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Ann Arbor, MI Thermal Imagery
Image : ann-arbor_daedalus_1981-05-09_06-30-am.img Sensor : Daedalus DS-1230 Quantitative Thermal Infrared Scanning System IFOV : 1.0 milliradian Detector : Mercury Cadium Telluride (Hg-Cd-Te) operating in the 8 - 14 micrometer region Acquired : May 9, 1981 Altitude : 3600 meters above ground level (AGL) Time over Target : 6:30 am Air Temp at Ground Level : 19 degrees C |
2. What would be the smallest dimension (in meters) of features you will be able to resolve on the ground?
3. Notice that the roads and river image in lighter tone than the vegetated areas. Explain why this phenomenon occurs.
4. What are the extremely dark, "block" areas in downtown Ann Arbor?
5. Do you see evidence of a thermal gradient as you progress from the Central Business District (CBD) out into the countryside? Explain why this phenomenon exists, and why it is amenable to being sensed in the 8 - 14 micrometer region.
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Residential Area Fort Worth, TX Thermal Imagery
Image : fort-worth_daedalus_1980-01-10_06-45-am.img Sensor : Daedalus DS-1230 Quantitative Thermal Infrared Scanning System IFOV : 1.0 milliradian Detector : Mercury Cadium Telluride (Hg-Cd-Te) operating in the region 8 - 14 micrometers Acquired : January 10, 1980 Altitude : 250 meters above ground level (AGL) Time over Target : 6:45 am Air Temp at Ground Level : 12 degrees C |
7. Provide a brief description of why the following features appear as they do in this thermal infrared image:
Roads
Natural and man-made vegetation
Sidewalks and patios
Storage sheds in back yards
Automobiles
Bright spots on many of the roof tops
8. Explain why the front parts of the cars have a hot spot on them at arrows number 1 and 2.
9. Explain the reason some yards are darker that others, and why many backyards are brighter than front yards.
10. Note the heat loss in the roof at the house located at arrow number 3. Describe the variables you would demand to know if you owned the house and a salesperson was trying to convince you that you needed insulation based on an analysis of this image.
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USC Thermal Imagery
Image : columbia_1983-03-10.img IFOV : 2.5 milliradians Acquired : March 10,1983 Altitude : 500 meters above ground level (AGL) |
Thermal imagery has many uses, one of which involves energy loss detection. A major means of heat energy transfer is through steam-pipes, such as the heat pipeline network which USC has in place. Thermal imagery will allow us to inventory the pipeline network, as well as to monitor it for excessive heat loss and/or leaks.
Open the image and orient yourselves to campus landmarks, such as the Horseshoe in the upper left portion of the image, or the Thomas Cooper library in the lower left portion. Although the steam pipes may be buried under concrete, soil, vegetation, and asphalt, they are visible as thin, white lines on the thermal image. If your image appears "burned out" or too bright, you may want to click the No Stretch option under the Raster tab before opening the image to disable the default 2 standard deviation histogram stretch.
12. What are the bright features found along the steam-pipes as well as at their intersection?
13. Thermal imagery will often show relief distortion perpendicular to the flight path. Was this thermal image flown east/west or north/south? What type of distortions are evident in the image? List examples that are apparent in the image.
14. After a close examination of the imagery, do you think the data was acquired in the day or night? Explain your reasoning.
15. The large building in the upper right corner of the image shows high heat loss along its sides. What might be the cause of this?
16. Most of the building roofs have brighter sections or points on them. The building immediately left of the physical plant has a large bright area on its roof. What could this be from?
17. Notice the numerous small white dots located throughout the image that are not part of the steam-line network. What might these be?
18. Explain the differences between the thermal signatures of trees and grass in the scene. If water typically is brighter than the surrounding terrain in a pre-dawn thermal image, why is the pool in front of the Cooper Library dark?
