Remote sensing

From Wikiversity
Jump to navigation Jump to search

Remote sensing (wiktionary | wikipedia | wikibooks)

NASA's Earth-observing fleet as of June 2012.
Infrared images of the region surrounding Gujarat, India, on January 21, 2001. Yellow-orange areas trace thermal anomalies that appeared days before the Jan. 26th earthquake. The boxed star denotes the quake's epicenter. Image was captured by MODIS onboard NASA's Terra satellite.- Source: NASA

The topic of Remote Sensing includes all earth-pointing satellites both past and presently operational. It can include aircraft remote sensing but in general that is generally not included because one cannot achieve global coverage as is possible with ease using satellites.

Overview[edit | edit source]

Remote Sensing refers to the ability to make observations remotely. Since the very first satellites were launched, their capability became obvious. Today remote sensing is a major enterprise and has become a vital part of weather forecasting, studying the climate and oceans and fields as diverse as oil exploration, geology, volcanology, sea-ice measurements, glaciers, agriculture, forestry and numerous other fields.

It holds an important role in helping track, study and understand global warming, and has been crucial in the detection of the ultimate extent of the ozone hole over the Antarctica and it's subsequent monitoring ever since.

Remote Sensing is an exciting multi-disciplinary subject that cuts across broads fields in science and technology and its applications and uses. It is now a vital element in humanity's ability to monitor the health and state of the Earth and will ultimately become an element when the collective decision is made to look after it properly.

The material presented here and still to be completed, should prove to be a good starting point to learn more, appreciate and understand this subject.

Learning Task[edit | edit source]

  • Explore different areas of peaceful application of remote sensing
    • Landslide detection by before and after comparison of the Digital Elevation Model (DEM)
    • Electricity Detection before and after comparison of light emission after Disasters,
  • How can remote sensing be used as Sustainable Development Goals indicators

Required Knowledge[edit | edit source]

It would be useful to have a basic knowledge of orbits and space, some basic physics, the solar spectrum.

Desirable[edit | edit source]

Knowledge of Blackbody radiation and it's characteristics. See Black_body (wiktionary | wikipedia | wikibooks)

Learning Material[edit | edit source]

Historical Overview[edit | edit source]

  • General historical overview
  • Technological development
  • Application development
  • Scientific progress
  • Timeline of key events

Basic Concepts[edit | edit source]

General Material[edit | edit source]

Operational Aspects[edit | edit source]

  • Ground stations -Discuss what they are, why they are needed, how many of them there are, and where they are sited.
  • Launches and orbital corrections
  • Onboard power and electronics -This is a topic in itself.
  • Data storage -this should give a brief history and then discuss volumes of data and locations and access
  • Communications and data transfer -give an overview of the way data is transferred and discuss the different transmission formats.

Data Processing[edit | edit source]

  • Techniques
  • Software programs
  • Calibration and Ground Truth Data
  • Satellite Data Archive Datasets -This should give a summary of the major sets data from current and previous satellites that is available for research, analysis and general study

Uses of Remote Sensing[edit | edit source]

Remote sensing is put to a wide range of uses and can be divided up into these broad categories below.

Agriculture[edit | edit source]

Weather Forecasting[edit | edit source]

  • Clouds, weather fronts, cyclones, hurricanes, wind speeds over the oceans, sea surface temperature, atmospheric moisture levels.

Aviation[edit | edit source]

  • Weather reports (e.g., forecasts of headwinds and storms)

Ecosystems[edit | edit source]

  • Mapping of ecosystems.

Mapping[edit | edit source]

  • The date from Landsat and SPOT are of main interest here.

Climatology[edit | edit source]

  • This section should discuss remote sensing of sea-ice, global cloudiness, Earth Radiation Budget, Ocean temperatures, biomass.

Satellite Classification[edit | edit source]

Satellites can be divided up into different types by orbit and also by type:

Satellites Classed by Orbit[edit | edit source]

Satellites Classed by Type[edit | edit source]

Remote Sensing Instrument Classifications[edit | edit source]

This covers the different types of instruments

Passive Instruments[edit | edit source]

  • Visible wavelengths
  • Infrared scanners
  • Microwave scanners
  • Gravational Effect -This actually has a different name.

Active Instruments[edit | edit source]

  • Radar
  • Lidar

Data Archives[edit | edit source]

This will list some of the archives available

US Satellites

  • Landsat data
  • NOAA
  • GOES
  • TOPEX and Jason (follow-on)
  • ERBS
  • TRMM Tropical Rainfall Measuring Mission
  • Nimbus
  • ERBS
  • SeaStart -(carries the SeaWIFS instrument)
  • Terra (formerly EOS AM-1) Atmospheric Science
  • CloudSat
  • Aqua
  • Others....

European (ESA) Satellites

  • Meteosat
  • SPOT
  • ERS-1, ERS-2
  • Envisat (Environmental Satellite)
  • Others....

Free Software and Data[edit | edit source]

See the NASA World_Wind software which is like Google Earth but has access to a large quantity of NASA satellite imagery including Landsat.

See World wind

See also[edit | edit source]

International Programmes[edit | edit source]

Glossary[edit | edit source]

Instrumentation[edit | edit source]

Lidar -This is basically a Laser radar

Orbital Terminology[edit | edit source]

Nadir -The point directly under a satellite




Related Areas[edit | edit source]