Collaborative Research: Responses of atmospheric oxidants and CO2 to dramatic changes in Arctic sea ice

北极地区具有独特的大气化学性质，会对人类健康产生积极和消极的影响，例如地面臭氧消耗和汞沉积。海水中大气二氧化碳的吸收，受到随时间变化的海冰覆盖量的调节，导致北冰洋水域酸化，对海洋生态系统产生潜在的重要影响。人们预计，大气及其化学成分将以复杂的方式对海冰变化和北极变暖作出反应，但科学界仅凭对相关过程的基本机制了解，缺乏自信地做出预测的能力。 O-浮标化学网络项目由北极观测网络拨款资助，旨在观测大气化学物质、气象学和海冰特性，从而提高我们对相关过程的理解，从而提高对未来气候情景的可预测性。该项目部署了十五个自主浮标，测量遍布北冰洋的三种哨兵大气化学物质，每个化学物质持续大约一年的时间，提供详细的、高时间分辨率的数据，帮助了解北极大气与海冰的化学关系。在这个项目中，科学团队将综合、解释 O-Buoy 网络数据并产生基本的理解。此外，GEOS-Chem 建模与 O-Buoy 测量相结合，将用于加深对北极大气与海冰之间关系的区域性了解。该项目将以多种方式促进 STEM 人力开发。 它将为早期职业科学家在其职业生涯的形成期提供支持。 它将支持三名博士的培训。学生并吸引多名本科生。 通过利用达特茅斯学院女性科学项目 (WISP) 和阿拉斯加大学阿拉斯加本土科学与工程项目 (ANSEP) 的资源，我们将努力从 STEM 领域代表性不足的群体中吸引这些学生。 将通过利用现有项目，例如 NSF 资助的下一代 WeatherBlur 项目、美国陆军工程兵团寒冷地区研究与工程实验室为新罕布什尔州中学生举办的夏季科学营、阿拉斯加大学一年一度的 Spring Science Potpourri 开放日、缅因州布斯贝港每周举办的 Café Scientifique：促进公众参与前沿科学研究的夏季系列讲座以及广泛的毕格罗海洋科学实验室的网站。 北冰洋上层大气的特点是海盐会产生活性卤素氧化剂，导致地面臭氧消耗和汞沉积。 据信这种产量是由海冰覆盖状况调节的。 该项目将回答与总体问题“北冰洋环境，特别是海冰的变化如何影响大气？”相关的三个具体科学问题。通过统计分析和建模方法。 统计方法将测试和提高对过程的理解，而建模方法将用于改进通过断裂、漂移、海冰与北冰洋的气体交换通量的量化，并预测来自海冰的活性卤素氧化剂及其前体的通量。 这些建模练习充分利用了 2009 年至 2016 年覆盖北冰洋地区的 O 浮标的数据，这一时期海冰变化很大，与历史平均水平相比，海冰有所减少。 构成该项目重点的三个具体问题是： Q1：在什么条件下，二氧化碳空气-冰-海洋通量是北冰洋大气二氧化碳变化的重要原因，相反，远距离输送何时很重要？Q2：北冰洋海冰、雪和垂直混合条件如何影响主要大气氧化剂（臭氧和活性卤素）？ Q3：海冰的年际变化和长期下降如何影响北极的大气污染物？

The Arctic region has unique atmospheric chemistry leading to both positive and negative human health impacts, such as the depletion of ground-level ozone and the deposition of mercury. Atmospheric carbon dioxide uptake into sea water, moderated by the time-varying amount of sea ice cover, causes acidification of Arctic Ocean waters with potentially important impacts on the marine ecosystem. One expects that the atmosphere and its chemistry will respond in a complex manner to sea ice change and Arctic warming, but the science community lacks the ability to make predictions with confidence given only basic mechanistic understanding of the relevant processes. The O-Buoy Chemical Network project was funded under an Arctic Observing Network grant to observe atmospheric chemicals, meteorology, and sea-ice properties that can improve our understanding of the relevant processes and thus improve predictability of scenarios of future climate. That project has deployed fifteen autonomous buoys measuring three sentinel atmospheric chemical species, each for roughly a year?s time, spread across the Arctic Ocean, providing detailed, high-time-resolution data relevant to understanding the Arctic atmosphere?s chemistry in relation to sea ice. In this project, the science team will synthesize, interpret, and generate fundamental understanding from the O-Buoy network data. In addition, GEOS-Chem modeling combined with the O-Buoy measurements will be used to develop a region wide understanding of the relationship between the Arctic atmosphere and sea ice.This project will contribute to STEM manpower development in a number of ways. It will provide support for an early career scientist during the formative years of his career. It will support the training of three Ph.D. students and engage multiple undergraduate students. Efforts will be made to draw these latter students from groups under-represented in the STEM fields by leveraging the resources of the Dartmouth College Women in Science Program (WISP) and the Alaska Native Science and Engineering Program (ANSEP) at the University of Alaska. Outreach to the K - gray community will be enabled through leveraging of existing programs such as the NSF-funded Next Generation WeatherBlur Project, the US Army Corps of Engineers' Cold Regions Research and Engineering Laboratory's summer science camp for New Hampshire middle school students, the University of Alaska's annual Spring Science Potpourri open house, the weekly Café Scientifique in Boothbay Harbor, Maine: a summer lecture series that promotes public engagement with cutting-edge scientific research, and the extensive web presence of the Bigelow Laboratory for Ocean Sciences. The Arctic Ocean's overlying atmosphere is characterized by production of reactive halogen oxidizers from sea salts that lead to depletion of ground-level ozone and deposition of mercury. This production is believed to be modulated by the state of the sea ice cover. This project will answer three specific science questions relevant to the overarching question "How do changes in the Arctic Ocean environment, especially sea ice, affect the atmosphere?" via statistical analysis and modeling approaches. Statistical methods will test and improve process understanding while modeling approaches will be used to improve quantification of gas exchange fluxes with the Arctic Ocean through the fractured, drifting, sea ice and to predict fluxes of reactive halogen oxidizers and their precursors from sea ice. These modeling exercises make full use of the data from the O-Buoys covering the Arctic Ocean region from 2009-2016+, a period which has had a great deal of sea ice variability and reduced sea ice compared to historical averages. The three specific questions constituting the foci for this project are:Q1: Under what conditions are carbon dioxide air-ice-ocean fluxes important causes of atmospheric carbon dioxide variability over the Arctic Ocean and, conversely, when is long-range transport important?Q2: How do Arctic Ocean sea ice, snow, and vertical mixing conditions affect major atmospheric oxidants (ozone and reactive halogens)?Q3: How do interannual variability and long-term declines in sea ice affect atmospheric contaminants in the Arctic?