A Raman lidar system was operated along with the Microtops sunphotometer measurements to carry out the study of the variation of the optical properties of aerosols over Palampur (32.11° N and 76.53° E), India from 17th April to 11th May 2019. The lidar system is furnished with Raman (N₂) channel and depolarization channel allowing independent measurement of Lidar Ratio (LR) and linear depolarization ratio. The study reveals that the majority of the aerosols approximately were restricted within the planetary boundary layer (PBL) and very less loading was present in the free troposphere over the study location. The particle loading over the study period was found to be very less with aerosol backscatter coefficient (at 355 nm) ranging from ∼0.13 Mm⁻¹sr⁻¹ to ∼7.25 Mm⁻¹sr⁻¹ with mean value of 2.67 ± 0.82 Mm⁻¹sr⁻¹ and it is well supplemented by the mean aerosol optical depth (AOD) of 0.37 ± 0.13 obtained from Microtops Sunphotometer. The average lidar ratio values for 0-1 km altitude (L1) 72 ± 13sr, for 1-2 km (L2) altitude 55 ± 8sr, for 2-3 km (L3) 54 ± 15sr were observed as suggesting dominance of the biomass burning aerosols and anthropogenic aerosols. The particle depolarization ratio (355 nm) values were found from approximately 4.8 ± 2.7% to 11.5 ± 1.9% with the mean value of 7 ± 1.3% suggesting the presence of non-spherical particles. To trace the sources of the pollution, we derived the HYSPLIT trajectory which shows the majority of the movement was from local sources.

拉曼激光雷达系统与 Microtops 太阳光度计测量一起运行，以研究 2019 年 4 月 17 日至 5 月 11 日印度帕拉姆普尔（32.11° N 和 76.53° E）上空气溶胶的光学特性变化。激光雷达系统配备拉曼 (N ₂ ) 通道和去极化通道，允许独立测量激光雷达比 (LR) 和线性去极化比。该研究表明，大多数气溶胶大约限制在行星边界层 (PBL) 内，并且在研究位置上空的自由对流层中存在的载荷非常少。发现研究期间的颗粒负载非常少，气溶胶后向散射系数（在 355 nm 处）范围为 ~0.13 Mm ^-1 sr ^-1至~7.25 Mm ^-1 sr ^-1，平均值为2.67 ± 0.82 Mm ^-1 sr ^-1并且得到从Microtops Sunphotometer获得的0.37 ± 0.13的平均气溶胶光学深度(AOD)的良好补充。观察到 0-1 km 高度 (L1) 72 ± 13sr、1-2 km (L2) 高度 55 ± 8sr、2-3 km (L3) 54 ± 15sr 的平均激光雷达比值表明生物量占优势燃烧气溶胶和人为气溶胶。发现粒子去极化比 (355 nm) 值从大约 4.8 ± 2.7% 到 11.5 ± 1.9%，平均值为 7 ± 1.3%，表明存在非球形粒子。为了追踪污染源，我们得出了 HYSPLIT 轨迹，该轨迹表明大部分运动来自当地。