Dry deposition processes of volatile organic compounds (VOCDep)

挥发性有机化合物的干沉积工艺 (VOCDep)

• 批准号: NE/V012908/1
• 负责人: Eloise Ann Marais
• 金额: $ 15.87万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FV012908%2F1
• 关键词: Dry; deposition; processes; volatile; organic

A large range of different volatile organic chemical compounds (VOCs) are released to the atmosphere from vegetation and human activities such as fossil fuel burning and the use of consumer care products. Together with nitrogen oxides, VOCs are one of the two key ingredients for the formation of tropospheric ground-level ozone pollution, causing impacts on human health, biodiversity decline and crop losses. Similarly, through a series of chemical reactions in the atmosphere, many VOCs end up forming the organic fraction of particulate matter (PM) with major impacts on human health around the globe. VOC emissions are needed in models to predict air quality and its impacts and climate change. These models are used to assess measures to reduce emissions to safeguard the health of humans and the environment. For these model predictions to be reliable, the models need to accurately represent VOC emissions, chemical transformation, but also the deposition to vegetation. Whilst considerable effort has gone into the first two aspects, very little is known about the deposition of the various VOC compounds, with deposition rates usually estimated from the behaviour of other (inorganic) compounds with no validation through actual measurements.This project will make use of recent improvements in VOC measurement technology to perform the first comprehensive study of the rate and processes that control the deposition of a wide range of different VOC compounds of environmental concern. This will be achieved through three different, complementary experimental approaches: (a) the study of VOC uptake to vegetation in the laboratory using gas exchange chambers, (b) the study of VOC uptake to natural and artificial liquid water films and (c) two measurement campaigns of VOC exchange with vegetation, focussing on urban parkland and forest. The results from these measurements and existing datasets from project partners will be used to derive improved model descriptions of the deposition process for incorporation into the numerical models. We will then use two atmospheric chemistry and transport models, a simpler model that can be operated at high spatial resolution and is used to support European and UK policy, and a model with a more detailed description of the chemistry of isoprene, the compound that dominates plant emissions globally to assess the impacts of the new deposition rates on model performance with emphasis on ozone formation, PM formation and the particular role of isoprene in PM formation.

大量不同的挥发性有机化合物(VOCs)从植被和人类活动中释放到大气中，如燃烧化石燃料和使用消费者护理产品。与氮氧化物一样，VOCs是形成对流层地面臭氧污染的两个关键成分之一，对人类健康、生物多样性下降和作物损失造成影响。同样，通过大气中的一系列化学反应，许多VOCs最终形成颗粒物(PM)的有机部分，对全球人类健康产生重大影响。要预测空气质量及其影响和气候变化，需要在模型中使用VOC排放。这些模型用于评估为保护人类健康和环境而采取的减排措施。为了使这些模型的预测可靠，这些模型需要准确地表示VOC排放、化学转化以及向植被的沉积。虽然在前两个方面已经做出了相当大的努力，但人们对各种VOC化合物的沉积知之甚少，沉积速率通常是根据其他(无机)化合物的行为估计的，没有通过实际测量进行验证。该项目将利用VOC测量技术最近的改进，对控制各种不同VOC化合物沉积的速率和过程进行第一次全面的研究。这将通过三种不同的、互补的实验方法来实现：(A)利用气体交换室在实验室中研究植物对VOC的吸收，(B)研究VOC对天然和人造液态水薄膜的吸收，以及(C)以城市公园和森林为重点的两次VOC与植被交换的测量活动。这些测量的结果和项目伙伴提供的现有数据集将用于推导沉积过程的改进模型描述，以便纳入数值模型。然后，我们将使用两个大气化学和输送模型，一个更简单的模型，可以在高空间分辨率下操作，用于支持欧洲和英国的政策，以及一个更详细地描述异戊二烯化学的模型，异戊二烯是全球工厂排放的主要化合物，以评估新沉积速率对模型性能的影响，重点是臭氧形成、PM形成和异戊二烯在PM形成中的特殊作用。