Introduction to Satellite Remote Sensing 1
Remote sensing of the Earth from orbital altitudes was recognized in the mid-1960 s as a potential technique for obtaining information important for the effective use and conservation of natural resources. The studies began when the Tiros satellites (1960) provided man s first synoptic view of the Earth s weather systems. The manned Gemini and Apollo Programs (1962-1972) led to further consideration of space-age remote sensing for study of the planet Earth. The Earth Resources Technology Satellite (ERTS), later designated Landsat, provided repetitive multispectral observation of the Earth. 2
Earth Rising The photo was taken by astronaut William Anders from Apollo 8 in December 24, 1968. As Apollo 8 raced backward away from the Earth, Anders snapped a picture of a fist-sized fuzzy little ball of color against the immense backdrop of space. (Parker, RI News, Providence Journal, Oct. 24, 2010) (Anders lived in Barrington for about 5 years in 1980s as an executive at RI-based Textron. He was inducted Into Rhode Island Aviation Hall of Fame for his role on Apollo 8.) Earth rising over the lunar surface, one of the most famous images of the 20th century. This is how Anders saw the image. NASA 3
Skylab, the largest manned space station placed at low Earth orbit at the time, was lunched in May 14, 1973 and carried into space the Earth Resources Experiment Package (EREP). EREP was designed to view the Earth with sensors that recorded data in visible, infrared, and microwave spectral regions. EREP became another step in space exploration by testing the high spatial resolution camera systems with film return capability, narrow frequency bandwidth scanner systems in the visible through thermal-infrared spectral region, and initial use of active and passive microwave systems in Earth resources surveys. A significant feature of EREP was the use of man to operate the sensors in a laboratory fashion. Landsat represents the world's longest (since 1972) continuously acquired collection of space-based land remote sensing data. The instruments on the Landsat satellites have acquired millions of images. The images, archived in the United States and at Landsat receiving stations around the world, are a unique resource for global change research and applications in agriculture, geology, forestry, regional planning, education and national security. 4
Landsat Missions Landsat 1 (07/12/1972-01/06/1978) - RBV, MSS (80m) Landsat 2 (01/22/1975-07/27/1983) - RBV, MSS (80m) Landsat 3 (03/05/1978-09/07/1983) - RBV, MSS (80m) Landsat 4 (07/16/1982 - ) - MSS, TM (30m, 120m TIR) Landsat 5 (03/01/1984 - ) - MSS, TM (30m, 120m TIR) Landsat 6 (10/05/1993): ETM??? Landsat 7 (04/23/1999 - ) - ETM+ (30m, 60m TIR, 15m Pan) Landsat 8 (February 11, 2013) OIL, TIRS (30m, 100m TIRS 15m Pan ) Landsat-4, 5 Landsat-1, 2, 3 ETM+: Enhanced Thematic Mapper Plus MSS: Multispectral Scanner OLI: Operational Land Imager Pan: Panchromatic RBV: Return Beam Vidicon Camera TIR: Thermal Infrared TIRS: Thermal Infrared Sensor TM: Thematic Mapper Landsat-8 Landsat-7 Spectral Cover of Landsat Sensors (TM, ETM+) Band 1: 0.45-0.52 m (blue). Provide increased penetration of water bodies, as well as supporting analysis of land use, soil, and vegetation characteristics. Band 2: 0.52-0.60 m (green). This band spans the region between the blue and red chlorophyll absorption bands and therefore corresponds to the green reflectance of healthy vegetation. Band 3: 0.63-0.69 m (red). This is the red chlorophyll absorption band of healthy green vegetation and represents one of the most important bands for vegetation discrimination. 5
