摘要： Monitoring and mapping atmospheric methane is becoming increasingly important due to its role as a greenhouse gas and the fact its atmospheric concentration has been rising in recent years. Many remote sensing techniques exist to detect the presence of methane in the atmosphere including active sensing with lidar systems, passive sensing in the solar reflective spectral region, and passive sensing in the longwave thermal infrared. This study examined the temperature contrast in the longwave infrared of an enhanced concentration of methane in a near surface plume for a variety of concentrations, plume temperatures, and plume thicknesses. Results indicate radiometric temperature absolute differences for a narrow band (50 – 200 nm) centered on the 7.68 μm methane feature ranged from 0.0 to 6.8 K for the conditions studied. Future work will further validate and expand on these results.