The Global Methane Budget

全球甲烷预算

基本信息

批准号：
NE/N016092/2
负责人：
Yit Arn Teh
金额：
$ 13.69万
依托单位：
Newcastle University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2019
资助国家：
英国
起止时间：
2019 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FN016092%2F2
关键词：
Global Methane Budget

项目摘要

Methane is the second most important greenhouse gas contributing to human-induced global warming. Atmospheric methane concentrations have increased sharply since 2007, and dramatically in 2014, for reasons that are not understood. The overall increase since 2007 is comparable to the largest growth events over the past 1000 years. The recent rises have occurred worldwide, but after an Arctic pulse in 2007, the growth has been primarily in the tropics and southern hemisphere. Strong growth continues in 2015. Carbon isotopic evidence suggests that the increase is due to sources that are predominantly biogenic in origin, with changes in the anthropogenic sources from fossil carbon and burning (e.g., natural gas leakage, coal mining and so on) playing a subordinate role. This, taken with the tropical locus on growth, suggests that the increase has primarily been driven by meteorological change (e.g., temperature, rainfall). Moreover, the global methane budget is currently not well understood. "Bottom-up" estimates, made by aggregating inventories of emissions (e.g. from gas leaks, fires, landfills, cows, etc) or from process models (e.g., wetlands) balanced with known loss processes, are significantly different from '"top-down" budgets assessed by direct measurement of methane in the atmosphere. Why this discrepancy occurs is not known.The project has four components:1. Better Observations are needed to derive estimates of emissions. The project will support a UK observation network for methane and its isotopes. Continuous stations will be at Kjolnes (Norway), Weybourne, Jersey, NERC ship RRS JC Ross, Cape Verde, Ascension, Falklands, Halley Bay, Hong Kong, with partner stations in Canada, Spitsbergen, Bolivia, S. Africa, India, Rwanda and Malaysia. Flask or bag sampling (for methane, 13C and D/H isotopes) will also be undertaken at these stations and at a number of continental stations in S. America, Africa and S, SE and E Asia, with offline analysis in the UK. A D/H measurement facility will be set up. The UK FAAM aircraft will carry out flights across the Atlantic tropics, from Azores to Cape Verde to Ascension.2. Process Studies will address the largest information gaps in the global budget. Tropical emission fluxes and isotopic signatures are not well constrained. Field campaigns will be undertaken in tropical wetlands in Amazonia, Africa, India and SE Asia, and C4 savanna biomass burn regions. Poorly understood anthropogenic sources will be studied in Kuwait and S, SE and E Asia. Characteristic isotopic signatures of regional emissions will be determined, to support global and regional modelling. Land surface modelling and satellite studies will study emissions and responses to change in temperature and precipitation. Major sink processes will be investigated in the tropical atmosphere, with vertically and latitudinally resolved OH and Cl budget studies by the FAAM aircraft, and quantification of tropical uptake by soils.3. Atmospheric modelling will be used to derive regional and global fluxes, apportioned by source type and geography using integrated in situ and remote sensing observing systems. We will carry out regional trajectory studies using models like NAME to assess regional emissions. Global modelling using 3D models will test synthetic estimates of the methane mole fraction and isotopic record. Global inverse modelling for mole fraction, 13C and D/H will be used to estimate fluxes by geographic source and source type, including a comprehensive assessment of the uncertainties that remain once all available observations have been used.4. Integrative studies will use the results from the project to test top-down and bottom-up emission estimates, and evaluate the responses of the global methane budget to projections of climate change.The project will deliver a state of the art greenhouse gas monitoring network and much better knowledge of the global methane budget.

甲烷是促成人类引起的全球变暖的第二重要温室气体。自2007年以来，大气中的甲烷浓度急剧增加，并且在2014年急剧增加，原因是尚不清楚。自2007年以来的总体增长与过去1000年中最大的增长事件相当。最近的上升发生在全球范围内，但是在2007年北极脉搏之后，增长主要是在热带地区和南半球。强劲的增长在2015年持续。同位素的碳同位素证据表明，增加是由于来源的起源主要是生物基因的，并且来自化石碳和燃烧的人为来源的变化（例如天然气泄漏，煤炭挖掘等）的变化从属角色。这是由热带基因座的生长所采用的，这表明增加主要是由气象变化驱动的（例如温度，降雨）。此外，全球甲烷预算目前尚不清楚。 “自下而上”的估计值是通过汇总排放清单（例如气体泄漏，火灾，垃圾填埋场，牛等）或从已知损失过程平衡的过程模型（例如湿地）与'顶 - 下降”通过直接测量大气中的甲烷评估的预算。为什么不知道这种差异发生。该项目有四个组成部分：1。需要更好的观察以得出排放的估计。该项目将支持甲烷及其同位素的英国观察网络。连续电台将在Kjolnes（挪威），Weybourne，泽西岛，NERC Ship RRS JC Ross，Cape Verde，Cape Verde，Aspension，Aspension，Falklands，Falklands，Halley Bay，Hongy Bay，Hong Kong，与加拿大的合作伙伴电台，Spitsbergen，Bolivia，Bolivia，S。Africa，S. Africa，India，India，Rwanda，Rwanda，Rwanda，Rwanda，Rwanda和马来西亚。还将在英国的离线分析中在这些车站和许多大陆车站进行烧瓶或袋采样（对于甲烷，13C和D/H同位素），在S. America，Africa和S，SE，SE和EASIA的许多大陆站进行。将建立D/H测量设施。英国FAAM飞机将在大西洋热带地区进行航班，从亚速尔群岛到佛得角到升天。2。过程研究将解决全球预算中最大的信息差距。热带发射通量和同位素特征受到良好的约束。现场运动将在亚马逊，非洲，印度和SE亚洲的热带湿地以及C4 Savanna Biomass Burn地区进行。在科威特和S，SE和E亚洲，将研究知识渊博的人为来源。将确定区域排放的特征同位素特征，以支持全球和区域建模。陆地表面建模和卫星研究将研究对温度和降水变化的排放和反应。主要的下水道过程将在热带气氛中进行研究，并通过FAAM飞机进行垂直和纬度分析的OH和CL预算研究，并通过土壤对热带摄取进行定量。3。大气建模将用于得出区域和全局通量，使用集成的原位和遥感观测系统分配给源类型和地理。我们将使用名称等模型进行区域轨迹研究来评估区域排放。使用3D模型的全局建模将测试甲烷摩尔分数和同位素记录的合成估计。摩尔分数，13c和d/h的全局反向建模将用于估计地理源和源类型的通量，包括对所有可用观察结果一旦使用的不确定性进行全面评估。4。综合研究将利用项目的结果来测试自上而下和自下而上的排放估算，并评估全球甲烷预算对气候变化预测的反应。该项目将提供最先进的温室气体监测网络和更好地了解全球甲烷预算。