Methane Production in the Arctic: Under-recognized Cold Season and Upland Tundra - Arctic Methane Sources-UAMS

北极的甲烷生产：未被充分认识的寒冷季节和高地苔原 - 北极甲烷来源-UAMS

• 批准号: NE/P002552/1
• 负责人: Donatella Zona
• 金额: $ 11.46万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FP002552%2F1
• 关键词: Methane; Production; Arctic; Under; recognized

In this project, we will use state of the art approaches and knowledge to better understand the current patterns of and controls on methane (CH4) release from the Arctic to the atmosphere and to improve major models to better simulate future releases of CH4 from the Arctic as the planet warms. Atmospheric methane (CH4) is the second most important greenhouse gas (after CO2) that has strong anthropogenic origins. High northern latitude terrestrial ecosystems account for ca. 50% of extra-tropical biogenic wetland emissions. More importantly methane emissions from the Arctic could increase dramatically in the future. The very large organic carbon stocks (>1,300 GtC) in the top 3 m of Arctic soils and the rapid climate change experienced and predicted in the Arctic, results in a very real possibility of large biogenic CH4 release from these soils in this century. Despite the importance of CH4 fluxes from the Arctic, now and in the future, biogenic and total natural CH4 emissions are poorly understood and very poorly modelled (Fisher et al., 2014).In 2013, we updated five eddy covariance (EC) towers in Arctic Alaska to operate reliably year-round and measure CH4 fluxes. Initial measurements yielded two unexpected and highly significant findings: 1) cold season CH4 emissions account for >50% of annual emissions and 2) drier upland tundra are larger emitters of CH4 than wetter inundated tundra (Zona et al 2016 PNAS). These observations and processes are not now incorporated in leading global land-surface/carbon-cycle models used to calculate current and predict future CH4 emissions from the Arctic. Verifying this new understanding and incorporating this understanding into models used in the UK and elsewhere will revolutionize our ability to accurately calculate and model terrestrial CH4 fluxes. These results, if supported by the outputs of this project, are critical to verifying current baseline emissions, detecting a changing baseline, and for predicting, with confidence, biogenic CH4 emissions from the Arctic in the future. This project has two overarching objectives: (1) determining the patterns of, controls on, and importance of cold season and upland tundra in Arctic CH4 emissions; (2) incorporating this understanding into JULES, LPJ and TCF, thus significantly improving our ability to estimate current and predict future CH4 fluxes in the Arctic. This work is expected to impact policy through new information and model development, reported through conferences and publications and referenced in upcoming IPCC reports. In the project, we will continue year-round observation of methane release to the atmosphere, and the atmospheric and soil environment that corresponds to these fluxes. We will initiate new experiments and observations to understand the processes and conditions controlling the observed CH4 fluxes including a new system of measurement of CO2, CH4, and 222Rn concentrations that allow autonomous, year-round, determination of CH4 production, consumption, and flux by soil depth and snow layer. We will measure year-round [CH4] and d13CH4 will help identify the importance of methane oxidation in surface soil layers at different locations and seasons. And we will determine the role of GPP in controlling rates of CH4 production. We will also determine the importance of vascular plants in providing a conduit for CH4 produced at depth, to escape to the atmosphere past an oxidizing surface layer. This new information will inform model development and improvement of models used by the Arctic community. Performance of these models will verified with unique data sets not used in model development. As a result, we intend UAMS to have a major impact on the communities' ability to calculate current and to predict with confidence future Arctic CH4 emissions in a changing world and thereby better inform policy decisions.

