A Chemical History of Anthropogenic Input to the Atmosphere throughout the Industrial Era

该项目将编制1850年至2010年期间人类活动向大气排放短期污染物的历史。它将对这一时期所有主要的气溶胶种类、气溶胶前体、短寿命痕量气体、臭氧前体以及人类活动、与能源有关的燃烧和工业过程排放的主要痕量元素作出估计。这项工作是通过整合所有可用记录（从工程历史到冰芯）来约束这些物种历史的第一次尝试。技术变化和排放的趋势以前是根据工程记录制定的，并用于估计黑碳和有机碳的历史。将添加其他示踪剂的工艺特定排放，以开发多种示踪剂的时间历史。将使用国家大气研究中心开发的社区大气模型（CAM）将排放转化为大气浓度和沉积。测量的沉积历史将被制成表格，记录在湖泊沉积物和冰芯中。该项目将根据最近的极地活动更新CAM沉积参数化，特别是雪和冰。它还将利用规定的气象学40年运行，按气候模式分析向偏远地区的迁移和沉积，以评估1960年之前的迁移和沉积。将制定一项计划，通过与预测和观察到的沉积记录进行比较，获得排放技术的最佳代表。比较的主要依据是趋势，而不是绝对数量。用于优化的标记将包括源剖面中的元素比率以及源附近和远距离观测的差异。然后，优化的技术基础将提供重要的大气物种的排放。这一项目的更广泛影响包括：（一）对全球化学和迁移模型的空间和时间分辨输入，这些模型评估气候强迫变化、瞬态气候响应和短寿命化学物种的气候敏感性;（二）对地球化学循环的时间依赖性人为扰动模型的关键输入。一名研究生和两名本科生将参与这个项目

This project will develop a history of anthropogenic emissions of short-lived pollutants to the atmosphere during the period from 1850 to 2010. It will produce estimate of all major aerosol species, aerosol precursors, short-lived trace gases, ozone precursors, and major trace elements emitted from anthropogenic, energy-related combustion and industrial processes for that period. This work represents the first attempt at constraining histories of these species by integrating all available records, from engineering histories to ice cores. Trends in technology change and emission were previously developed on the basis of engineering records and used to estimate black and organic carbon histories. Process-specific emissions of other tracers will be added to develop a time history of multiple tracers. Emissions will be translated to atmospheric concentrations and deposition using the Community Atmosphere Model (CAM) developed at the National Center for Atmospheric Research. Measured histories of deposition will be tabulated as recorded in lake sediments and ice cores. This project will update the CAM deposition parameterization, particularly for snow and ice, based on recent polar campaigns. It will also conduct an analysis of transport to and deposition in remote regions by climate mode, using a 40-year run with prescribed meteorology, to assess transport and deposition prior to 1960. A scheme will be developed to obtain an optimal representation of emitting technology by comparison with predicted and observed deposition records. Trends, rather than absolute magnitudes, will be the primary basis for comparison. Markers used for optimization will include elemental ratios in source profiles and differences in observations near and far from sources. The optimized technology base will then provide emissions of the important atmospheric species. The broader impacts of this project include: (i) spatially and temporally resolved inputs to global chemical and transport models that evaluate changes in climate forcing, transient climate response, and climate sensitivities from short-lived chemical species and (ii) critical inputs to models of time-dependent anthropogenic perturbations to biogeochemical cycles. A graduate student and two undergraduate students will participate in this project