Relating Landsat digital count values to ground reflectance for optically thin atmospheric conditions

Area of Science:

• Remote Sensing
• Earth Observation

Background:

• Landsat digital count (DCc) data require calibration for accurate reflectance estimation.
• Ground-measured bidirectional reflectance (R) is crucial for surface characterization.

Purpose of the Study:

• To consolidate data from seven investigations relating Landsat DCc to ground-measured R.
• To derive a simplified linear formulation for estimating R from DCc.

Main Methods:

• Summarizing and examining data from seven separate investigations.
• Correcting original Landsat digital count (DCo) to DCc using sun zenith angle and calibration period.
• Deriving linear regression models for R estimation from DCc.

Main Results:

• Significant agreement was found across the seven data sources in estimating R from DCc.
• A simplified linear formulation was derived for optically thin atmospheres.
• Specific linear relations were established for different Landsat bands (R4, R5, R6, R7).

Conclusions:

• The derived linear formulation provides a reliable method for estimating bidirectional reflectance from Landsat DCc.
• The model is applicable under conditions approximating optically thin atmospheres.
• This work enhances the utility of Landsat data for surface reflectance studies.