Introduction to Satellite Remote Sensing

Transcription

1 Introduction to Satellite Remote Sensing 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 first synoptic view of the Earth s weather systems. The manned Gemini and Apollo Programs ( ) led to further consideration of space-age remote sensing for study of the planet Earth. 1

2 Earth rising over the lunar surface, one of the most famous images of the 20th century. The photo was taken by astronaut William Anders from Apollo 8 in December 24, This is how Anders saw the image. Earth rising 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 RI 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.) 2

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. A significant feature of EREP was the use of man to operate the sensors in a laboratory fashion. The Earth Resources Technology Satellite (ERTS), later designated Landsat, provided repetitive multispectral observation of the Earth. 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. 3

4 Digital Data Acquisition Multispectral Digital Image Spatial Resolution (Pixel size) Spectral Resolution (Bands) 4

5 Landsat Missions Landsat 1 (07/12/ /06/1978) - RBV, MSS (80m) Landsat 2 (01/22/ /27/1983) - RBV, MSS (80m) Landsat 3 (03/05/ /07/1983) - RBV, MSS (80m) Landsat 4 (07/16/ ) - MSS, TM (30m, 120m TIR) Landsat 5 (03/01/ ) - MSS, TM (30m, 120m TIR) Landsat 6 (10/05/1993): ETM??? Landsat 7 (04/23/ ) - ETM+ (30m, 60m TIR, 15m Pan) Landsat 8 (February 11, 2013) OIL, TIRS (30m, 100m TIRS 15m Pan ) Landsat 9 (Scheduled lunch time: 2021) 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: m (blue) Provide increased penetration of water bodies, as well as supporting analysis of land use, soil, and vegetation characteristics. Band 2: 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: 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

6 Spectral Cover of Landsat Sensors (TM, ETM+) Band 4: m (Near-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: 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: m (Thermal infrared) This band measures the amount of infrared radiant flux emitted from surface. Band 7: 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 1-7 Sensors Multispectral Scanner (MSS) Landsat 1-5 Thematic Mapper (TM) Landsat 4 & 5 Enhanced Thematic Mapper Plus (ETM+) Landsat 7 Spectral Resolution ( m) (green) (red) (NIR) (NIR) (B) (G) (R) (NIR) (MIR) (TIR) (MIR) (Pan) Spatial Resolution (meter) 79 x x x 120 (TIR) 15 x 15 (Pan) 30 x x 60 (TIR) Temporal Resolution (revisit days) 18 (Landsat 1,2,3)

7 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

8 Landsat 8 Video Landsat-8 Sensors: Operational Land Imager (OLI) OLI spectral bands ETM + spectral bands # Band width GSD (m) # Band width GSD (m) (μm) (μm)

9 Landsat-8 Sensors: Operational Land Imager (OLI) 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 Spectral Resolution ( m) Multispectral Scanner (MSS) Landsat (green) (red) (NIR) (NIR) Comparison of Landsat Sensors Thematic Mapper (TM) Landsat 4 & (B) (G) (R) (NIR) (MIR) (TIR) (MIR) Enhanced Thematic Mapper Plus (ETM+) Landsat (Pan) Operational Land Imager (OLI) / Thermal Infrared Sensor (TIRS) Landsat (Pan) (TIRS) (TIRS) Spatial Resolution (meter) 79 x x x 120 (TIR) 15 x 15 (Pan) 30 x x 60 (TIR) 15 x 15 (Pan) 30 x x 100 (TIRS) Temporal Resolution (revisit days) 18 (Landsat 1,2,3) Example of Landsat 8 imagery (Fort Collins, Colorado, March 18, 2013) 10

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12 Rhode Island: Path 12/Row 31 12

13 Landsat Ground Stations Collections of Landsat Images of the World 13

14 Mangroves in the Niger River Delta: 1990 Landsat Image 14

15 Mangrove Forests On Landsat Images Over 100 km crisscrossing streams and rivers of the Kibasira Swamp 15

16 Streams and rivers eroding the banks of the Rufiji river Stiegler s Gorge section of the Rufiji River 16

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18 USGS EROS Data Center Monthly true color CONUS browse images, each pixel is shown generalized from m Landsat pixels to provide an approximate spatial resolution of 500 m. 18

