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<p>To evaluate the potential for a new uncooled infrared radiometer imager to detect enhanced atmospheric levels of methane, three different analysis methods were examined. A single-pixel brightness temperature to noise-equivalent delta temperature (NEdT) comparison study performed using data simulated from MODTRAN6 revealed that a single thermal band centered on the 7.68&thinsp;<span class="inline-formula">µ</span>m methane feature leads to a detectable brightness temperature difference exceeding the sensor noise level for a plume of about 17&thinsp;ppm at ambient atmospheric temperature compared to an ambient plume with no enhanced methane present. Application of a normalized differential methane index method, a novel approach for methane detection, demonstrated how a simple two-band method can be utilized to detect a plume of methane that is 10&thinsp;ppm above ambient atmospheric concentration and <span class="inline-formula">−10</span>&thinsp;K from ambient atmospheric temperature with an <span class="inline-formula">80 <i>%</i></span> hit rate and <span class="inline-formula">17 <i>%</i></span> false alarm rate. This method was capable of detecting methane with similar levels of success as the third method, a proven multichannel method, matched filter. The matched-filter approach was performed with six spectral channels. Results from these examinations suggest that given a high enough concentration and temperature contrast, a multispectral system with a single band allocated to a methane absorption feature can detect enhanced levels of methane.</p>