ridge, Tennessee, USA
What is MODIS • MODerate Resolution Imaging Spectroradiometer • Hyper-Spectral sensor onboard two satellites (Terra and Aqua) • Terra MODIS and Aqua MODIS are viewing the entire Earth's surface every 1 to 2 days, acquiring data in 36 spectral bands, or groups of wavelengths • Data stored in HDF-EOS gridded file format Source : http://aqua.nasa.gov
MODIS is great! but …….. Users (Field researchers) have some inconveniences :
Accessibility • Data Format • Processing Time
What ORNL-DAAC offers? User community requested that we prepare MODIS Land Products in an easy-to-use format and size • To validate remote sensing products • To characterize field sites
Tools Used • hdp dumpsds from The HDF group • Customized for our need • MODIS Reprojection tool from LPDAAC • GDAL (Geospatial Data Abstraction Library) • Minnesota Map server • Custom Perl code
MODIS Subsets for Selected sites Data Formats Offered • ASCII – 7x7 km subsets • GeoTIFF – 25x25 km subsets
Subsetting and Visualization Tool for Any location on Globe Demo: http://daac.ornl.gov/modisglobal
1975 2001
1975 2001 2000 2008
MODIS Subsetting Web Service f(x) SOAP Client Server ################# ORNL DAAC MODIS Web service - Perl client#################use SOAP::Lite@params= SOAP::Lite -> service(‘WSDL_URL') -> xmlschema('http://www.w3.org/2001/XMLSchema') -> getsubset(lat,lon,product,start_date,end_date,size); MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_days,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,2007264203857,Clear_sky_days,NA,0.000,2 MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_nights,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,2007264203857,Clear_sky_nights,NA,0.000,254 …….
Scope • Tool for scientific research (Environmental Impact assessment, carbon budgeting, etc.) • Classroom education and projects for students • Time series, trend analysis • GIS overlay analysis • Statistical analysis (Across many years and across different land cover types) • Validation of MODIS products and other remote sensing products
Questions? Links • http://www.modis.ornl.gov/modis/index.cfm • http://daac.ornl.gov/MODIS/modis.html