A top-down approach for apportioning black carbon aerosols to emission sources in regions with multiple competing contributors

含碳燃料不完全燃烧产生的黑碳(BC)是导致气候变化和降低区域空气质量的两大大气污染物之一。BC的升温潜力仅次于CO2，由于其在大气中的保留时间较短，以及对各种排放源的混合、沉积和贡献知之甚少，因此对气候模拟的不确定性最大。化石燃料和生物质燃烧产生的BC具有不同的光吸收特性和老化过程，因此具有不同的升温潜势。因此，改进源特征对于确定目标、制定缓解战略以及提高气候模型中人为气溶胶输入的准确性至关重要。然而，传统的自下而上的排放清单(EI)方法具有固有的局限性，如排放因子不准确，源/汇覆盖不完整，造成很大的不确定性。

Black carbon (BC), generated from incomplete combustion of carbonaceous fuels, is one of the two major airborne pollutants that drive climate change and degrade regional air quality. With a warming potential second to CO2, BC contributes the most uncertainty to climate modeling due to its short retention time in the atmosphere and poorly understood mixing, deposition, and contribution from various emission sources. BC from fossil fuel and biomass burning possesses distinct light absorbing properties and aging processes, and hence differing warming potentials. Therefore, improved source characterization is crucial for determining targets, formulating mitigation strategies, and increasing the accuracy of input anthropogenic aerosols in climate models. However, conventional bottom-up emission inventory (EI) methods have intrinsic limitations such as inaccurate emission factors, incomplete coverage of sources/sinks that cause large uncertainties.