Collaborative Research: Impacts of Global Change on Terrestrial Mercury in the Arctic

合作研究：全球变化对北极陆地汞的影响

• 批准号: 2210172
• 负责人: Kevin Schaefer
• 金额: $ 65.3万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2210172&HistoricalAwards=false
• 关键词: Collaborative; Research; Impacts; Global; Change

Northern hemisphere permafrost contains a large amount of mercury (Hg) bound to frozen organic matter. The Arctic is warming at two to three times the global average rate. As permafrost thaws, microbial decay of the organic matter will resume, releasing mercury into the environment. The scientific community lacks the process-based terrestrial mercury models needed to understand the impacts of permafrost thaw on the Arctic and global mercury cycles. This project will build such models by leveraging existing models of the terrestrial carbon cycle to advance our understanding of terrestrial mercury processes in permafrost regions at multiple temporal and spatial scales. The project will use these models to predict the pan-Arctic and global impacts of Hg released from thawing permafrost. For the first time, this project will reveal the emergent behavior of two linked components of the Arctic system: the carbon and mercury cycles.This project will leverage and enhance existing models to evaluate how Hg from thawing permafrost will influence the Arctic and global Hg cycles. The project has two objectives: 1) Quantify how different environmental conditions affect Hg accumulation with associated uncertainties; and 2) Quantify how Hg released from thawing permafrost impacts the global Hg cycle with associated uncertainties. This project uses three models of the terrestrial Hg cycle: 1) the full-physics Simple Biosphere Carnegie-Ames-Stanford Approach (SiBCASA) model; 2) the Global Terrestrial Mercury Model (GTMM) coupled to 3-D atmospheric transport and ocean circulation models; and 3) a simple Global Biogeochemical Box Model (GBBM). Simulations from 1400 to 2300 CE using SiBCASA will provide estimates of future Hg releases from thawing permafrost. Simulations with GTMM will quantify global impacts of Hg released from thawing permafrost. Monte Carlo simulations with GBBM will quantify uncertainty. These models require enhancement based on the latest knowledge of Hg uptake and release pathways. These enhancements include new biogeochemical pools such as soil water, new processes such as fire, and new computational techniques such as Monte Carlo simulations. The Broader Impacts of this project include the mentoring of early-career researchers, the organization of a training workshop to bridge the Hg and carbon research communities, and the production of publicly available products, which include an updated Hg emissions dataset, the models themselves, output from the models, and an on-line tool to visualize the model results. This project leverages extensive knowledge of terrestrial carbon pathways to parameterize Hg pathways and couple the terrestrial Hg and carbon cycles.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

北半球永久冻土包含大量与冷冻有机物的汞（HG）。 北极的变暖是全球平均率的两到三倍。 随着永久冻结的融化，有机物的微生物衰变将恢复，将汞释放到环境中。 科学界缺乏理解永久冻土对北极和全球汞周期的影响所需的基于过程的陆汞模型。 该项目将通过利用陆生碳循环的现有模型来建立此类模型，以促进我们对多个时间和空间尺度上多年冻土区域的陆生汞过程的理解。 该项目将使用这些模型来预测从融化的永久冻土释放的hg的泛氧化和全球影响。 该项目首次揭示了北极系统的两个相关组成部分的新兴行为：碳和汞周期。该项目将利用和增强现有模型，以评估从融化的永久冻土中的汞如何影响北极和全球HG周期。该项目有两个目标：1）量化不同的环境条件如何影响HG积累，而相关的不确定性；和2）量化从融化的多年冻土释放的汞如何影响全球汞周期与相关的不确定性。 该项目使用陆生汞周期的三个模型：1）全物理简单的生物圈卡内基 - 萨特福德方法（SIBCASA）模型； 2）与3-D大气传输和海洋循环模型相连的全球陆地汞模型（GTMM）； 3）一个简单的全局生物地球化学框模型（GBBM）。 使用SIBCASA从1400到2300 CE的模拟将估计从融化的永久冻土中的未来HG释放。 具有GTMM的模拟将量化从融化多年冻土释放的HG的全球影响。 具有GBBM的蒙特卡洛模拟将量化不确定性。 这些模型需要根据HG吸收和发布途径的最新知识来增强。这些增强功能包括新的生物地球化学池，例如土壤水，诸如火灾等新过程以及新的计算技术，例如蒙特卡洛模拟。 该项目的更广泛影响包括指导早期研究人员，组织培训研讨会以弥合HG和碳研究所的培训研讨会以及生产公共产品，其中包括更新的HG排放数据集，模型本身，来自模型的输出以及在线工具以可视化模型结果。该项目利用陆生碳途径的广泛知识来参数化HG途径，并将陆地HG和碳周期结合起来。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响来通过评估来支持的。