Collaborative Research: NSFGEO-NERC: Recent changes in Arctic biogenic sulfur aerosol from a central Greenland ice core

合作研究：NSFGEO-NERC：格陵兰中部冰芯北极生物硫气溶胶的最新变化

• 批准号: 2230350
• 负责人: Becky Alexander
• 金额: $ 62.74万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2230350&HistoricalAwards=false
• 关键词: Collaborative; Research; NSFGEO; NERC; Recent

This is a project jointly funded by the National Science Foundation’s Directorate for Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award recommendation, each Agency funds the proportion of the budget that supports scientists at institutions in their respective countries.Sulfur aerosols cool the climate. The amount of sulfur aerosol in the Arctic has varied dramatically in the recent past due mostly to sulfur aerosol from coal combustion. Sulfur emissions from coal combustion increased at the onset of the Industrial Revolution and have been decreasing since the 1970s because of the implementation of policies in the US and Europe to reduce air pollution. As human emissions decline, natural sulfur sources, such as from microscopic plants in the ocean, are becoming more important. The ocean biological source of sulfur aerosol may also be changing with a changing Arctic climate, particularly due to the melting of sea ice. This project will measure the two main chemical sources of sulfur aerosol in the Arctic, methane sulfonic acid (MSA) that is only from ocean biology, and sulfate, that originates from ocean biology, volcanoes, and combustion of coal and oil. The project will measure the sulfur isotopic composition of the chemicals in order to distinguish the ocean biological source from the other two sources and determine how large each source is and how fast each is changing. These measurements will provide a way to determine if and how ocean microscopic plants and their sulfur emissions are responding to Arctic climate change. This project will support the training of two graduate students and several undergraduate students. The students and PIs will participate in local outreach events in Seattle, WA and in Brookings, SD. We will work with the School of Ice to produce a new Virtual Field Lab geared towards students from middle school through early college. Ice-core observations of methane sulfonic acid (MSA) are used as a proxy for past oceanic biogenic productivity because MSA originates solely from the oxidation of dimethyl sulfide (DMS) emitted by ocean phytoplankton. Previous research using Greenland ice cores showed a detectable MSA decline since the 1800s, implying decreasing oceanic biogenic productivity. The use of MSA as a proxy for biogenic productivity relies on the assumption that the branching ratio of production of MSA versus sulfur dioxide (SO2) from DMS oxidation remains constant over time. However, recent examination of MSA and isotopic composition of sulfate in Greenland ice cores over the last 800 years shows that the ratio of MSA-to- biogenic sulfate (MSA/bioSO4) has not remained constant. This project hypothesizes that recent trends in MSA are driven by changes in oxidant abundances (e.g., NOx) that lead to a reduced yield of MSA and increased yield of SO2 during oxidation of DMS. The project will test this hypothesis by measuring ion and MSA concentrations and sulfur isotopes of sulfate in Greenland snow accumulated over the last 30 years. The last 30 years will cover the time when anthropogenic NOx emissions from North America and Europe began to decline (after the mid-1990s). In collaboration with University of St. Andrews in United Kingdom, the project will also measure sulfate isotopes at sub-seasonal resolution over the last 30 years from the proposed shallow ice cores in addition to select, discrete samples from archived ice in the preindustrial. Measuring biogenic sulfate at seasonal resolution since the preindustrial will allow for investigation of changes in the seasonality of biogenic sulfur aerosol in the Arctic resulting from changes in Arctic climate. To assist data interpretation, the global chemical transport model GEOS-Chem will be used to quantify the role of different oxidants on DMS oxidation as these oxidants have changed due to anthropogenic emissions. This project has broad implications for the ice-core, climate, and atmospheric chemistry communities because the results will improve our understanding of the impacts of Arctic climate change and anthropogenic emissions on biogenic sulfur aerosols, and thus our understanding of a potentially important climate feedback at high latitudes and future climate projections. This project will support the training of two graduate students and several undergraduate students at the UW and SDSU in ice-core processing, chemical and isotopic analysis, global modeling, and international collaboration. The students and PIs will participate in local outreach events in Seattle, WA and in Brookings, SD. The team will work with the School of Ice to produce a new Virtual Field Lab geared towards students from middle school through early college. The first-time partnership with University of St. Andrews will enhance scientific outcomes.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.

