1. Geography 372 Fall 2003November 4, 2003 1 Remote Sensing of the Land Surface: High Spatial Resolution Michael D. King & Compton J. Tucker Outline  Land remote sensing at high spatial resolution  Satellite sensors enabling remote sensing of land cover at high spatial resolution –Landsat RBV, MSS, TM, ETM+ –Spot HRV –Terra ASTER  Orbital characteristics  Instrument characteristics –Spacecraft, spatial resolution, swath width, sensor characteristics, and unique characteristics  Land properties as observed by Landsat and ASTER

2. Geography 372 Fall 2003November 4, 2003 2 Characteristics of Landsat Missions

3. Geography 372 Fall 2003November 4, 2003 3 The orbital period of a satellite around a planet is given by where  0 = orbital period (sec) R p =planet radius (6380 km for Earth) H=orbit altitude above planet’s surface (km) g s =acceleration due to gravity (0.00981 km s -2 for Earth) Definition of Orbital Period of a Satellite

4. Geography 372 Fall 2003November 4, 2003 4 Landsat-1, -2, and -3 Observatory Configuration Solar array Multispectral Scanner (MSS) Return Beam Vidicon (RBV) cameras Data collection antenna

5. Geography 372 Fall 2003November 4, 2003 5 Spectral Sensitivity of the Four Landsat MSS Bands  Bands compared with the spectral sensitivity of the three emulsion layers used in color and color infrared film

6. Geography 372 Fall 2003November 4, 2003 6 Landsat MSS Operating Configuration

7. Geography 372 Fall 2003November 4, 2003 7 Ground Resolution Cell Size versus MSS Pixel Size

8. Geography 372 Fall 2003November 4, 2003 8 Landsat 5 TM EO-1 Hyperion Landsat 7 ETM+ EO-1 ALI Green Vegetation Senescent vegetation Bare soil Band 2 Band 3 Band 4 Band 5Band 7 Band 1

9. Geography 372 Fall 2003November 4, 2003 9 Satellite systems and sensors

10. Geography 372 Fall 2003November 4, 2003 10 Sun-Synchronous Orbit of Landsat-4 and -5

11. Geography 372 Fall 2003November 4, 2003 11 Successful Launch

12. Geography 372 Fall 2003November 4, 2003 12

13. Geography 372 Fall 2003November 4, 2003 13 Landsat 7 Swathing Pattern

14. Geography 372 Fall 2003November 4, 2003 14 Swath Progression Pattern

15. Geography 372 Fall 2003November 4, 2003 15 Landsat-4 and -5 Observatory Configuration High gain antenna Multispectral Scanner (MSS) Solar array Thematic Mapper (TM) S-band antenna

16. Geography 372 Fall 2003November 4, 2003 16 Thematic Mapper Optical Path and Projection of Detector IFOVs on the Earth’s Surface

17. Geography 372 Fall 2003November 4, 2003 17 Schematic of TM Scan Line Correction Process (b) Correction for satellite motion (a) Uncompensated scan lines (c) Compensated scan lines

18. Geography 372 Fall 2003November 4, 2003 18

19. Geography 372 Fall 2003November 4, 2003 19 Side-Lap Composting, no interpolation

20. Geography 372 Fall 2003November 4, 2003 20 Side-Lap Composting, no interpolation

21. Geography 372 Fall 2003November 4, 2003 21 Before After Multi-pass compositing, no Interpolation

22. Geography 372 Fall 2003November 4, 2003 22 Landsat’s Bands  Landsat collects monochrome images in each band by measuring radiance & reflectance in each channel. When viewed individually, these images appear as shades of gray

23. Geography 372 Fall 2003November 4, 2003 23  The human eye is not sensitive to ultraviolet or infrared light –To build a composite image from remote sensing data that makes sense to our eyes, we must use colors from the visible portion of the EM spectrum— red, green, and blue Color Composites

24. Geography 372 Fall 2003November 4, 2003 24  This image was produced using the red, green, & blue bands from Landsat’s Thematic Mapper –Note the washed out appearance of the landscape due to atmospheric effects ‘True Color’ Landsat TM Image R=0.66 µm G=0.56 µm B=0.48 µm

