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OutlineWhat is remote sensing?How does remote sensing work?
What role does the electromagnetic spectrum play in satellite imagery?
How can satellite imagery be applied in science classrooms?
Common Vocabulary Remote sensing- gathering data without direct
contact. Satellite- in this case, a man-made machine
orbiting the Earth that collects reflected radiation from the Earth’s surface.
Pixel-picture element or the size of the digital block of information
Resolution- the “clarity” or amount of data stored in a pixel. Resolution relates to pixel size. The smaller the pixel the greater the resolution.
Identifying, observing, and measuring an object without coming into direct contact with it (NASA)
What is remote sensing?
So many satellites and sensors
According to NASA-there were about 3000 satellites operating in Earth orbit in 2012.
US Satellite Orbits
Constellation
Satellite imagery is a special case of digital photography.
Radiation bands in the electromagnetic spectrum that are reflected from the Earth’s surface back into space can be collected by satellite sensors and stored digitally as pixels.
The most common electromagnetic bands for satellite imagery are visible light, near infrared radiation (NIR), and infrared radiation (IR).
How does Remote Sensing work?
http://marine.rutgers.edu/mrs/education/class/yuri/erb.html
Some satellites collect only the radiation that that is reflected from the surface of the earth. (Passive)
Other satellites like JASON, emit radiation at 13.6 GHz and 5.3GHz and measure the time it takes for the “round trip”. (Active)
Active satellites measure elevation and are used to generate topography.
What role does the Electromagnetic Spectrum play in RS?
Reflectance
http://accessscience.com/search.aspx?rootID=796762
EES Sensor RangesVisible Spectrum- full color digital photographyInfrared- “heat”
Near-Infrared- vegetationMid-Infrared- soils
Ultraviolet- clouds and snow cover
All color images require “processing”.
Differences Among Infrared RegionsNear IR- (0.7 - 1)microns
740 K- (3000-5200 K) Earth’s surface and above
Mid IR 5 to (25-40) microns (92.5-140) K to 740 K only above the atmosphere
Far IR (25-40) to (200-350) microns (10.6-18.5) K to (92.5-140) K only above the atmosphere
Reminder : C° + 273 = K
Visible and Near IR ComparisonsA B
A B
Examples of Satellite ImageryNASA and Google Earth
How can scientists use IR data to study the earth’s surface?
Kohrs, Infrared Image
Landsat Program
Temporal: 16 days
Spectral: 4-8 bands
Spatial resolution: 30 m
http://earthobservatory.nasa.gov/Features/Landsat/
Land cover and land cover change
MODIS (Moderate Resolution Imaging Spectroradiometer)
Temporal: DailySpectral: 36 bandsSpatial: 250-1000 m http://modis.gsfc.nasa.gov/about
Global land cover and ocean RS
Fire monitoring
IKONOS- commercial
Temporal: On DemandSpectral: 4 bands, panchromaticSpatial: 1-4 mLocal land cover http://www.satimagingcorp.com/
gallery-ikonos.html
JASON (Active)Temporal: 10 daysSpectral: NA (Active)Spatial: ~ 2 km http://ilrs.gsfc.nasa.gov/satellite_missions/
list_of_satellites/jas2_general.html
Sea level
How can satellite imagery be applied to
EES classrooms? Weather forecasting
Storm tracking Ocean temperature monitoring Sea level changes Large scale land
mass & land use changes
Resources NC OneMap-data and imagery
http://www.nconemap.com/
National Map-data and imagery http://nationalmap.gov/viewer.html
Imagery Sources http://www.info.com/nasa%20satellite%20imagery?cb
=27&cmp=3913&gclid=CP20qKO6xrACFYlk7Aodw0_QoA
http://weather.msfc.nasa.gov/GOES/ http://www.goes.noaa.gov/ http://
en.wikipedia.org/wiki/File:EM_Spectrum_Properties_edit.svg
NASA and NOAA http://eospso.gsfc.nasa.gov/
SummaryRemote sensing allows us to
observe and monitor the earth surface.
Features on the Earth’s surface can be interpreted using spectral/electromagnetic information.
Satellites have a wide range of purposes.