这是一个由国家科学基金会地球科学局（NSF/GEO）和英国国家环境研究委员会（NERC）共同资助的项目，该项目通过NSF/GEO-GEO-NERC领先机构协议。该协议允许该机构提交和同行评审的一项联合提案，其调查员的预算比例最大。在成功确定奖励建议后，每个机构都资助了支持各自国家机构的科学家的预算比例。硫磺气溶胶凉爽。在最近，北极中硫气溶胶的量大大变化，这主要是由于煤组合的硫气溶胶。工业革命开始时煤炭组合的硫排放量增加，自1970年代以来一直在减少，因为在美国和欧洲实施政策以减少空气污染。随着人类排放的下降，天然硫来源（例如海洋中的微观植物）变得越来越重要。硫气溶胶的海洋生物学来源也可能随着北极气候变化而改变，特别是由于海冰融化。该项目将测量仅来自海洋生物学和硫酸盐的甲烷磺酸（MSA）中硫气溶胶的两个主要化学源，这些化学物质来自海洋生物学，火山和煤炭和石油的组合。该项目将测量化学物质的硫同位素组成，以将海洋生物学来源与其他两个来源区分开，并确定每个来源的大小以及每个来源的变化速度。这些测量结果将提供一种方法，以确定海洋微观植物及其硫排放量如何以及如何应对北极气候变化。该项目将支持两名研究生和几名本科生的培训。学生和PI将参加华盛顿州西雅图市的当地外展活动，并参加SD的布鲁金斯。我们将与ICE学院合作，生产一个针对中学到早期大学的学生的新虚拟实验室。甲烷磺酸（MSA）的冰核观察结果被用作过去海洋生物生产力的代理，因为MSA仅起源于海洋浮游植物发出的二甲基硫化物（DMS）的氧化。以前使用格陵兰冰核的研究表明，自1800年代以来，MSA可检测到下降，这意味着海洋生物生产力降低了。使用MSA作为生物生产力的代理取决于以下假设：从DMS氧化中，MSA的生产比MSA的分支比MSA的生产比（SO2）随着时间的流逝而保持恒定。然而，最近800年中，最近检查了格陵兰冰核中硫酸盐和同位素组成的研究表明，MSA与生物生物源性硫酸盐的比率（MSA/Bioso4）并不保持恒定。该项目假设MSA的最新趋势是由氧化剂丰度（例如NOX）的变化驱动的，这些变化导致MSA产量降低，而DMS氧化过程中SO2的产量增加。该项目将通过测量过去30年中硫酸盐中硫酸盐的离子和MSA浓度以及硫酸盐同位素来检验这一假设。过去30年将涵盖北美和欧洲的人为NOX排放开始（1990年代中期之后）的时间。 In collaboration with University of St. Andrews in United Kingdom, the project will also measure sulfate isotopes at sub-seasonal resolution over the last 30 years from the proposed shallow ice cores in addition to select, discrete samples from archived ice Measuring biogenic sulfate at seasonal resolution since the prenuclear will allow for investment of changes in the seasonality of biogenic sulfur aerosol in the Arctic resulting from changes in Arctic climate.为了帮助数据解释，全球化学转运模型地理化模型将用于量化不同氧化物在DMS氧化中的作用，因为这些氧化物由于人为排放而发生了变化。该项目对冰核，气候和大气化学群落具有广泛的影响，因为结果将提高我们对北极气候变化和人为发射对生物硫气溶胶的影响的理解，因此我们对高纬度和未来攀登项目的潜在重要攀登反馈的理解。该项目将支持在UW和SDSU的两名研究生和几名本科生的培训，以冰核加工，化学和同位素分析，全球建模和国际合作培训。学生和PI将参加华盛顿州西雅图市的当地外展活动，并参加SD的布鲁金斯。该团队将与ICE学校合作，生产一个针对中学到早期大学的学生的新虚拟实验室。与圣安德鲁斯大学的首次合作伙伴关系将增强科学成果。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响标准，被认为值得通过评估来获得支持。