Remote measurement of ethylene using a CO_2 differential-absorption lidar

Abstract
Ethylene has been monitored with a single-ended CO2 lidar using topographical scattering. Foliage on the foothills 5 km away provided the backscattered signal. Interference due to water vapor was found to be equivalent to 7.6 ppb of ethylene, and this correction was applied to the data. The total measurement uncertainty was found to average 1.6 ppb. The lidar-measured concentrations agree with point monitor samples over a wide range of ambient concentrations.