Theoretical Studies of the Chemical Composition of the Earth's Atmosphere

这项研究项目旨在解决平流层和对流层化学中的关键问题。对于平流层，(1)将利用实地观测来测试和完善我们对不均匀过程对低平流层化学作用的理解；(2)将开发并应用诊断模型来阐明造成臭氧长期趋势的化学和动力学机制，并特别注意火山气溶胶的全球影响；(3)将审查反硝化作用的作用，将其作为对极地地区臭氧损失的控制影响，作为澄清北极和南极臭氧损失之间差异的战略的一部分。对于对流层，PI建议：(1)最近实地考察的短期物种数据将用于测试和改进光化学机制；(2)测试全球三维化学示踪模型(CTM)中的羟基分布将使用碳14标记的一氧化碳的观测；(3)CTM将用于测试一氧化碳的来源清单，这是调节羟基自由基浓度的关键物种，利用关于碳13标记的一氧化碳和碳18标记的一氧化碳的新数据，并包括对乙烯和乙炔的额外研究。(4)CTM还将用于调查从1950年到现在对流层氧化力的变化。

ATM-9320778 McElroy This research project is aimed at addressing key issues in stratospheric and tropospheric chemistry. For the stratosphere, (1) field observations will be used to test and refine our understanding of the role of heterogenous processes on the chemistry of the lower stratosphere; (2) diagnostic models will be developed and applied to elucidate the chemical and dynamical mechanisms responsible for long-term trends in the ozone, with particular attention to global effects of volcanic aerosols; and (3) the role of denitrification will be examined as the controlling influence on loss of ozone in polar regions, as part of a strategy to clarify differences between ozone loss in the Arctic and Antarctic. For the troposphere, the PI proposes to: (1) data for short-lived species from recent field expeditions will be used to test and improve photochemical mechanisms; (2) to test the distribution of hydroxyl radical in a global three-dimensional Chemical Tracer Model (CTM) will be tested using observations of carbon 14 labeled carbon monoxide; (3) the CTM will be used to test inventory of sources for carbon monoxide, a key species regulating hydroxyl radical concentrations, taking advantage of new data for carbon 13 labeled carbon monoxide and carbon 18 labeled carbon monoxide and including additional studies of ethylene and acetylene and (4) the CTM will also be used to investigate changes in the oxidizing power of the troposphere from 1950 to the present.