4. What is Remote Sensing?
Remote sensing is a method of obtaining
information about the properties of an object
without coming into physical contact with it.
5. Remote Sensing is a technology for sampling
electromagnetic radiation to acquire and interpret
non-immediate geospatial data from which to extract
information about features and objects on the Earth's
land surface, oceans, and atmosphere
- Dr. Nicholas Short
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6. Remote Sensing
RS System capture radiation in different
wavelength reflected/ emitted by the earth’s
surface features and recorded it either directly
on the film as in case of aerial photography or
in digital medium used for generating the
images
RS provides valuable data over vast area in a
short time about resources, meteorology and
environment leading to better resource
management and accelerating national
development
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7. Advantages of remote sensing
Provides a regional view (large areas)
Provides repetitive looks at the same area
Remote sensors "see" over a broader portion
of the spectrum than the human eye
Sensors can focus in on a very specific
bandwidth in an image or a number of
bandwidths simultaneously
Provides geo-referenced, digital, data
Some remote sensors operate in all seasons,
at night, and in bad weather
9. Elements involved in Remote
sensing
1. Energy Source or Illumination (A)
2. Radiation and the Atmosphere (B)
3. Interaction with the Object (C)
4. Recording of Energy by the Sensor (D)
5. Transmission, Reception and
Processing (E)
6. Interpretation and Analysis (F)
7. Application (G)
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12. Why use Satellites to Study the
Earth?
Consistent, routine, global measurements
Overview of information on the hemispheric,
regional, national, and local scales – the “big
picture”
Provide information in areas where there are no
ground-based measurements
Advance warning of impending environmental
events and disasters
Visual appeal: a picture is worth
a thousand words
13. Satellites Provide a Global View
Satellite data are used for many applications, including
monitoring global weather, studying climate change, and
observing the environment.
14. A Picture is Worth a Thousand Words!
Satellites provide consistent, routine, global coverage of
environmental events
15. Satellite Images
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•
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•
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Advantages
Covers large areas
Cost effective
Time efficient
Multi-temporal
Multi-sensor
Multi-spectral
Overcomes inaccessibility
Faster extraction of GISready data
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Disadvantages
Needs ground verification
Doesn’t offer details
Not the best tool for small areas
Needs expert system to extract
data
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25. Remote sensing basic processes
Data acquisition (energy propagation, platforms)
Processing (conversion of energy pattern to
images)
Analysis (quantitative and qualitative analysis)
Accuracy assessment (radiometric and
geometric correction)
Information distribution to users (hard copy,
CCT, CD-ROM, X-BYTE)
27. Geostationary Satellites
• In high altitude orbit (~35,800 km)
• Orbital period of satellite matches
rotational speed of Earth
• Continuously observe same area
on Earth
• Very high temporal resolution
(minutes – hours)
• Usually used to monitor
meteorological conditions and
severe storm development,
including hurricanes, tornadoes,
and floods
28. Polar-Orbiting Satellites
• In low altitude orbit (~700-800 km)
• Orbit around North and South Poles
• Earth rotates under satellite as it orbits, so
each time satellite makes a pass over Earth,
it observes a new area
• Polar-orbiting satellites observe same area
on Earth once per day (or less)
• Low temporal resolution
• Global coverage!
• Used for a variety of applications, including
air quality, land cover, water quality, and
vegetation studies
29. How Do Satellites Make
Measurements?
Satellites do not make direct
measurements of the Earth’s
geophysical parameters.
Instead, satellites measure solar
and/or terrestrial radiance (light)
in a vertical column of the
atmosphere.
Radiance data are converted into
geophysical parameters using
science-based algorithms.
30. Remote Sensing : Challenges
Satellites are very expensive to build and launch.
No direct measurements – radiance (light)
measurements must be converted to geophysical
parameters, such as temperature or pollutant
concentration.
Tradeoffs between spatial and temporal
resolution.
32. Conclusion
Radars, Laser Range finders, UAV
based Reconnaissance and
Satellite Imagery are widely used in
Defense forces
Advantages of Remote Sensing far
outweigh the challenges
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34. History of remote sensing
1783: The Marquis d’Arlandes and Pilatre made a voyage near Paris using a balloon.
