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UV/VIS卫星仪器被送入轨道，能够以高空间分辨率绘制出NO2、HCHO和SO2等几种对流层痕量气体的全球分布。由于这些气体的大气寿命很短(几小时到几天)，这些地图可以调查源、汇的全球分布及其时间变化。这对于了解大气的组成和演变，以及对气候、生态系统或人类健康等社会相关问题的影响来说，是向前迈出的重要一步。在这里，我们建议测试和改进当前对NO2、HCHO和SO2源的全球分布的估计。首先，我们将确定不同的已知来源，并将其分配给观测到的对流层痕量气体分布。其次，通过对不同痕量物种的联合调查，我们将根据不同的排放组合来表征不同类型的污染源。在第三阶段，我们将从我们的卫星数据中量化选定来源的绝对排放量。通过将NO2、HCHO和SO2卫星地图与大气模型结果进行比较，我们将详细调查当前排放清单的质量。还将利用卫星地图通过反模拟方法对模型进行平差。特别是，后一方面需要大大提高精度的对流层卫星数据。因此，当前项目的重点放在改进大气辐射传输模式和云校正上。

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.