Sensitivity limits on optical gas imaging due to air turbulence

Infrared cameras are widely used for the detection of fugitive gas leaks and for quantifying gas emissions. While the gas detection sensitivity in the presence of noise is now well understood, we show that wind-turbulence-induced thermal fluctuations place a fundamental lower limit on gas detection sensitivity. While for many gases the lower limit is too low to be important, we show that for some gases it places a real limitation on measurements when the background is a near-ground surface.