Collaborative Research: Arctic time series measurements of atmospheric O2/N2 ratio, CO2 concentration, and CO2 isotopes in relation to changing carbon cycling and biogeochemistry

该项目支持继续通过在北极三个地点收集的烧瓶对大气二氧化碳(CO2)和氧(O2)等相关物种进行长期测量。这些测量包括几个关键大气痕量气体的最长连续地球化学记录，并与了解气候变化和北纬高纬度陆地和海洋生态系统的相关变化有直接关系。二氧化碳不仅是一种关键的温室气体，而且它的变化是陆地生态系统光合作用和呼吸作用的诊断指标，例如苔原和森林，这些生态系统支撑着北极生态系统的食物网和健康。对大气物种的相关测量，如O2和二氧化碳的同位素，补充和扩展了这一知识库。以前对大气二氧化碳的测量清楚地表明，高纬度地区的碳循环发生了戏剧性的变化。未来几十年可能会发生更大的变化，单靠模型不能帮助我们理解这些结果。因此，大气测量是观测系统的一个关键要素，它将使人们能够了解这些系统正在以多快的速度和在什么方面变化。该项目不仅继续进行长期的烧瓶测量，还通过安装在阿拉斯加乌特恰格维克的现场仪器启动新的大气测量。该项目支持在阿拉斯加的冷湾和乌特恰格维克以及埃尔斯米尔岛的警报站收集烧瓶。这些烧瓶将被送回斯克里普斯海洋研究所，在那里将对它们进行二氧化碳浓度、二氧化碳稳定同位素以及O2/N2和Ar/N2比率的分析。该项目还将支持在阿拉斯加乌特恰格维克现场安装和运行氧气/氮气分析器系统。这一新装置将能够基于解析区域来源的短期信号的能力，研究与附近楚科奇、博福特和白令海的O2交换。为了加强这些数据收集工作，该项目将支持数据分析，以检测和量化测量到的大气痕量气体的长期变化，并特别注重季节性周期的变化。此外，它还将支持在乌特恰格维克观测到的氧气变化与在最先进的数字模型中模拟的预期变化的估计之间的比较。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project supports the continuation of long-term measurements of atmospheric carbon dioxide (CO2) and related species such as oxygen (O2) via flasks collected at three Arctic sites. These measurements comprise the longest continuous geochemical records of several key atmospheric trace gases and have direct relevance for understanding climate changes and related changes in land and ocean ecosystems at high northern latitudes. CO2 not only is a critical greenhouse gas but its variations are diagnostic of photosynthesis and respiration of land ecosystems, such as tundra and forests, which support the food-web and health of Arctic ecosystems. Related measurements of atmospheric species, such as O2 and the isotopes of CO2, complement and expand this knowledge base. Previous measurements of atmospheric CO2 reveal clearly that dramatic changes have occurred in the cycling of carbon at high latitudes. Larger changes are likely to occur in the decades ahead and models alone cannot inform our understanding of those outcomes. Hence, atmospheric measurements comprise a key element of an observing system that will allow understanding of how fast and in what respect these systems are changing. This project not only continues long-term flask measurements but also initiates new atmospheric measurements through in situ instrumentation to be installed at Utqiagvik, Alaska. This project supports flask collections at Cold Bay and Utqiagvik, Alaska, and at Alert Station on Ellesmere Island. The flasks will be returned to the Scripps Institution of Oceanography where they will be analyzed for CO2 concentration, the stable isotopes of CO2, and the O2/N2 and Ar/N2 ratios. The project will also support the installation and operation of an in situ O2/N2 analyzer system at Utqiagvik, Alaska. This new installation will enable the study of O2 exchanges with the nearby Chukchi, Beaufort, and Bering Seas based on the ability to resolve short-term signals of regional origin. Augmenting these data collection efforts, this project will support data analysis to detect and quantify long-term changes in the measured atmospheric trace gases, with a particular focus on changes in seasonal cycles. In addition, it will support comparisons between the observed variations in O2 at Utqiagvik with estimates of the expected variations simulated in state-of-the art numerical models.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.