Measurements of the background methane concentration with a remote lidar on kilometer routes in the Moscow region.

Local path measurements of the background methane concentration in the northeast of the Moscow Region were carried out using a remote active lidar based on a powerful Raman amplifier of optical radiation in the wavelength range of ~ 1650 nm. The radiation power in the pulse was about 3 W. The trasses were selected taking into account possible anomalous deviations of the background of atmospheric methane and included forests, gasified buildings with natural gas, a peat lake, a road with heavy traffic, a livestock farm and a solid waste landfill. The length of the distances ranged from ~ 0.6 km to ~ 3.15 km. The highest background concentration of methane was observed over a livestock farm, over a highway and a solid waste landfill, which confirms the fact of an increase in gas emissions over these facilities. Also higher methane levels were observed above of the gasified homes and the heavy traffic road, indicating a possible increase in the number of vehicles using methane as fuel and a possible leak of natural gas from pipelines supplying buildings with natural gas.