Evaluation of the Direct Effects of Anthropogenic Aerosols on the Radiation Balance of the Atmosphere

霍布斯/摘要 气溶胶可能在局部、区域和全球范围的大气辐射平衡中发挥重要作用。 最近的估计表明，由于人为硫酸盐的直接影响，全球平均气候强迫可能与人为“温室”气体产生的强迫在量级上相似（但符号相反）。 然而，有很大的不确定性与估计气溶胶的影响。 本研究的目的是获得对大气气溶胶的测量结果（重点是人为来源的气溶胶），以减少这些不确定性。 拟议的研究包括两项主要活动。 (a)测量气溶胶粒度分布，化学 组合物，吸湿生长因子，光散射 效率，太阳辐射的反向散射，以及 在太平洋西北部， 加州、美国东部、阿拉斯加和巴西。 (b)进行气溶胶“柱封闭”实验 美国东海岸。 影响的计算 气溶胶对太阳辐射的影响，根据详细的空气传播 物理和化学性质的测量 气溶胶，将与卫星进行比较 太阳辐射后向散射的测量 太阳辐射衰减的地面测量 辐射

Hobbs/Abstract Aerosols may plan an important role in the radiation balance of the atmosphere on local, regional and global scales. Recent estimates suggest that the globally-averaged climate forcing due to the direct effects of anthropogenic sulfate could be similar in magnitude (but opposite in sign) to that produced by anthropogenic "greenhouse" gases. However, there are large uncertainties associated with estimating the aerosol effects. The purpose of this research is to obtain measurements on atmosphere aerosols (with emphasis on those that derive from anthropogenic sources) that will reduce these uncertainties. The proposed research consists of two main activities. (a) Measuring aerosol size distributions, chemical composition, hygroscopic growth factors, light-scattering efficiency, backscattering of solar radiation, and singlescattering albedos in the Pacific Northwest, California, the eastern United States, Alaska and Brazil. (b) Conducting an aerosol "column-closure" experiment off the east coast of the USA. Calculations of the effects of aerosols on solar radiation, based on detailed airborne measurements of the physical and chemical properties of the aerosols, will be compared with satellite measurements of the backscattering of solar radiation of ground-based measurements of the attenuation of solar radiation.