19 QuickTime?and a decompressor are needed to see this picture. Web-enabled Landsat Data (WELD): Annual (December 2007 to November, 2008) Landsat ETM+ composited mosaics of the conterminous United States (Roy et al., 2010) Monthly Landsat composites, processed scenes Dec Jan Feb March 2010 April 2010 May 2010 June 2010 July 2010 August 2010 Sept Oct Nov

20 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 ( 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

21 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 nm. 21

22 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 NASA Operating Missions (as of 2011) 22

23 EOS AM Constellation / Ground Tracks National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project, or NPP, satellite was launched October 28, 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. 23

24 Global Precipitation Measurement (GPM) was launched February 27, GPM makes frequent (every 2 3 hours) observations of Earth s precipitation to improve the forecasting of extreme events and studying global climate. GPM builds on the notable successes of the Tropical Rainfall Measuring Mission (TRMM). Global Precipitation Measurement (GPM) Microwave Imager (GMI) serves an essential role in the nearglobal-coverage and frequentrevisit-time requirements of GPM. GPM passed over the northeastern U.S. on Oct. 29, 2017 at 8:36 p.m. EDT. The approximate location of the storm's center at the time of the GPM pass is shown with a large red "L". A large area of intense rain was located in the Atlantic east of the low's center. GMI estimated that rain in that area was falling at rates of greater than 2 inches (51 mm) per hour. The remnants of tropical storm Philippe on the five-year anniversary of Hurricane Sandy Credits: NASA/JAXA, Hal Pierce 24

25 NASA Planned and New Missions ( ) 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,

26 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. 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. 26

27 Sentinel Satellites (ESA) Initiate New Era n Earth Observation Sentinel Satellites (European Space Agency) Satellite Purpose Date Sentinel-1A Sentinel 1B Sentinel-2 Sentinel-3 Sentinel-5 Precursor Sentinel-4 Sentinel-5 Sentinel-6 Radar satellite that can see the Earth s surface in all weathers (two satellites to complete the RADAR pair) Multi-wavelength detectors to study principally land changes Similar to S2, but tuned to observe ocean properties and behavior The forerunner of Sentinel-5 to provide timely data on a multitude of trace gases and aerosols affecting air quality and climate. High-orbiting atmospheric sensor to give a global perspective on gases such as ozone Low-orbiting, high-resolution atmospheric sensor to help monitor air quality Future European name for the Jason sea-surface height mission with the US. It will carry a radar altimeter to provide high-precision and timely observations of the topography of the global ocean April 3, 2014 April 25, 2016 June, 2015 March 25, 2016 March 7, 2017 Scheduled 2021 Scheduled 2021 / 2022 Scheduled

28 Launched: September 24, 1999 Ground resolution: 1 meter panchromatic ( m), 4 meters multispectral (same as Landsat TM bands 1-4) (Band 1: m Blue) (Band 2: m Green) (Band 3: m Red) (Band 4: m Near IR) 28

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30 On October 19, 2001 DigitalGlobe launched the QuickBird 2 satellite. September 3, 2003 QuickBird Satellite Panchromatic Images (0.6-m Spatial Resolution) 30

31 September 3, 2003 QuickBird Satellite True-color and Pseudo-color Images 2.5-m Spatial Resolution Concept of Multispectral Or spectral resolution GeoEye-1, a Google sponsored satellite, launched 9/6/2008. Camera Modes Simultaneous panchromatic and multispectral (pansharpened) Panchromatic only Multispectral only Resolution 0.41 m / 1.34 ft* panchromatic 1.65 m / 5.41 ft* multispectral 31

32 WorldView-3 satellite imagery 30-cm Natural Color June 8, 2015 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) 32

33 SeaWiFS (Sea-Viewing Wide Field-of-View Sensor) was a satellite-borne sensor designed to collect global ocean biological data. Active from Sept to Dec. 2010, its primary mission was to quantify chlorophyll produced by arine phytoplankton (microscopic plants). SeaWiFS October 2001 SeaWiFS October 1997 Examples Of SeaWiFS Images 33

34 Landsat-1, 2, 3 Sensors and Sensing Society Over 1,000 satellites in space Over 10,000 air crafts (including UAVs) Over millions of ground based survey vehicles Over tens of millions of video sensors Over hundreds of millions of smart phones Artificial Intellengence? Landsat-4, 5 Landsat-7 Landsat-8 Satellites in Space? 34