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MODIS (Moderate Resolution Imaging Spectroradiometer) sensor data are highly useful for field research. However, the volume of MODIS data and the complexity in data format makes MODIS data less usable for some communities. To expand the use of MODIS data beyond traditional remote sensing specialists, the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) prepares and distributes subsets of selected Land Products in a scale and format useful for undergraduate students and field researchers. MODIS subsets are provided for more than 1,000 sites across the globe. The subsets are offered in tabular ASCII format and in GIS compatible GeoTIFF format. Time series plots and grid visualizations to help characterize field sites are also provided. In addition to offering subsets for fixed sites, the ORNL DAAC also offers the capability to create user-defined subsets for any location worldwide. The MODIS Global subsetting tool provides subsets from a single pixel up to 201 x 201 km for user-defined time range. Statistics, time series plots and GIS compatible files for the customized subsets are also distributed through this tool. Users can also programmatically retrieve the subsets through a SOAP based Web Service.
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MODIS Land Product SubsetsMODIS Land Product Subsets
Suresh K. Santhana Vannan, Robert B. Cook, Bruce E. Wilson, Lisa M. Olsen
HDF and HDF-EOS Workshop XIIHDF and HDF-EOS Workshop XIIOctober 15 – October 17, 2008October 15 – October 17, 2008
ORNL DAACORNL DAACOak Ridge National LaboratoryOak Ridge National Laboratory
Distributed Active Archive CenterDistributed Active Archive CenterOak Ridge, Tennessee, USA Oak Ridge, Tennessee, USA
What is MODISWhat is MODIS MODMODerate Resolution erate Resolution IImaging maging SSpectroradiometer pectroradiometer
Hyper-Spectral sensor onboard two satellites (Terra and Aqua)Hyper-Spectral sensor onboard two satellites (Terra and Aqua)
Terra MODIS and Aqua MODIS are viewing the entire Earth's surface every Terra MODIS and Aqua MODIS are viewing the entire Earth's surface every 1 to 2 days1 to 2 days, acquiring data in , acquiring data in 36 spectral bands36 spectral bands, or groups of wavelengths, or groups of wavelengths
Data stored in Data stored in HDF-EOS HDF-EOS gridded file formatgridded file format
Source : http://aqua.nasa.gov
MODIS is great! MODIS is great! but ……..but ……..
Users (Field researchers) have some inconveniences :Users (Field researchers) have some inconveniences :
Volume
AccessibilityAccessibility
Data FormatData Format
Processing TimeProcessing Time
What ORNL-DAAC offers?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 sitesMODIS Subsets for Selected sites
Data Formats OfferedData Formats Offered ASCII – 7x7 km subsets ASCII – 7x7 km subsets GeoTIFF – 25x25 km subsetsGeoTIFF – 25x25 km subsets
MODIS Products offered at ORNL-DAAC
Surface ReflectanceSurface Reflectance
Surface TemperatureSurface Temperature
Land CoverLand Cover
Vegetation Phenology
NDVI / EVINDVI / EVI
LAI / fPARLAI / fPAR
Net PhotosynthesisNet Photosynthesis
Annual NPP Annual NPP
Albedo (calc)Albedo (calc)
Reflectance – BRDF AdjustedReflectance – BRDF Adjusted
Subsetting and Visualization Tool for Any location on Globe
Demo:Demo:http://daac.ornl.gov/modisglobal
Case Study: Deforestation in Amazon
1975
2001
1975
2001
2000 2008
Dec 31 2010
Jan 1 2011
MODIS Subsetting Web Service MODIS Subsetting Web Service
################# 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,0.000,2MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_nights,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,2007264203857,Clear_sky_nights,NA,0.000,254…….
MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_days,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,2007264203857,Clear_sky_days,NA,0.000,2MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_nights,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,2007264203857,Clear_sky_nights,NA,0.000,254…….
f(x)f(x)
Client ServerSOAPSOAP
ScopeScope Tool for scientific research (Environmental Tool for scientific research (Environmental
Impact assessment, carbon budgeting, etc.)Impact assessment, carbon budgeting, etc.) Classroom education and projects for studentsClassroom education and projects for students Time series, trend analysis Time series, trend analysis GIS overlay analysisGIS overlay analysis Statistical analysis (Across many years and Statistical analysis (Across many years and
across different land cover types)across different land cover types) Validation of MODIS products and other remote Validation of MODIS products and other remote
sensing productssensing products
Questions?Questions?
LinksLinks
http://www.modis.ornl.gov/modis/index.cfm http://daac.ornl.gov/MODIS/modis.html
