Collaborative Research: EAGER--Novel Sampling and Isotopic Characterization of Upper Strato- to Mesospheric Photochemistry

合作研究：EAGER——上平层至中层光化学的新型采样和同位素表征

• 批准号: 2204475
• 负责人: David Johnston
• 金额: $ 3.61万
• 依托单位: Harvard University
• 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: 2022-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204475&HistoricalAwards=false
• 关键词: Collaborative; Research; EAGER; Novel; Sampling

Isotopes in the atmosphere, such as 17O, 18O and others, can be used as tracers to track the movement of the atmosphere and understand the chemical reactions producing them. Obtaining measurements of such isotopes is difficult in the mesosphere which is too high to be reached by balloons. This project will experiment with a novel rocket technology to obtain air samples in the mesosphere and use state of the art mass spectrometers to analyze isotopes in the samples.The team plans to deploy a novel, zero-carbon emission rocket that will enable atmospheric sample collection at 37 km and 70 km altitude in the atmosphere. This will provide proof-of-concept for a clean, inexpensive, and efficient rocket sampler capable of atmospheric exploration well beyond the current altitude limit of conventional balloons (30 km). This rocket technology and platform will facilitate direct sampling of the upper atmosphere, especially the mesosphere on a scale that is currently economically and environmentally infeasible. Four atmospheric samples (2 launches at 37 km, 2 at 70 km) will be isotopically characterized using state of the art mass spectrometers at both UCSD and Harvard. The target atmospheric gasses are O2, CO2 and N2, which have either never been, or are severely under-sampled at these altitudes, limiting our understanding of mesospheric contributions to the stratosphere and troposphere. Isotopic analyses will also extend to the trace oxygen isotope – 17O – and isotopic ‘clumping’ in both O2 and CO2. The measurements will be compared to new laboratory experiments on the CO2-O2-O3 photochemical system, which aim to better constrain the characteristic isotope effects and physical chemistry of Mesosphere/Stratosphere O3 photolysis. This new rocket borne sampling technology is more flexible in terms of altitude targets, cheap relative to other sampling platforms, and environmentally responsible. It will open up new opportunities for sampling the atmosphere, most notably the mesosphere, and enable direct insight into atmospheric photochemistry, specially that related to ozone cycle, and better insight into this chemistry in situ and as it relates to airmasses being delivered to the strato- and troposphereThis 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.

大气中的同位素，如 17O、18O 等，可用作示踪剂来追踪大气的运动并了解产生这些同位素的化学反应，而在中间层测量这些同位素是很困难的，因为中间层太高而无法到达。该项目将尝试一种新颖的火箭技术来获取中间层的空气样本，并使用最先进的质谱仪来分析样本中的同位素。该团队计划部署一个新型零碳排放火箭将能够在大气层 37 公里和 70 公里高度采集大气样本，这将为清洁、廉价且高效的火箭采样器提供概念验证，其能够进行远远超出当前水平的大气探索。该火箭技术和平台将有助于对高层大气进行直接采样，特别是在目前经济和环境上不可行的规模上进行采样。 四个大气样本（2个在37公里处发射，2个在37公里处发射）。 70 公里）将使用加州大学圣地亚哥分校和哈佛大学最先进的质谱仪进行同位素表征，目标大气气体是 O2、CO2 和 N2，这些气体要么从未在这些高度进行过采样，要么严重不足，限制了我们的理解。中层对平流层和对流层的贡献的同位素分析也将扩展到痕量氧同位素 - 17O - 和 O2 中的同位素“聚集”。测量结果将与 CO2-O2-O3 光化学系统的新实验室实验进行比较，旨在更好地限制中间层/平流层 O3 光解的特征同位素效应和物理化学。这种新的火箭运载采样技术更加灵活。就高度目标而言，相对于其他采样平台便宜且对环境负责，它将为大气（尤其是中间层）采样提供新的机会，并能够直接了解大气光化学，特别是与臭氧相关的光化学。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。