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Home , Remote sensing

Introduction to

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 (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 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.)

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 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, , and 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 , geology, forestry, regional planning, education and national security.

Landsat Video – Landsat Flyby https://www.youtube.com/embed/ZZx1xmNGcXI?list=PLD240BBC85537B9BE

4 Landsat-1, 2, 3 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 ??? (04/23/1999 - ) - ETM+ (30m, 60m TIR, 15m Pan) Landsat-4, 5 (February 11, 2013) – OIL, TIRS (30m, 100m TIRS 15m Pan )

ETM+: Enhanced Thematic Mapper Plus MSS: Multispectral Scanner

OLI: Operational Land Imager Landsat-7 Pan: Panchromatic RBV: Return Beam Vidicon Camera TIR: Thermal Infrared Landsat-8 TIRS: Thermal Infrared Sensor TM: Thematic Mapper

Spectral Cover of Band 1: 0.45-0.52m (blue). Landsat Sensors Provide increased penetration of water (TM, ETM+) bodies, as well as supporting analysis of land use, , 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 • Band 4: 0.76-0.90m (reflective infrared). This band is responsive to the Spectral Cover of amount of vegetation biomass present in Landsat Sensors the scene. It is useful for crop (TM, ETM+) 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.

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

6 Landsat-8 and Sensors:

Landsat-8 Sensors: Operational Land Imager (OLI) OLI spectral bands ETM + spectral bands # Band width GSD (m) # Band width GSD (m) (μm) (μm) 1 0.43–0.45 30 2 0.45–0.51 30 1 0.45–0.52 30 3 0.53–0.59 30 2 0.52–0.60 30 4 0.64–0.67 30 3 0.63–0.69 30 5 0.85–0.88 30 4 0.77–0.90 30 6 1.57–1.65 30 5 1.55–1.75 30 7 2.11–2.29 30 7 2.09–2.35 30 8 0.50–0.68 15 8 0.52–0.90 15 9 1.36–1.38 30

7 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 10.60-11.19 100 11 11.50-12.51 100

8 Multispectral Scanner Thematic Mapper Enhanced Thematic Operational Land Imager (MSS) (TM) Landsat 4 & 5 Mapper Plus (ETM+) (OLI) Landsat 8 Landsat 1-5 Landsat 7

• 0.5-0.6 (green) 1. 0.45-0.52 (B) 1. 0.45-0.52 (B) 1. 0.43-0.45 (Ultra-B) • 0.6-0.7 (red) 2. 0.52-0.60 (G) 2. 0.52-0.60 (G) 2. 0.45-0.51 (B) • 0.7-0.8 (NIR) 3. 0.63-0.69 (R) 3. 0.63-0.69 (R) 3. 0.53-0.59 (G) • 0.8-1.1 (NIR) 4. 0.76-0.90 (NIR) 4. 0.77-0.90 (NIR) 4. 0.64-0.67 (R) Spectral 5. 1.55-1.75 (MIR) 5. 1.55-1.75 (MIR) 5. 0.85-0.88 (NIR) Resolution 6. 10.4-12.5 (TIR) 6. 10.4-12.5 (TIR) 6. 1.57-1.65 (MIR) (m) 7. 2.08-2.35 (MIR) 7. 2.09-2.35 (MIR) 7. 2.11-2.29 (MIR) 8. 0.52-0.90 (Pan) 8. 0.50-0.68 (Pan) 9. 1.36-1.38 (MIR) 10. 10.60-11.19 (TIRS) 11. 11.50-12.51 (TIRS)

Spatial 30 x 30 15 x 15 (Pan) 15 x 15 (Pan) Resolution 79 x 79 120 x 120 (TIR) 30 x 30 30 x 30 (meter) 60 x 60 (TIR) 100 x 100 (TIRS)

Temporal Resolution 18 (Landsat 1,2,3) 16 16 16 (revisit days)

Example of Landsat 8 imagery (Fort Collins, Colorado, March 18, 2013)

9 Landsat 8 Video https://www.youtube.com/watch?v=mqVKR9OnqqA

10 Landsat Ground Stations

Collections of Landsat Images of the World

11 12 Rhode Island: Path 12/Row 31

13 Mangroves in the Niger River Delta: 1990 Landsat Image

Mangrove Forests On Landsat Images

14 Streams and rivers eroding the banks of the Rufiji river

Stiegler’s Gorge section of the Rufiji River

15 16 USGS EROS Data Center http://earthexplorer.usgs.gov/

USGS EROS Data Center http://earthexplorer.usgs.gov/

17 (EOS AM) - Launched December 18, 1999 The following instruments fly on TERRA:

ASTER: Advanced Spaceborne Thermal Emission and Reflection Radiometer (15m - 3 bands in VNIR; 30m - 6 bands in SWIR; 90m - 5 bands in TIR)

MODIS: 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 Spectroradiometer MOPITT: Measurements of Pollution in the Troposphere.

Provisional Land Cover Product June 01

MODIS data from Jul 00– Jan 01

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18 The MODIS Global Vegetation 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 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 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 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.

Shuttle Mission (SRTM), February 11-22, 2000, obtained the high-resolution digital topographic database of the Earth (DEM) in GIS Mt. Kilimanjaro (5,895 m)

Tanzania/ Kenya Coastal Zone

21 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

22 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.

23 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.

ESA Sentinel-1 is a two satellite constellation with the prime objectives of Land and monitoring. The goal of the mission is to provide C-Band SAR data continuity following the retirement of ERS-2 and the end of the mission.

•Launch Dates: •Sentinel-1A - 03 April 2014; Sentinel-1B - 25 April 2016

Mission Objectives: •Land monitoring of forests, water, soil and agriculture •Emergency mapping support in the event of natural disasters •Marine monitoring of the maritime environment • ice observations and iceberg monitoring •Production of high resolution ice charts •Forecasting ice conditions at sea •Mapping oil spills •Sea vessel detection • monitoring

24 ESA Sentinel-2 mission is a land monitoring constellation of two satellites that provide high resolution optical imagery and provide continuity for the current SPOT and Landsat missions. The first Sentinel-2 satellite was launched on 23 June 2015.

The mission provides a global coverage of the Earth's land surface every 10 days with one satellite and 5 days with 2 satellites, making the data of great use in on-going studies.

The satellites are equipped with the state-of-the-art MSI (Multispectral Imager) instrument, that offers high- resolution optical imagery.

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)

25 26 On October 19, 2001 DigitalGlobe launched the QuickBird 2 satellite.

27 September 3, 2003 QuickBird Satellite True-color and Pseudo-color Images 2.5-m Spatial Resolution

Concept of Multispectral Or spectral resolution

Natural color, high-resolution DigitalGlobe satellite image featuring the Golden Gate Bridge and Toll Plaza.

Image collected March 7, 2010

28 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

WorldView-3, launched into orbit on August 13, 2014, is now the world’s most technologically advanced high-resolution satellite.

WorldView-3 collects • 31-centimeter (cm) panchromatic, • 1.24-meter (m) multispectral, • 3.7-m shortwave infrared (SWIR) and • 30-m CAVIS (Cloud, , Vapor, Ice, ) imagery.

At a maximum 31-cm resolution, this imagery will rival the clarity of 20 to 25-cm aerial data given its superior optical and production systems.

29 Satellites in Space?

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