College of Science
This study investigated the use of LibRadtran to calculate "pixel-size" spectral profiles of the Earth’s surface to understand and improve atmospheric corrections of satellite imagery. LibRadtran is a publicly available library of radiative transfer packages used in studies from a variety of scientific fields to compute radiance values, irradiance values, and actinic fluxes in different spectral regions. While widely used as a package for calculating the transfer of radiation within Earth’s atmosphere, few studies have compared its results to other atmospheric models more prevalent in remote sensing such as QUick Atmospheric Correction and Dark Object Subtraction. Utilizing the uvspec model within LibRadtran, atmospheric profile data from local ozonesonde flights, and satellite measurements from Sentinel-2A and Sentinel-5P TROPOspheric Monitoring Instrument, several spectral profiles were produced for different land types, including forest, concrete, grass and water. Each spectral profile output was plotted in Python to visualize the data before calculating the differences in the three methods. An Analysis of Variance showed that the radiance means of each method vary heavily depending on the land cover type. Concrete and forest varied the most when compared to LibRadtran calculations. These results suggest that the spectral profiles calculated by LibRadtran rely heavily on the albedo profiles specified, which can differ from the “ground-truth.” Further investigation into the model’s weight on the atmosphere parameters is imperative in determining LibRadtran’s effectiveness and accuracy when correcting satellite imagery.
"Statistical Comparison Between Various Atmospheric Correction Methods and the LibRadtran Package,"
Perpetua: The UAH Journal of Undergraduate Research: Vol. 4:
2, Article 4.
Available at: https://louis.uah.edu/perpetua/vol4/iss2/4