RONOCO (ROle of Nighttime chemistry in controlling the Oxidising Capacity of the AtmOsphere)

现在有越来越多的证据表明，主要由硝酸根NO3驱动的夜间化学在控制对流层的组成方面起着重要作用。最近的研究结果表明，非常高浓度的NO3存在于远离地球表面的地方。在受污染的环境中，主要的汇是丰富的，但这也是它的形成可能是最快的，因此NO3周转时间非常快。这种行为的重要性尚未得到明确理解，但它可能对大气化学和臭氧形成、区域运输和氮氧化物转化以及酸化和富营养化产生非常大的影响，还可能显著增加区域硝酸铵颗粒负担，这对气候的重要性日益增加。为了正确地理解和预测这些现象，需要量化控制NO3及其从大气中去除的基本化学过程; NO3化学对挥发性有机碳化学的影响以及作为自由基形成和传播的途径;其非均相化学及其对气溶胶负担和成分的影响;它对区域和全球范围内臭氧形成的影响，以及它对氮氧化物的大气生命周期的调节。建议开展一个联合体项目，利用仪器开发、空中测量、详细过程建模以及区域和全球建模的综合方案来解决这些相关问题。主要交付成果将是：a）增强FAAM飞机的仪器能力，包括NO3和N2 O 5的测量。B）在一系列条件下对夜间自由基、其源和汇以及边界层和自由对流层中的气溶胶成分进行全面测量。（d）控制夜间化学过程的关键过程的量化。（e）评估夜间化学对区域范围的影响。（f）评估夜间化学对当前和未来大气的全球影响。

There is now a significant and increasing body of evidence that night time chemistry, driven primarily by the nitrate radical NO3, plays a significant role in governing the composition of the troposphere. Recent findings show that very high concentrations of NO3 are present away from the Earth's surface. In polluted environments, the main sinks are abundant but this is also where its formation may be most rapid and hence the NO3 turnover time is very fast. The importance of this behaviour is not as yet clearly understood, yet it may have a very large impact on atmospheric chemistry and ozone formation, regional transport and transformation of oxidised nitrogen and hence acidification and eutrophication, and may also significantly add to the regional burden of ammonium nitrate particulate, which has increasing climatic importance. To understand and predict these phenomena correctly there is a need to quantify the basic chemical processes controlling NO3 and its removal from the atmosphere; the impact of NO3 chemistry on volatile organic carbon chemistry and as a pathway for radical formation and propagation; its heterogeneous chemistry and its impact on the aerosol burden and composition; its influence on ozone formation on regional and global scales and its mediation of the atmospheric lifecycle of oxidised nitrogen. A consortium project is proposed that addresses these coupled questions using a combined programme of instrument development, airborne measurement, detailed process modelling, and regional and global modelling. The principal deliverables will be: a) Enhancements to the instrumental capability of the FAAM aircraft to include measurements of NO3 and N2O5. b) Comprehensive measurements of night time radicals, their sources and sinks, and aerosol composition in the boundary layer and free troposphere in a range of conditions. d) Quantification of the key processes which control night-time chemical processes. e) Assessment of the impacts of night-time chemistry on regional scales. f) An assessment of the global impacts of night-time chemistry in the current and future atmospheres.