Photography using balloon, pigeon
1860: Aerial photos in Russia and the USA
1914-19: The first World War and the second World War (1939-45) had seen
tremendous development in photography
1927: Robert Goddard launched the first liquid-fueled rocket.
1955: Work began on the Baikonur launch site in central Asia.
1957: Sputnik 1 launched from Baikonur (first satellite)
1961: Yuri Gagarin launched in the Vostok 1 capsule, becoming the first human in
space.
1969: Neil Armstrong and Buzz Aldrin became the first humans to walk on the Moon.
1971: The first Space Station in history, the Russian Salyut 1
1972: (US Landsat1) the concept of imaging from satellites is introduced
1986: France launched the first stereo-image satellite (SPOT1)
1992: The space year (the maturity of remote sensing - 20 years of operation)
1995 The Shuttle-Mir Program (1st phase of the International Space Station (ISS).
2000 The first 3 astronauts (2 Russian and one American) start to live in the
ISS
35. Remote Sensing Organizations
ISPRS- International Society for Photogrammetry and Remote
Sensing
IGARSS- International Geosciences And Remote Sensing
Symposium
NASA -National Aeronautic and Space Administration (USA)
ESA- European Space Agency (Europe)
NASDA- National Space Development Agency (Japan)
CNES- Centre National d'Etudes Spatiales (France )
DARA- German Space Agency
CSA - Canadian Space Agency
NRSA- National Remote Sensing Agency of India
36. Remote sensing web sites
http://ftp.geog.ucl.ac.be/~patrick/geogr/Eteledetec.html - remote sensing
index
http:// www.esrin.esa.it - Eurpopean Space Agency
http://geo.arc.nasa.gov - NASA program http://www.spot.com
http://www.nasda.go.jp/ - Japan space agency
http://www.rka.ru./ Russian Space Agency (RSA)
http://www.coresw.com - Russian imagery source
http://www.space.gc.ca/ Canadian Space Agency (CSA)
http://www.ccrs.nrcan.gc.ca/ccrs/ -Canada Center for Remote Sensing
http://www.inpe.br/ National Institute for Space Research (Brazil)
http://www.asprs.org
- American Society
http://www.man.ac.uk
- Manshester Univ.
http://www.idrisi.clarku.edu - Idrisi site
http://www.amazon.com
- Bookstore
http://www.brevard.cc.fl.us/BTR_Labs/bober/martin/rs/overview.htm
Dr. Martin McClinton,
37. Remote sensing literatureJ ournal/Conferences
Photogrammetric Engineering and
Remote sensing (PE & RS)
Photogrammetric Record
International Journal of Remote Sensing
ISPRS Journal of Photogrammetry and
Remote Sensing
ISPRS conference proceedings
IGARSS conference proceedings
38. Remote sensing literature -B ooks
Askne, J. (1995). Sensors and Environmental applications of
remote sensing, Balkema, Rotterdam, NL
Campbell, J. B. , 1996. Introduction to Remote Sensing. 2nd
ed.,Taylor and Francis, London
Dengre, J. (1994). Thematic Mapping from satellite imagery: Guide
book, Elsevier ltd, Boulevard
Lillesand, T. M. and R. W. Kiefer, 2000. Remote Sensing and Image
Interpretation. 4th ed., John Wiley and Sons, Inc. New York
Simonette, D. S. (ed) (1983) Manual of remote sensing, the
Sheridan Press, Falls church
Lillesand Thomas M. & Kiefer Ralph 2003 : Remote Sensing and
Image Interpretation Third Edition John Villey
Campbell John B. 1996 : Introduction to Remote Sensing, Taylor &
Francis
Floyd F. Sabins : Remote Sensing and Principles and Image
Interpretation(1987)
Manual of Remote Sensing IIIrd Edition : American Society of
Photogrammtery and Remote Sensing 210, Little Falls Street, Falls
Church, Virginia-22046 USA
George Joseph. 1996: Imaging Sensors ; Remote Sensing Reviews,
vol 13,Number 3-4.
P.J. Curran, 1985. Physical aspects of Remote Sensing Longman
Group UR Ltd, England.
