APPLICATION OF AIRBORNE AND GROUND-BASED HYPERSPECTRAL IMAGING IN DETECTING METHANE

Methane (CH₄) gas is colorless, odorless, and is an explosion hazard at concentrations of 5% to 15%. It is also a greenhouse gas that is much more potent than CO₂. However, unlike other greenhouse gases, CH₄ is a renewable energy source which is an economically valuable commodity. In addition, the recent discovery of traces of CH₄ on Mars has revolutionized planetary studies. Many scientists now believe that CH₄ could be used as an indicator of life on Mars and other planets. Therefore, there is a substantial need to remotely and accurately detect CH₄.

This work employs hyperspectral remote sensing techniques to remotely detect methane on airborne and ground platforms. In particular, NASA’s Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data of the massive Aliso Canyon gas leak near Porte Ranch, California, and ground-based Specim hyperspectral data of Atascosita landfill in Houston, Texas were obtained. The spectral signature of CH₄ at around 2300 nm was identified and used for image classifications. Using band ratios and spectral angle mapper (SAM) techniques, CH₄ was successfully detected in the AVIRIS and Specim data. Results indicate that conventional hyperspectral remote sensing techniques such as Spectral Angle Mapper are viable methods for detecting of CH₄. This work provides an example of detecting CH4 by hyperspectral data, and envisions broader applications of remote sensing in agricultural, industrial monitoring of greenhouse gas emissions and hydrocarbon exploration.