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.

1. 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

2. 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

3. MODIS is great!
but ……..
Users (Field researchers) have some inconveniences :

4. Volume

5. Accessibility
Data Format
Processing Time

6. 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

7. 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

8. MODIS Subsets for Selected sites
MODIS Products offered at ORNL-DAAC
Data Formats Offered


ASCII – 7x7 km subsets
GeoTIFF – 25x25 km subsets
Surface Reflectance
Surface Temperature
Land Cover
Vegetation Phenology
NDVI / EVI
LAI / fPAR
Net Photosynthesis
Annual NPP
Albedo (calc)
Reflectance – BRDF Adjusted

10. Subsetting and Visualization Tool for Any location on Globe
Demo:
http://daac.ornl.gov/modisglobal

12. Case Study: Deforestation in Amazon

13. 1975
2001

14. 1975
2001
2000
2008

15. Dec 31 2010

16. Jan 1 2011

17. MODIS Subsetting Web Service
f(x)
Client
################
# 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);
SOAP
SOAP
Server
MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_
MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_
days,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,200726
days,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,200726
4203857,Clear_sky_days,NA,0.000,2
4203857,Clear_sky_days,NA,0.000,2
MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_
MOD11A2.A2003001.h26v05.005.2007264203857.Clear_sky_
nights,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,20072
nights,MOD11A2,A2003001,Lat37.7Lon110Samp1Line1,20072
64203857,Clear_sky_nights,NA,0.000,254
64203857,Clear_sky_nights,NA,0.000,254
…….
…….

18. 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

19. Questions?
Links
 http://www.modis.ornl.gov/modis/index.cfm
 http://daac.ornl.gov/MODIS/modis.html