PDF(Pubmed)
Abstract：
The three-year Black Carbon (BC) aerosol measurements made during 2020, 2021, and 2022 over a rural location, namely, Panchgaon, surrounded by Aravali hillocks (elevation of about 400-600 m) have been analyzed with an aim to determine their optical and radiative characteristics, seasonal and long-term variations in mass concentration. The affinity between these parameters and associated pollutants and planetary boundary layer height (PBLH), affected by the orography, to delineate their role in mass concentration changes with time have been investigated. The coincident OPAC (Optical Properties of Aerosols and Clouds) Model-derived aerosol optical depth (AOD), and single scattering albedo (SSA) have been compared with the observed BC mass concentration, and also with synchronous satellite measurements. The year-to-year variability analysis of the data reveals that the rate of increase of BC concentration is high. The variability was low due to the reasons explained. It implies that the year-to-year variability in BC concentration at the study site depends on the source strength modulated by the valley-driven meteorology. Added, the percentage departures of BC concentration show positive values (higher concentration) during morning and evening hours, which could be due to more anthropogenic activities while it shows negative values during afternoon hours and lower boundary layer heights. The force exerted by the radiation due to BC aerosols at the bottom of the atmosphere (BOA), and in the atmosphere (ATM) are almost equal in magnitude and negative, while that at the top-of-the-atmosphere (TOA) is smaller and positive, indicating that BC aerosols in the study region cools the atmosphere at the BOA and warms the ATM and TOA, which indirectly reveals the dominant role of long-range transport phenomenon at higher levels as compared to the surface level.
摘要：
在2020年，2021年和2022年期间，在农村地区进行了为期三年的黑碳（BC）气溶胶测量，即,Panchgaon,已对被Aravali小丘（海拔约400-600m）包围的地区进行了分析，目的是确定其光学和辐射特性，质量浓度的季节性和长期变化。这些参数与相关污染物和行星边界层高度(PBLH)之间的亲和力，受地形影响，为了描述它们在质量浓度随时间变化中的作用，已经进行了研究。OPAC（气溶胶和云的光学特性）模型推导的气溶胶光学深度（AOD），并将单次散射反照率(SSA)与观察到的BC质量浓度进行了比较，还有同步卫星测量。数据的逐年变异性分析表明，BC浓度的增长率很高。由于所解释的原因，变异性很低。这意味着研究地点BC浓度的逐年变化取决于由山谷驱动的气象学调节的源强度。已添加,在早晨和晚上，BC浓度的百分比偏离显示正值（较高的浓度），这可能是由于更多的人为活动，而在下午时间和较低的边界层高度显示负值。由于大气底部的BC气溶胶（BOA）而产生的辐射所施加的力，在大气中(ATM)的大小几乎相等，而且是负值，虽然在大气层顶部（TOA）较小且为正，表明研究区域的BC气溶胶冷却了BOA处的大气，并使ATM和TOA变暖，这间接地揭示了与表面水平相比，远程传输现象在更高水平上的主导作用。