Spectral Cover of Landsat Sensors (TM, ETM+) Band 4: 0.76-0.90 m (reflective infrared). This band is responsive to the amount of vegetation biomass present in the scene. It is useful for crop identification and emphasizes soil-crop and land-water contrasts. Band 5: 1.55-1.75 m (mid-infrared) This band is sensitive to the amount of moisture in plants and therefore useful in crop draught and in plant vigor studies. Band 6: 10.4-12.5 m (thermal infrared) This band measures the amount of infrared radiant flux emitted from surface. Band 7: 2.08-2.35 m (mid-infrared) This is an important band for the discrimination of geologic rock formation. It is effective in identifying zones of hydrothermal alteration in rocks. Comparison of Landsat Sensors Spectral Resolution ( m) Spatial Resolution (meter) Temporal Resolution (revisit in days) Spatial coverage (km) Thematic Mapper (TM) Landsat 4 and 5 1. 0.45-0.52 (B) 2. 0.52-0.60 (G) 3. 0.63-0.69 (R) 4. 0.76-0.90 (NIR) 5. 1.55-1.75 (MIR) 7. 2.08-2.35 (MIR) 6. 10.4-12.5 (TIR) 30 x 30 120 x 120 (TIR) Enhanced Thematic Mapper Plus (ETM+) Landsat 7 1. 0.45-0.52 2. 0.53-0.61 3. 0.63-0.69 4. 0.78-0.90 5. 1.55-1.75 7. 2.09-2.35 6. 10.4-12.5 8. 0.52-0.90 (Pan) 15 x 15 (Pan) 30 x 30 60 x 60 (TIR) Multispectral Scanner (MSS) Landsat 1-5 0.5-0.6 (green) 0.6-0.7 (red) 0.7-0.8 (NIR) 0.8-1.1 (NIR) 79 x 79 16 16 18 (Landsat 1,2,3) 185 x 185 183 x 170 185 x 185 Altitude (km) 705 705 915 (Landsat 1,2,3) 6
Landsat-7 ETM+ Data of Providence Landsat-7 Panchromatic Data (15 m) Landsat-7 ETM+ Data (30 m), Bands 3, 2, 1 in RGB Landsat-7 ETM+ Data (30 m), Bands 4, 3, 2 in RGB Landsat-7 ETM+ Data (30 m), Bands 4, 5, 3 in RGB Landsat-8 and Sensors: 7
Landsat-8 Sensors: Operational Land Imager (OLI) OLI spectral bands ETM + spectral bands # Band width GSD (m) # Band width GSD (m) (μm) (μm) 1 0.433 0.453 30 2 0.450 0.515 30 1 0.450 0.515 30 3 0.525 0.600 30 2 0.525 0.605 30 4 0.630 0.680 30 3 0.630 0.690 30 5 0.845 0.885 30 4 0.775 0.900 30 6 1.560 1.660 30 5 1.550 1.750 30 7 2.100 2.300 30 7 2.090 2.350 30 8 0.500 0.680 15 8 0.520 0.900 15 9 1.360 1.390 30 Landsat-8 Sensors: Operational Land Imager (OLI) 8
Landsat-8 Sensors: Thermal Infrared Sensor (TIRS) TIRS Sensors measure land surface temperature in two thermal bands. Band # Center wavelength (μm) Spatial resolution (m) 10 10.6-11.2 100 11 11.5-12.5 100 Example of Landsat 8 imagery (Fort Collins, Colorado, March 18, 2-13) 9
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Rhode Island: Path 12/Row 31 11
Landsat Ground Stations Collections of Landsat Images of the World 12
Mangroves in the Niger River Delta: 1990 Landsat Image 13
Mangrove Forests On Landsat Images Over 100 kilometers crisscrossing streams and rivers of the Kibasira Swamp 14
Streams and rivers eroding the banks of the Rufiji river Stiegler s Gorge section of the Rufiji River 15
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USGS EROS Data Center http://edcsns17.cr.usgs.gov/earthexplorer/ USGS EROS Data Center http://eros.usgs.gov/#/remote_sensing 17
TERRA (EOS AM) - Launched December 18, 1999 The following instruments fly on TERRA: ASTER: MODIS: Advanced Spaceborne Thermal Emission and Reflection Radiometer (15m - 3 bands in VNIR; 30m - 6 bands in SWIR; 90m - 5 bands in TIR) Moderate Resolution Spectroradiometer (0.4-14.4 m) (250m - 2 bands, 500m - 5 bands, 1000m - 29 bands) CERES: Clouds and the Earth's Radiant Energy System MISR: Multi-angle Imaging Spectroradiometer MOPITT: Measurements of Pollution in the Troposphere. Provisional Land Cover Product June 01 MODIS data from Jul 00 Jan 01 36 18
The MODIS Global Vegetation Phenology product (MOD12Q2) provides estimates of the timing of vegetation phenology at global scales. As such, MOD12Q2 identifies the vegetation growth, maturity, and senescence marking seasonal cycles. EO-1: successfully launched on November 21, 2000 ALI - Advanced Land Imager consists of a 15 Wide Field Telescope (WFT) and partially populated focal plane occupying 1/5th of the field-of-view, giving a ground swath width of 37 km. Hyperion Hyper-spectral sensors a grating imaging spectrometer having a 30 meter ground sample distance over a 7.5 kilometer swath and providing 10nm (sampling interval) contiguous bands of the solar reflected spectrum from 400-2500nm. 19
