Thermal Infrared (TIR)
Definition
Sensor bands measuring emitted heat radiation (approximately 8-14 micrometres). Decomposing organic matter generates heat; soil with high moisture retains heat longer than dry soil. TIR detects these temperature contrasts against the background thermal field.
- Wavelength band
- About 8 to 14 micrometres
- Measures
- Emitted heat radiation
- Decomposition signal
- Heat from decomposing organic matter
- Soil effect
- Moist soil retains heat longer than dry soil
Common questions
Why does soil moisture complicate TIR interpretation of a burial?+
A disturbed grave often holds moisture differently than the surrounding ground, so the thermal contrast an analyst sees may reflect soil compaction and drainage as much as decomposition heat, requiring corroborating evidence before conclusions are drawn.
When is TIR most useful for locating remains?+
It performs best during a narrow window, typically at dawn or dusk when background ground temperature is more uniform, making a localised thermal anomaly from a shallow grave or recent decomposition stand out more clearly.
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- Synthetic Aperture Radar (SAR)
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- Temporal Change Detection
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