在这个项目中，我们将利用最先进的方法和知识来更好地了解北极向大气中甲烷（CH4）释放的当前模式和控制，并改进主要模型以更好地模拟未来甲烷（CH4）从北极的释放随着地球变暖。大气甲烷 (CH4) 是第二重要的温室气体（仅次于二氧化碳），具有很强的人为来源。北高纬度陆地生态系统约占。热带生物湿地排放量的 50%。更重要的是，未来北极的甲烷排放量可能会急剧增加。北极土壤表层 3 m 的有机碳储量非常大（>1,300 GtC），加上北极经历和预测的快速气候变化，导致本世纪这些土壤极有可能释放大量生物 CH4。尽管来自北极的 CH4 通量很重要，但现在和未来，人们对生物源排放和总自然 CH4 排放知之甚少，建模也很差（Fisher 等人，2014 年）。2013 年，我们更新了 5 个涡流协方差 (EC) 塔位于阿拉斯加北极地区，全年可靠运行并测量 CH4 通量。初步测量得出了两个意想不到且非常重要的发现：1) 冷季 CH4 排放量占年排放量的 50% 以上，2) 干燥的高地苔原比湿润的淹没苔原是更大的 CH4 排放源（Zona 等人，2016 年 PNAS）。这些观测结果和过程目前尚未纳入用于计算北极当前和预测未来 CH4 排放的全球领先陆地表面/碳循环模型中。验证这一新的认识并将其纳入英国和其他地方使用的模型中，将彻底改变我们准确计算和模拟陆地 CH4 通量的能力。如果得到该项目成果的支持，这些结果对于验证当前基线排放、检测基线变化以及自信地预测未来北极的生物甲烷排放至关重要。该项目有两个总体目标：(1) 确定冷季和高地苔原在北极 CH4 排放中的模式、控制和重要性； (2) 将这一理解纳入 JULES、LPJ 和 TCF，从而显着提高我们估计北极当前和预测未来 CH4 通量的能力。这项工作预计将通过新信息和模型开发影响政策，并通过会议和出版物进行报告，并在即将发布的 IPCC 报告中引用。在该项目中，我们将继续全年观测甲烷向大气的释放，以及与这些通量相对应的大气和土壤环境。我们将启动新的实验和观察，以了解控制观察到的 CH4 通量的过程和条件，包括一个新的 CO2、CH4 和 222Rn 浓度测量系统，该系统允许全年自主确定 CH4 生产、消耗和通量土壤深度和雪层。我们将全年测量 [CH4] 和 d13CH4 将有助于确定不同地点和季节表土层中甲烷氧化的重要性。我们将确定 GPP 在控制 CH4 产量中的作用。我们还将确定维管束植物在为深层产生的 CH4 提供通道以通过氧化表面层逃逸到大气方面的重要性。这些新信息将为北极社区使用的模型开发和改进提供信息。这些模型的性能将使用模型开发中未使用的独特数据集进行验证。因此，我们希望 UAMS 对社区在不断变化的世界中计算当前北极 CH4 排放量并充满信心地预测未来北极 CH4 排放量的能力产生重大影响，从而更好地为政策决策提供信息。

项目成果

Snow melt stimulates ecosystem respiration in Arctic ecosystems

• DOI: 10.1111/gcb.15193
• 发表时间: 2020-06-30
• 期刊: GLOBAL CHANGE BIOLOGY
• 影响因子: 11.6
• 作者: Arndt, Kyle A.;Lipson, David A.;Zona, Donatella
• 通讯作者: Zona, Donatella

Representativeness of Eddy-Covariance flux footprints for areas surrounding AmeriFlux sites

• DOI: 10.1016/j.agrformet.2021.108350
• 发表时间: 2021-02-14
• 期刊: AGRICULTURAL AND FOREST METEOROLOGY
• 影响因子: 6.2
• 作者: Chu, Housen;Luo, Xiangzhong;Zona, Donatella
• 通讯作者: Zona, Donatella

Upscaling CH4 Fluxes Using High-Resolution Imagery in Arctic Tundra Ecosystems

• DOI: 10.3390/rs9121227
• 发表时间: 2017-12-01
• 期刊: REMOTE SENSING
• 影响因子: 5
• 作者: Davidson, Scott J.;Santos, Maria J.;Zona, Donatella
• 通讯作者: Zona, Donatella

Addressing biases in Arctic-boreal carbon cycling in the Community Land Model Version 5

解决社区土地模型版本 5 中北极-北方碳循环的偏差

• DOI: 10.5194/gmd-14-3361-2021
• 发表时间: 2021
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Birch L

Arctic greening associated with lengthening growing seasons in Northern Alaska

• DOI: 10.1088/1748-9326/ab5e26
• 发表时间: 2019-12-01
• 期刊: ENVIRONMENTAL RESEARCH LETTERS
• 影响因子: 6.7
• 作者: Arndt, Kyle A.;Santos, Maria J.;Zona, Donatella
• 通讯作者: Zona, Donatella