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Thermal Remote Sensing of
Land Surface Temperature
From Satellites: Current
Status and Future Prospects
A.J. Prata
1. Introduction
• Land Surface Temperature (LST)
• > Can be computed using weather forecast models
• > Determining LST remotely could provide constraints on
model predictions
• LST Used For:
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> Evapotranspiration estimation
> Frost detection and forecasting
> Monitoring water stress in crops
> Thermal inertia studies
1. Introduction
• Difficulties with determining LST:
• > Temperature can vary widely over land
• > Temperature can change quickly
• > Definition of LST can vary depending on application
2. The Definitions Of Surface
Temperature
• 1. The radiative transfer of energy from the
surface to the atmosphere
• > Can use Stefan-Boltzmann law to calculate
• 2. Using Planck’s function
• 3. The turbulent transfer of sensible heat from
the surface
• 4. Derived from models
3. Simple and Complex Land
Surfaces
• Simple land surface
• > Surfaces that can be easily identified
• > Bare, flat terrain, fully canopy of even crops, roads, and
runways
• Complex land Surface
• > Surfaces that are vertically and horizontally
inhomoginous
• > Grasslands, forests, rough terrains
3. Simple and Complex Land
Surfaces
• Research by Marlatt (1967) to validate surface
temperature
• Placed 40 transducers over a large area of natural terran
• Terrain consisted of bare ground, rocks, and some
vegetation
• Noted very large temperature changes throughout the
area; up to 7 K in a few centimeters
• Temperatures varied in range more during the day than
at night