Finding and fixing gas leaks: Using urban waterways to halt the global rise in methane emissions

甲烷是一种温室气体，在20年的时间里，其全球变暖潜能值是二氧化碳的86倍——在这个时间尺度上，全球需要采取行动减少碳排放，限制灾难性的气候变化。自2010年以来，大气甲烷浓度每年增加0.5%，但要实现《巴黎气候协定》将全球变暖控制在1.5摄氏度以内的目标，在2010年至2050年期间，大气甲烷浓度需要每年减少0.9%。目前大气中大约一半的甲烷来自人类活动，因此解决人类驱动的甲烷排放问题对于实现气候目标至关重要。这项奖学金将使我能够组建一个团队，帮助解决全球甲烷排放量上升的问题。这将通过三个工作包（WPs）来实现，这些工作包将为减少人类驱动的甲烷排放的关键挑战提供技术解决方案。这些技术解决方案将被开发并应用于城市水道（城市河流和运河），因为这些系统可以作为人为驱动的甲烷排放到大气中的管道。城市水道可以接收各种各样的甲烷输入，如泄漏的气体和污水管道，并且将承受越来越大的人类压力，预计到2030年将有超过50亿人居住在城市。我们如何准确地测量甲烷排放量？甲烷排放在短的空间（米）和时间（小时）尺度上变化很大。该奖学金将提供测量甲烷排放的仪器，其空间和时间分辨率远远超过目前的能力，并利用它来量化全球代表性地区（英国、欧洲、美国、中国、孟加拉国）城市水道对城市规模甲烷库存的贡献。甲烷排放来自哪里？甲烷排放可以由人类活动（如管道泄漏）直接驱动，也可以通过增加水道中甲烷的产量间接驱动。该研究项目使用的技术将通过测量甲烷/乙烷比率和甲烷稳定同位素（C-13），以与WP1相同的高分辨率区分自然甲烷和人为甲烷。这将与目标甲烷放射性同位素（C-14）和稳定同位素（H-2）以及城市水道的地球化学和微生物特征相结合。将绘制整个城市水运网络的甲烷排放和来源图，以确定甲烷向大气释放的关键控制。WP3。我们如何减少甲烷的排放？控制甲烷释放的地图，加上通过原位和实验室孵化的详细微生物特征，将用于提供技术，以a)检测甲烷泄漏，甚至隐藏在地下的泄漏，b)通过开发生物修复策略防止人类驱动的甲烷排放到大气中。例如，城市水道微生物如何应对甲烷泄漏，我们能否利用这些微生物在泄漏的甲烷到达大气之前迅速氧化？由于潜在的人为甲烷来源范围广泛，城市水道为所提出的技术提供了一个强有力的试验台。这些技术将作为研究、工业和政策最终用户的工具箱提供。该工具箱将通过一个由研究和行业主导的指导委员会，与壳牌和英国环境署等项目合作伙伴合作开发。该奖学金提供灵活性、培训和所需时间，以提供以用户为中心的工具箱，其中包括：1)捕获甲烷排放的时空变化的仪器；2)免费提供的甲烷同位素参考数据库以及相关的地球化学和微生物特征，以确定甲烷的来源；3)检测和减少人为甲烷排放到大气的切实解决方案；与行业和政策重点伙伴合作开发。

Methane is a greenhouse gas with 86 times the global warming potential of carbon dioxide over a 20-year period - the timescale in which global action to reduce carbon emissions and limit catastrophic climate change is needed. Atmospheric methane concentrations have increased by 0.5% per year since 2010, yet to achieve the Paris Climate target limiting global warming to 1.5 degrees Celsius it needs to decrease by 0.9% per year between 2010 and 2050. Roughly half the methane currently in the atmosphere comes from human activity, so addressing human-driven methane emissions is crucial to achieving climate targets.This fellowship will allow me to build a team to help address the global rise in methane emissions. This will be achieved via three work packages (WPs) that deliver technical solutions to key challenges standing in the way of a reduction in human-driven methane emissions. These technical solutions will be developed and applied in urban waterways (city rivers and canals) because these systems can act as conduits for human-driven methane emissions to the atmosphere. Urban waterways can receive a wide range of methane inputs, such as leaky gas and wastewater pipes, and will come under increasing human pressure with more than 5 billion people predicted to live in cities by 2030.WP1. How do we accurately measure methane emissions? Methane emissions can vary substantially over short spatial (meters) and temporal (hours) scales. The fellowship will deliver instrumentation that can measure methane emissions at spatial and temporal resolutions far surpassing current capabilities, and use it to quantify the contribution of urban waterways to city-scale methane inventories across globally representative locations (UK, Europe, USA, China, Bangladesh).WP2. Where do methane emissions originate? Methane emissions can be driven directly by human activity, such as leaky pipes, or indirectly by increasing the production of methane in waterways. The techniques used in this fellowship will distinguish natural from human-driven methane by measuring methane/ethane ratios and methane stable (C-13) isotopes at the same high resolutions as in WP1. This will be coupled with targeted methane radio- (C-14) and stable (H-2) isotopes, and geochemical and microbial characterisation of urban waterways. Methane emissions and origin will be mapped out for entire urban waterway networks to determine the key controls of methane release to the atmosphere. WP3. How do we reduce methane emissions? The mapping of controls on methane release, coupled to detailed microbial characterisation through in-situ and lab incubations, will be used to deliver techniques to a) detect methane leaks, even ones hidden underground, and b) prevent the emission of human-driven methane to the atmosphere by developing bioremediation strategies. For example, how do urban waterway microbes respond to methane leaks, and can we utilise these microbes to rapidly oxidise leaking methane before it reaches the atmosphere?With a wide range of potential human-driven methane sources, urban waterways provide a strong testbed for the proposed techniques. These techniques will be delivered as a toolbox for research, industry and policy end-users. The toolbox will be developed in collaboration with project partners such as Shell and the UK Environment Agency via a research and industry-led steering committee (see letters of support). This fellowship provides the flexibility, training and time required to deliver a user-focused toolbox containing:1) instrumentation to capture the spatial and temporal variability of methane emissions2) a freely available reference database of methane isotopes and associated geochemical and microbial signatures to identify methane origins3) tangible solutions to detect and reduce human-driven methane emissions to the atmosphere, developed in collaboration with industry and policy focused partners.