GIS Day 2015
Geospatial Technologies
• GPS (global positioning system)
– Car GPS systems, yield monitors, smart phones
• RS (remote sensing)
– Satellite or Aircraft imagery (Including UAS)
– Your camera
• GIS (geographic information system)
–
–
–
–
Combines layers of information
Can include GPS and RS information
Provides analytic tools
ArcGIS, ArcGIS Online, QGIS, GoogleEarth?
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October 8, 2015
What Is Remote Sensing (RS)
Remote sensing is the science of obtaining
information about objects or areas from a distance,
typically from aircraft or satellites.
- oceanservice.noaa.gov/facts/remotesensing.html
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October 8, 2015
RS Measures Spatial Variations
30 meter or 100 foot pixels
October 8, 2015
0.3 meter or 1 foot pixels
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RS Measures Spectral Variations
Natural Color
October 8, 2015
Color Infrared Red
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The Electromagnetic Spectrum
Landsat 8 spectral range
Infrared does not always mean thermal or heat!!!
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October 8, 2015
Reflectance Curves for Some Features
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2
4
3
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Landsat 8
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7
8
5
3
2
4
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October 8, 2015
RS Measures Temporal Variations
Landsat 5 – July 17, 1986
October 8, 2015
Landsat 8 – May 24, 2013
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Why Does the “Turf” Appear Different for
Football and Baseball Fields In Color IR?
Natural Color
October 8, 2015
Color Infrared Red
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Comparison of Spectral Responses
Response from Grass Area
• Notice the difference in
channel 4 or the near
infrared band
Response from Football Field
• Use of near infrared
was very helpful for
camouflage detection
during World War II
• Any thoughts on how
else these type of
response differences
can be used?
Channel numbers in order of blue, green, red, near infrared red
October 8, 2015
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Measure Distance by Pixels
Distance between lines
Pixel
Lines 3280 to 3294
Each pixel is 1 foot on a side
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October 8, 2015
Useful Web Site Links
• Freeware Application to View Remote Sensing Data
• MultiSpec: Available for Macintosh & Windows platforms
•
engineering.purdue.edu/~biehl/MultiSpec/
• Web-enabled: mygeohub.org/tools/multispec
(will need to register)
• Source for Image Data
• IndianaMap: maps.indiana.edu/
• County Landsat Images:
•
www.indianaview.org/glovis/IN_County_Landsat_Data.html
• Aerial high spatial resolution images:
•
gis.iu.edu/isdp_dl/map/m10000.html
• Geography Educators’ Network of Indiana (GENI):
•
www.iupui.edu/~geni/
• AmericaView Earth Observation Day: Oct. 14, 2015
•
www.americaview.org/earth-observation-day
October 8, 2015
Contact: Larry Biehl - biehl@purdue.edu
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Is Remote Sensing a Science?
or an Art?
From Landsat 7 scene over Garden City, Kansas; 9/1/2000
October 8, 2015
eros.usgs.gov/imagegallery/earth-art
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