Satellite Observations of CO2 in support of the Paris Agreement for Emission Reduction

减缓或减缓全球变暖是21世纪人类面临的主要挑战之一。在巴黎举行的2015年联合国气候变化大会上，与会者同意减少温室气体排放，以防止全球地表温度上升超过1.5摄氏度。欧洲国家通过一系列雄心勃勃的政策和计划，将自己定位在缓解气候变化的前沿。然而，在我们对全球碳循环、其源和汇(包括人为排放)以及碳循环过程与气候变化的相互作用的理解方面，关键的知识差距阻碍了气候变化缓解政策的制定。如果我们想要推进我们对地表和大气之间的碳交换的定量理解，就需要更多和更好的观测。天基遥感方法的最新进展为提高地面网络的粗空间和时间分辨率和覆盖范围提供了机会。该项目旨在利用最近发射的一颗新卫星(GOSAT-2)来解决卫星遥感的突出局限性之一，以便在高污染(特大城市)或云层频繁覆盖(热带)的区域可靠地观测二氧化碳。除了一个强大的二氧化碳测量仪器，GOSAT-2还配备了最先进的气溶胶成像仪，因此可以对气溶胶(和云)进行详细的表征，然后为二氧化碳的提取提供信息。使用气溶胶/二氧化碳综合方法，GOSAT-2的大气二氧化碳将被绘制成地图，并用于测试当前的模型计算，以推断主要排放区域的碳表面通量信息。

Mitigating or slowing down global warming is one of the primary challenges humankind faces in the 21st century. In the 2015 United Nations Climate Change Conference held in Paris, participants agreed to reduce greenhouse gas emissions to prevent an increase of more than 1.5C in global surface temperature. European countries have positioned themselves at the forefront of climate change mitigation through a number of ambitious policies and programs. However, the development of climate change mitigation policies is hampered by critical knowledge gaps in our understanding the global carbon cycle, its sources and sinks including anthropogenic emissions and the interplay of the carbon cycle processes with climate change.More and better observations are needed if we want to advance our quantitative understanding of the carbon exchange between the surface and the atmosphere. Recent advances in space-based remote sensing methods provide opportunities to augment the coarse spatial and temporal resolution and coverage of ground-based networks.This project aims to take advantage of a new, recently launched satellite (GOSAT-2) to tackle one of the eminent limitations of satellite remote sensing to reliably observe CO2 in regions of high pollution (megacities) or frequent cloud coverage (tropics). Besides a powerful instrument for CO2, GOSAT-2 also features a state-of-the-art aerosol imager so that a detailed characterisation of aerosols (and clouds) is possible which can then inform the CO2 retrieval. Using a combined aerosol/CO2 approach, atmospheric CO2 from GOSAT-2 will be mapped and used to test current model calculations to infer carbon surface flux information focusing on major emission regions.