25. Geography 372 Fall 2003November 4, 2003 25 “False Color” Landsat Image  These images were produced using near-infrared, red, and green bands –Notice how vegetation is more clearly distinguished from nonvegetation Channels 4, 3, 2Channels 5, 4, 2

26. Geography 372 Fall 2003November 4, 2003 26 San Francisco Onion Skin Animation

27. Geography 372 Fall 2003November 4, 2003 27 Landsat 7 Launched April 15, 1999

28. Geography 372 Fall 2003November 4, 2003 28 Enhanced Thematic Mapper Plus (ETM+)  NASA & USGS, Landsat 7 –launched April 15, 1999 –705 km polar orbit, descending (10:00 a.m.)  Sensor Characteristics –7 spectral bands ranging from 0.48 to 11.5 µm –1 panchromatic band (0.5-0.9 µm) –cross-track scan mirror with 185 km swath width –Spatial resolutions: »15 m (panchromatic) »30 m (spectral) –Calibration: »5% reflectance accuracy »1% thermal IR accuracy »onboard lamps, blackbody, and shutter »solar diffuser

29. Geography 372 Fall 2003November 4, 2003 29 Thematic Mapper Optical Path and Projection of Detector IFOVs on the Earth’s Surface

30. Geography 372 Fall 2003November 4, 2003 30 Landsat 7 Goals & Objectives  Land use and land cover change –Agricultural evaluations, forest management inventories, water resource estimates, coastal zone appraisals –Growth patterns of urban development, Spring run-off contaminants in lakes, land use in tropical rainforests, health of temperate conical forests, mapping wildfire hazards in Yosemite  Vegetation patterns –Annual cycle of vegetation dynamics, drought stress, and flooding –Dune reactivation in the US Great Plains, precision farming and land management  Glaciers and snow cover –Growth and retreat –Gradual changes in the Antarctic ice sheet  Geological surveys –Volcanic hazards and lava lakes

31. Geography 372 Fall 2003November 4, 2003 31 Chesapeake & Delaware Bays R=0.66 µm G=0.56 µm B=0.48 µm Baltimore Washington May 28, 1999

32. Geography 372 Fall 2003November 4, 2003 32 Benefits of Landsat 7 over other Missions  Mission Continuity –Spanning 25 years of multispectral imaging of the Earth’s surface, starting in 1972  Global Survey Mission –Approximately one quarter of the Earth’s landmass is imaged every 16 days »Every landmass will have seasonal coverage  Affordable Data Products –Landsat 7 data products are available from the EROS Data Center »Prices dropped from approximately $5,000 (Landsat’s 4 & 5) to $600 (Landsat 7) per scene

33. Geography 372 Fall 2003November 4, 2003 33 Washington, DC 1991 1999 Landsat 5 Infrared band Landsat 7 panchromatic band

34. Geography 372 Fall 2003November 4, 2003 34 Washington, DC Detail 1991 1999 Landsat 5 Infrared band Landsat 7 panchromatic band

35. Geography 372 Fall 2003November 4, 2003 35 Phoenix Development and Growth: 1973-1992 Multispectral Scanner (MSS)

36. Geography 372 Fall 2003November 4, 2003 36 San Francisco Bay from Landsat 7 R=0.66 µm G=0.56 µm B=0.48 µm Golden Gate Bridge Bay Bridge Oakland Airport

37. Geography 372 Fall 2003November 4, 2003 37 Cape Canaveral R=0.66 µm G=0.56 µm B=0.48 µm

38. Geography 372 Fall 2003November 4, 2003 38 Flood of the Mississippi River in 1993 Before the floods After the floods Landsat 5 TM

39. Geography 372 Fall 2003November 4, 2003 39 Flood of the Limpopo River in Mozambique  The Limpopo River in Mozambique before and after the flooding from Cyclone Eline  About 700 people were killed and thousands were displaced by this event August 22, 1999 March 2, 2000 Landsat 7 ETM+

40. Geography 372 Fall 2003November 4, 2003 40 Cape Town & the Western Cape

41. Geography 372 Fall 2003November 4, 2003 41 Landsat 7 Data Archived during First 400 Days of Operation

42. Geography 372 Fall 2003November 4, 2003 42 Bolivia from Landsat: 1984-1998 Thematic Mapper R=2.21 µm G=0.83 µm B=0.56 µm Colorado College Garden of the Gods Country Club