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

减缓或减缓全球变暖是人类在21世纪世纪面临的主要挑战之一。2015年在巴黎举行的联合国气候变化大会上，与会者一致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，将自己定位在减缓气候变化的最前沿。然而，由于我们在理解全球碳循环、其源和汇（包括人为排放）以及碳循环进程与气候变化的相互作用方面存在严重的知识差距，减缓气候变化政策的制定受到了阻碍，如果我们要提高对地表和大气之间碳交换的定量理解，就需要进行更多和更好的观测。空间遥感方法的最新进展为提高空间和时间分辨率以及地面网络的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）解决卫星遥感在高污染（特大城市）或频繁云层覆盖（热带）地区可靠观测CO2方面的一个突出局限性。除了一个强大的CO2仪器外，GOSAT-2还配备了一个最先进的气溶胶成像仪，因此可以详细描述气溶胶（和云）的特征，然后为CO2反演提供信息。使用气溶胶/CO2综合方法，将对GOSAT-2号卫星的大气CO2进行测绘，并用于测试当前的模型计算，以推断侧重于主要排放区的碳表面通量信息。

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.