Identification of tropospheric emissions sources from satellite observations: synergistic use of trace gas measurements of formaldehyde (HCHO), nitrogen dioxide (NO2), and sulfur dioxide (SO2)

近年来，新一代紫外/可见卫星仪器被送入轨道，它可以以高空间分辨率绘制对流层几种微量气体如NO2、HCHO和SO2的全球分布。由于这些气体在大气中的寿命很短（几小时到几天），因此这些地图可以调查这些气体源、汇的全球分布及其时间变化。这是在了解大气的组成和演变及其对气候、生态系统或人类健康等社会相关问题的影响方面向前迈出的重要一步。在这里，我们建议测试和改进目前对NO2、HCHO和SO2来源的全球分布的估计。首先，我们将对观测到的对流层微量气体分布进行识别和分配不同的已知来源。其次，通过对不同痕量物种的综合调查，我们将根据其特定的排放组合来描述不同类型的源。在第三阶段，我们将根据卫星数据量化选定源的绝对排放量。通过将NO2、HCHO和SO2卫星图与大气模式结果进行比较，我们将详细研究当前排放清单的质量。卫星地图还将利用逆建模方法对模型进行调整。特别是后一方面需要精度大大提高的对流层卫星数据。因此，当前项目的重点是改进大气辐射传输模拟和云校正。

During recent years a new generation of UV/vis satellite instrument was put in orbit which allows to map global distributions of several tropospheric trace gases like NO2, HCHO, and SO2 at high spatial resolution. Because of short atmospheric lifetimes of these gases (hours to days), these maps allow investigation of the global distribution of sources, sinks, and their temporal changes. This is an important step forward for the knowledge of the composition and evolution of the atmosphere, and the implications for societally relevant issues, such as climate, ecosystems or human health. Here we propose to test and improve current estimates of the global distributions of sources for NO2, HCHO, and SO2. First, we will identify and assign the different known sources to the observed tropospheric trace gas distributions. Second, from the combined investigation of the different trace species we will characterize different types of sources due to their specific mix of emissions. In a third phase we will quantify the absolute emissions of selected sources from our satellite data. From a comparison of the NO2, HCHO, and SO2 satellite maps with atmospheric model results we will investigate in detail the quality of current emission inventories. The satellite maps will also be used to adjust the models by using inverse modelling method. In particular, the latter aspect requires tropospheric satellite data with largely improved accuracy. Therefore, much emphasis of the current project laid on the improvement of atmospheric radiation transfer modelling and cloud correction.