Collaborative Research: SNOWpack Photodenitrification from the Antarctic and Arctic Cryosphere (SNOWPAAC)

合作研究：南极和北极冰冻圈的 SNOWpack 光脱氮 (SNOWPAAC)

• 批准号: 1244817
• 负责人: Becky Alexander
• 金额: $ 14.05万
• 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: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1244817&HistoricalAwards=false
• 关键词: Collaborative; Research; SNOWpack; Photodenitrification; Antarctic

The importance of knowing the different sources of atmospheric nitrate to the polar ice sheets of Antarctica and Greenland, along with their transport paths, is of intrinsic interest to the atmospheric chemistry of polar NOx species. In turn, surface photolysis of snowpack nitrate renders these ice sheets as strongly oxidizing surfaces during sunlight. Attempts to derive past conditions or variability of atmospheric NOx (= NO + NO2 +?) species from ice core records will need to take photodenitrification and source transfer function effects into account. The approach willcontinue to use a inverse chemical transfer model (adjoint GEOS-Chem) to test the sensitivity of nitrate deposition to the Antarctic continent from various possible sources. The following questions are posed: 1) what are the important sources of nitrate to Antarctia (and Greenland) in the present and in the pre-industrial Holocene? 2) How does the recycling of reactive nitrogen at the atmosphere-snow interface redistribute nitrate across large polar ice sheets? and 3) are their implications for nitrate preservation in ice cores and their interpretation?Goals being pursued in this modeling study include the reconstruction of past (polar) atmospheric composition and a better contemporary understanding of the variability of atmospheric reactive nitrogen compounds as may be discerned from measurements of nitrate concentrations retained in snow, firn and possibly ice cores in polar regions.

了解南极和格陵兰的极性冰面的不同大气来源以及它们的运输路径的重要性是极性NOX物种大气化学的内在兴趣。反过来，积雪硝酸盐的表面光解会使这些冰片在阳光下具有强烈的氧化表面。 尝试从冰核记录中得出过去的条件或大气NOx（= no + no2 +？）物种的变异性的尝试将需要考虑光硝化和源传递函数效应。 该方法将使用反向化学转移模型（伴随地理化学）来测试硝酸盐沉积对南极大陆的敏感性，从各种可能的来源。提出以下问题：1）目前和工业前全新世中硝酸盐（和格陵兰）的硝酸盐（和格陵兰）的重要来源是什么？ 2）如何在大气中的鼻界面上的反应性氮在大型极性冰盖上重新分布硝酸盐？ and 3) are their implications for nitrate preservation in ice cores and their interpretation?Goals being pursued in this modeling study include the reconstruction of past (polar) atmospheric composition and a better contemporary understanding of the variability of atmospheric reactive nitrogen compounds as may be discerned from measurements of nitrate concentrations retained in snow, firn and possibly ice cores in polar regions.