Hyperspectral data Hyperion sensor on board the EO-1 Satellite Spectral profile in a single pixel location from 0.4 to 2.5 m at 10 nm interval for a continuous coverage over 220 bands EO-1 launched November 21, 2000 EOS AM Constellation / Ground Tracks 20
SPOT satellites SPOT 5 was successfully launched on May 3, 2002 SPOT 4 - March 24, 1998 SPOT-4 VEGETATION SPOT 3 - Sept. 25, 1993 SPOT 2 - Jan. 22, 1990 SPOT 1 - Feb. 21, 1986 The SPOT Sensor The position of each HRV entrance mirror can be commanded by ground control to observe a region of interest not necessarily vertically beneath the satellite. Thus, each HRV offers an oblique viewing capability, the viewing angle being adjustable through +/- 27degrees relative to the vertical. Two spectral modes of acquisition are employed, panchromatic (P) and multispectral (XS). Both HRVs can operate in either mode, either simultaneously or individually. 21
SPOT 4-VEGETATION: This program marks a significant advance to monitor crops and the continental biosphere. The VEGETATION instrument flying on Spot 4 provides global coverage on an almost daily basis at a resolution of 1 kilometer, thus making it an ideal tool for observing long-term environmental changes on a regional and worldwide scale. With a swath width of 2,250 kilometers, the VEGETATION instrument covers almost all of the globe's land masses while orbiting the Earth 14 times a day. Only a few zones near the equator are covered every day. Areas above 35 latitude are seen at least once daily. Launched: September 24, 1999 Ground resolution: 1 meter panchromatic (0.45-0.90 m), 4 meters multispectral (same as Landsat TM bands 1-4) (Band 1: 0.45-0.52 m Blue) (Band 2: 0.52-0.60 m Green) (Band 3: 0.63-0.69 m Red) (Band 4: 0.76-0.90 m Near IR) 22
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On October 19, 2001 DigitalGlobe launched the QuickBird 2 satellite. 24
September 3, 2003 QuickBird Satellite Panchromatic Images (0.6-m Spatial Resolution) September 3, 2003 QuickBird Satellite True-color and Pseudo-color Images 2.5-m Spatial Resolution Concept of Multispectral Or spectral resolution 25
Natural color, high-resolution DigitalGlobe satellite image featuring the Golden Gate Bridge and Toll Plaza. Image collected March 7, 2010 GeoEye-1, a Google sponsored satellite, was launched September 6, 2008. Camera Modes Simultaneous panchromatic and multispectral (pan-sharpened) Panchromatic only Multispectral only Resolution 0.41 m / 1.34 ft* panchromatic 1.65 m / 5.41 ft* multispectral 26
GeoEye's next satellite, GeoEye-2, is in a phased development process for an advanced, third-generation satellite capable of discerning objects on the Earth s surface as small as 0.25-meter (9.75 inch) in size, due to launch in 2013. Shuttle Radar Topography Mission (SRTM), February 11-22, 2000, obtained the high-resolution digital topographic database of the Earth Mt. Kilimanjaro (5,895 m) Digital Elevation Model (DEM) in GIS Tanzania/ Kenya Coastal Zone 27
SeaWiFS October 2001 SeaWiFS October 1997 Credit line for all images: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE Examples Of SeaWiFS Images 28
October 28, 2011 National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project, or NPP, satellite was launched successfully. This marks the start of the next generation of space-based weather and climate observations. NPP becomes one of NASA s newest eye in the sky to keep tabs on the ozone, improve hurricane science, and maintain steady records of the changing climate - and will fill the void if any of the current polar satellites should fail. Satellites in Space? 29