Kim_WE3_T05_2.pptx

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Kim_WE3_T05_2.pptx

  1. 1. A METHODOLOGY TO SELECT PHENOLOGICALLY SUITABLE LANDSAT SCENES FOR FOREST CHANGE DETECTIONIGARSS 2011 , Jul, 27, 2011<br />Do-Hyung Kim, Raghuram Narashiman, Joseph O. Sexton, Chengquan Huang, John R. Townshend<br />Global Land Cover Facility, <br />University of Maryland - College Park<br />
  2. 2. CONTENT<br />1. Background<br />2. DATA<br />3. METHOD<br />4. RESULT<br />5. DISCUSSION<br />6. REFERENCE<br />2<br />
  3. 3. Background<br />Influence of phenology on forest change detection<br />example of path 116/ row 32 (Korea) <br />Profile based techniques by time series data can resolve the issue of influence of phenology on change detection performance (Coppin et. al., 2004)<br />3<br />Original Scene<br />Oct 7 2006<br />Change detection<br />False forest change by seasonality<br />Sep 2 1999<br />Change detection<br />Aug 28 2006<br />Aug 28 2006<br />Replacement Scene<br />
  4. 4. Background<br />Global Land Survey <br />Global, orthorectified, typically cloud-free Landsat imagery centered on the years 1975, 1990, 2000 and 2005 with a preference for leaf-on conditions(Gutman, 2008).<br />LARGE AREA SCENE SELECTION INTERFACE (LASSI)<br />Global Land Survey 2005 is a dataset which is selected using such an automated method, LARGE AREA SCENE SELECTION INTERFACE (LASSI) (Franks, 2002). <br /><ul><li>An automated scene selection method which specialized for forest cover change detection is needed</li></ul>Seasonality is not the only one parameter for LASSI.<br />GLS is not only for forest cover change analysis.<br />4<br />
  5. 5. DATA<br />MODIS data<br />MOD13C1 : 5km NDVI dataset for the years 2000-2009 (Hueteet. al., 2002)<br />Land cover data<br />MOD12C1 : 5km Land Cover dataset (Friedl el. al., 2002) consists of the IGBP classification system from which the % forest, % evergreen, % deciduous and % crop layers were extracted. <br />Landsat METADATA<br />Metadata of globally available Landsat scenes dating back from the 1970s to present(http://landsat.usgs.gov/consumer.php )<br />5<br />
  6. 6. METHOD<br />DATA process<br />6<br />S = pixels > 40% deciduous & number of samples > 15 from MOD13C1<br />When I = composite (1<= i <=23) and j = year (2000 <= j <= 2009)<br />Median value of the above samples for each ith composite at jth year <br />NDVIij= Median(S) <br />10 year norm, NORM at each i composite <br />NORMi= Median (NDVIij)<br />
  7. 7. METHOD<br />Filtering<br />7<br />NDVIij value which is greater or smaller than NORMi+- σ(NDVIij) is replaced by NORMi<br />NDVI<br />Composites<br />
  8. 8. METHOD<br />Peak growing season selection<br />SOP and EOP <br />8<br />
  9. 9. METHOD<br />Scene selection – web based app <br />9<br />User input<br />SOP, EOP<br />Search Conditions – Date/Month/Year, Quality, Cloud, Path/Row <br />SOP, EOP for each WRS2 tiles<br />Perform Search <br />Data Base update tool<br />Data Base<br />Landsat 7 ETM+ (SLC-on)Landsat 7 ETM+ (SLC-off)Landsat 1-5 TMLandsat 4-5 MSSLandsat 1-3 MSS<br />Metadata<br />UNZIP<br />Search results<br /> Shown as Table<br />
  10. 10. Deciduous forest Path/Rows<br />Number of Path/row<br />Deciduous<br />1546<br />7836<br />GLS <br />10<br />
  11. 11. RESULT<br />SOP, EOP<br />Temporal consistency <br />Trend compared to latitude and biome<br />GLS replacement scene<br />11<br />
  12. 12. 12<br />SOP of 10 year norm<br />
  13. 13. 13<br />EOP of 10 year norm<br />
  14. 14. 14<br />SOP variation from 1999 to 2007<br />Variation (date)<br />
  15. 15. 15<br />EOP variation from 1999 to 2007<br />Variation (date)<br />
  16. 16. Start of Peak by latitude and by Biomes<br />Temperate Broad Leaf<br />Tropical Dry Broad Leaf<br />
  17. 17. End of Peak by latitude<br />
  18. 18. GLS 2000 scenes need to be replaced<br />Number of Scenes<br />424<br />1546<br />7836<br />
  19. 19. GLS 2005 scenes need to be replaced<br />Numbers of Scenes<br />435<br />1546<br />7836<br />
  20. 20. Replacement scene selection<br /><ul><li>Browse through available scene list
  21. 21. Pick the best image based on visual observation
  22. 22. Criteria: Minimal cloud cover and within phenology bounds</li></li></ul><li>P17 R28: Canada Peak Season Range: 5/25/2002 – 9/30/2002<br />GLS<br />Replacement scene<br />Replacement scene date: 8/24/2001<br />GLS2000 date: 5/15/2002<br />
  23. 23. P22R49 (Guatemala)Peak Season Range: 6/10/1999 – 11/17/1999<br />GLS image: 12/4/1999<br />Replacement image: 8/6/1999<br />GLS date is just out of date range. Replacement scene has clouds. This is an example of replacement scene not being a better choice.<br />
  24. 24. Replacement Scenes<br />23<br />GLS 2000<br />284 Replacement / 424 scenes need to be replaced<br />GLS 2005<br />252 Replacement /435 scenes need to be replaced<br />
  25. 25. DISCUSSION<br />1. Snow effect<br />2. Scale issue<br />3. Selection of path/row with seasonality<br />4. Threshold selection<br />5. Validation against ground measurement<br />24<br />
  26. 26. Acknowledgement<br />This work has been carried out as part of the Global Forest Cover Change project, funded by the NASA MEaSUREs program (NNH06ZDA001N-MEASURES)<br />25<br />
  27. 27. Reference<br />A. Huete, et al., “Overview of the radiometric and biophysical performance of the MODIS vegetation indices,” Remote Sensing of Environment, vol. 83, no.1-2, pp. 195-213, Nov., 2002.<br />Friedl, M.A., et al., “The MODIS land cover product: multi-attribute mapping of global vegetation and land cover properties from time series MODIS data,” Proceedings of the International Geoscience and Remote Sensing Symposium (IGARSS), vol. 4, pp. 3199-3201, 2002<br />Coppin et. al., "Digital change detection methods in ecosystem monitoring: a review, “ IN T. J. REMOTE SENSING, 10 MAY, 2004, VOL. 25, NO. 9, 1565–1596<br />U.S. Geological Survey (2010, Dec. 30), Landsat Bulk Metadata Service. Available: http://landsat.usgs.gov/consumer.php <br />Gutman, G., Byrnes, R., Masek, J., Covington, S., Justice, C., Franks, S., and R. Headley, Towards monitoring land cover and land-use changes at a global scale: The Global Land Survey 2005, Photogrammetric Engineering and Remote Sensing, 74, 6-10, 2008.<br />Franks, S., Masek, J.G., Headley, R.M.K., Gasch, J., and Arvidson, T., Large Area Scene Selection Interface (LASSI). Methodology for selecting Landsat imagery for the Global Land Survey 2005, in press Photogrammetric Engineering and Remote Sensing. <br />26<br />

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