Investigating Source, Chemistry and Climate changes using the Isotopic Composition of Nitrate in Antarctic Snow and Ice

Hastings/1246223该奖项支持一个项目，其目的是利用档案雪和冰样本中的雪的同位素比率来区分南极西部冰盖（WAIS）的硝酸盐沉积来源。硝酸盐的同位素组成已被证明包含有关硝酸盐来源的信息（即氮氧化物= NOx = NO + NO2）和在沉积之前将NOx转化为大气中的硝酸盐的氧化过程。在氮氧化物来源的背景下解释记录的一个困难是，硝酸盐可以在地表雪中进行沉积后处理，这样存档的记录就不能反映大气的组成。这项工作的智力价值，特别是旨在调查的变化，硝酸盐的同位素组成的雪和冰从WAIS的积累率，氮氧化物源的排放量和大气化学的背景下。这些记录将在我们对生物圈（生物质燃烧，土壤中的微生物过程），大气（闪电，运输，化学）和气候（温度，累积率）随时间变化的理解的背景下进行解释。一名研究生将作为本项目的一部分得到支持，研究生和PI都将参与向国际扶轮地区普罗维登斯的小学生传达极地研究的效用和结果。该项目的更广泛影响还包括通过建立PI Hastings帮助建立的组织地球科学女性网络（ESWN）和极地早期职业科学家协会（APECS）之间的联系，努力吸引更多年轻的女性科学家进行极地研究。最后，所有测量的结果将在相关会议上介绍，公开提供并发表在同行评审的期刊上。

Hastings/1246223 This award supports a project with the aim of distinguishing the sources of nitrate deposition to the West Antarctic Ice Sheet (WAIS) using isotopic ratios snow in archive snow and ice samples. The isotopic composition of nitrate has been shown to contain information about the source of the nitrate (i.e. nitrogen oxides = NOx = NO+NO2) and the oxidation processes that convert NOx to nitrate in the atmosphere prior to deposition. A difficulty in interpreting records in the context of NOx sources is that nitrate can be post-depositionally processed in surface snow, such that the archived record does not reflect the composition of the atmosphere. This intellectual merit of this work specifically aims to investigate variability in the isotopic composition of nitrate in snow and ice from the WAIS in the context of accumulation rate, NOx source emissions, and atmospheric chemistry. These records will be interpreted in the context of our understanding of biospheric (biomass burning, microbial processes in soils), atmospheric (lightning, transport, chemistry), and climate (temperature, accumulation rate) changes over time. A graduate student will be supported as part of this project, and both graduate student and PI will be involved in communicating the utility and results of polar research to elementary school students in the Providence, RI area. The broader impacts of the project also include making efforts to attract more young, female scientists to polar research by establishing a connection between the Earth Science Women's Network (ESWN), an organization PI Hastings helped to establish, and the Association of Polar Early Career Scientists (APECS). Finally, results of all measurements will be presented at relevant conferences, made available publicly and published in peer-reviewed journals.