The effect of smoke aerosols on the low-level clouds over the Indian landmass during the winter season is examined using 15 years (2005–2019) of long-term multi-satellite observations and reanalyses (MERRA-2 and ERA-5) datasets. Climatologically higher values of aerosol optical depth (AOD) (> 0.6), Angstrom exponent (> 1.5), UV-aerosol index (> 0.7), and black carbon and organic carbon (BC + OC) extinction aerosol optical thickness (EXTAOT) (> 0.18) are found over the Indo-Gangetic Plain (IGP) compared to the rest of India indicating the dominance of smoke aerosols over the region. However, considerable enhancements in AOD (~ 60%) and (BC + OC) EXTAOT (20–40%) are observed over some parts of eastern India (particularly Odisha and Chhattisgarh) and central-south India compared to IGP (< 10% and < 5% respectively) in the recent years. Also, fire activities are increasing over almost the same region where smoke aerosols increased considerably, suggesting a significant role of local biomass burning (BB) in the observed rise of smoke aerosols. However, prevailing wind patterns and HYSPLIT backward air mass trajectories indicate that long-range transport from the upper IGP regions and northwestern sides of India and beyond could also increase smoke loading over this region. Climatologically, distinct spatial patterns with moderate cloud fraction (CF) (0.5–0.6) and comparatively larger liquid cloud effective radius (CER) (16–17 μm) are found over the IGP region. This study suggests that mainly low-level clouds contribute to this distinct signature of cloud distributions. However, a significant increase in CF (50–60%) is observed over almost the same region where smoke aerosols showed a considerable rise, implying the possible influence of smoke aerosols on the low-level clouds. While CF and CER showed a noticeable increase in the polluted condition, cloud optical thickness and liquid cloud water path showed a consequent decrease with increased aerosol loading. CALIPSO images suggest that mostly a mixture of dust, polluted dust, and polluted continental/smoke aerosols showed clear dominance over the inland areas, mostly confined within 2 km altitude over almost the entire study domain. However, an elevated layer of absorbing aerosols (smoke and polluted dust) over the low-level cloud increased the cloud fraction through the ‘aerosol-cloud-boundary layer’ feedback mechanism.

使用 15 年（2005 年至 2019 年）的长期多卫星观测和再分析（MERRA-2 和 ERA-5）数据集研究了冬季烟雾气溶胶对印度陆地上空低层云的影响。气溶胶光学深度 (AOD) (> 0.6)、埃指数 (> 1.5)、UV-气溶胶指数 (> 0.7) 以及黑碳和有机碳 (BC + OC) 消光气溶胶光学厚度 (EXTAOT) 的气候学值较高 ( > 0.18) 在印度恒河平原 (IGP) 上发现，与印度其他地区相比，表明烟雾气溶胶在该地区占主导地位。然而，与 IGP（< 10%和 < 5%）在最近几年。此外，在烟雾气溶胶显着增加的几乎同一地区，火灾活动也在增加，这表明局部生物质燃烧 (BB) 在观察到的烟雾气溶胶上升中发挥了重要作用。然而，盛行风模式和 HYSPLIT 后向气团轨迹表明，来自 IGP 上部地区和印度西北部及更远地区的远程传输也可能增加该地区的烟雾负荷。气候学上，在 IGP 区域发现了具有中等云分数 (CF) (0.5-0.6) 和相对较大的液体云有效半径 (CER) (16-17 μm) 的明显空间模式。这项研究表明，主要是低层云促成了这种独特的云分布特征。然而，在烟雾气溶胶显着上升的几乎同一区域观察到 CF 显着增加（50-60%），这意味着烟雾气溶胶可能对低层云产生影响。虽然 CF 和 CER 显示污染条件显着增加，但云光学厚度和液态云水路径随着气溶胶负载的增加而减少。CALIPSO 图像表明，大部分尘埃、受污染的尘埃和受污染的大陆/烟雾气溶胶的混合物在内陆地区显示出明显的优势，几乎在整个研究区域内大多局限在 2 公里的高度内。然而，低层云层上方的吸收气溶胶（烟雾和污染粉尘）的升高层通过“气溶胶-云-边界层”反馈机制增加了云的比例。