Ecological Systems and Devices Annotation << Back Measurements of Methane Background Distribution Inhomogeneity by Fiber Optical Lidar in a Suburban Area of the Moscow Region Grigorievsky V.I., Sadovnikov V.P., Tezadov Ya.A., Elbakidze A.V. Using a prototype of a remote lidar created in the laboratory for measuring methane concentration, a study of the distribution of methane along a route ~2,25 km long was carried out in order to localize gas emissions and control leaks in unfavorable areas. The lidar prototype, operating at a wavelength of 1653 nm, included a powerful Raman amplifi er and made it possible to measure the distance to the refl ection point with an accuracy of no worse than 50 meters. The lidar scanned the track, starting from short distances and ending with measurements along the entire measured track. The route included a near zone with modern multi-storey buildings without gas infrastructure, a middle zone with multi-storey buildings and gas infrastructure, as well as an extended forest area ending with a busy highway with heavy traffi c. That is, it was possible to assess the contribution of each zone to the background methane concentration along the route. Observations were carried out during the winter-spring period and were carried out at different times of the day under weather conditions that were recorded. Processing of the results showed a signifi cantly different contribution of each zone to the average concentration on the route. The contribution of the middle zone with multi-storey buildings equipped with gas infrastructure turned out to be especially large, which suggests a possible gas leak from the gas distribution system in this area. On average, the background concentration of methane on this route repeated the value measured in 2023 during the same seasonal period in 2023. Keywords: tomographic method, lidar, atmosphere, concentration, methane, resolution, gas leaks. DOI: 10.25791/esip.9.2024.1470 Pp. 03-09.