An Integrated Study of Air Pollutant Sources in the Delhi National Capital Region (NCR)

2014年，德里被世界卫生组织评为世界上环境空气污染最严重的城市。大约有4600万人居住在德里及其周边地区-其中1800万人居住在城市，其余的人居住在周围的国家首都地区（NCR）。颗粒物（PM）是德里最重要的空气污染物，2014年的年平均水平超过了世卫组织指南的15倍，对慢性和急性健康影响非常大，并伴随着经济成本。制定改善空气质量的有效战略需要对空气中颗粒物的来源、形成过程、区域预算以及化学和物理性质有定量的了解;然而，目前还没有这种知识。ASAP德里解决了这一要求：该项目将提供一个定量评估的来源，特点，丰富和形成过程中的PM在德里和周围的NCR。该项目旨在解决关键的科学问题（见下文），其理念是通过高质量的直接观察，即基于对德里地面空气中实际存在的物种的测量，而不依赖于其他数据，深入了解污染物来源和预算。该项目代表了来自英国的领先研究人员之间的重点合作（伯明翰，萨里郡）和印度（IITD，NPL），他们有成功的联合合作和出版物的跟踪记录，从以前资助的空气质量项目在德里。ASAP德里将（i）进行最详细的物理和化学表征目前在德里，并在周围的国家首都地区（NCR）的日期;（二）编制污染源概况（化学特征）的主要PM来源在德里;（iii）确定和量化不同来源对德里PM负担的贡献（和NCR）-对于PM质量浓度和颗粒数量[对健康有不同影响]，通过应用多种独立的、已建立的和新的受体建模方法，如化学质量平衡，放射性碳和基于数粒分布的源解析;（iv）估计NCR排放对德里空气质量的影响（有效的区域空气质量政策的关键）和（v）评估一系列在污染事件期间形成PM的新假设，这对于准确预测未来PM水平的模型至关重要。我们将通过一系列实地观察来实现这些目标，将在线测量与最先进的离线分析相结合，在德里（城市背景位置-全年采样与两个“密集”相结合），周围的NCR（五个地点的季节性测量）和农村背景位置（逆风150公里）。我们的测量策略结合了（i）已建立的方法-提供高质量，系统，连贯的测量数据集，具有新颖的空间分布-和（ii）新的科学工具和分析方法。这提供了国际质量观测（支持ASAP德里和其他计划组成部分）和新指标之间的平衡，同时也认识到在这种环境中实地工作的现实。ASAP-Delhi将利用APHH印度计划中其他项目的成果，并将提供关键的观测见解，以支持空气质量模型开发，人类健康影响评估以及更广泛计划中缓解政策的制定。在解决公共卫生，政策和发展问题，并提供一个平台，以加强印度的空气污染研究，ASAP德里解决了官方发展援助的支持类别（i）人和（ii）研究计划，除了提供一个步骤的变化，在德里PM的来源的理解（决策者需要的关键见解）。

Delhi was rated the most polluted city in the world for ambient air pollution by the WHO in 2014. Some 46 million people live in and around Delhi - 18m in the city, and the remainder in the surrounding National Capital Region (NCR). Annual mean levels of particulate matter (PM), the most important air pollutant for health in Delhi, exceeded WHO guidelines by a factor of 15 during 2014, and are responsible for very substantial chronic and acute health impacts, with attendant economic costs. Development of effective strategies for improvement in air quality requires quantitative understanding of the sources, formation processes, regional budgets and chemical and physical nature of airborne particulate matter; however, such knowledge is not yet available. ASAP-Delhi addresses this requirement: The project will provide a quantitative assessment of the sources, characteristics, abundance and formation processes for PM in Delhi and the surrounding NCR. The project is designed to address key science questions (below), with a philosophy of obtaining insights into pollutant sources and budgets from high quality direct observation - i.e. based upon measurement of the species actually present in the air at ground level within Delhi, without dependence upon other data. The project represents a focussed collaboration between leading researchers from the UK (Birmingham, Surrey) and India (IITD, NPL), who have a track record of successful joint collaboration and publications from previous funded air quality projects in Delhi.ASAP-Delhi will (i) perform the most detailed physical and chemical characterisation of PM present in Delhi, and in the surrounding National Capital Region (NCR) to date; (ii) produce source profiles (chemical signatures) for the principal PM sources in Delhi; (iii) identify and quantify the contributions of different sources to the PM burden in Delhi (and the NCR) - for both PM mass concentration and particle number [with differing implications for health], by application of multiple, independent, established and novel receptor modelling approaches, such as chemical mass balance, radiocarbon, and number size distribution based source apportionment; (iv) estimate the impact of NCR emissions upon air quality in Delhi (key to effective regional air quality policy) and (v) evaluate a series of new hypotheses for the formation of PM during pollution episodes, essential for accurate model predictions of future PM levels.We will address these objectives through a series of field observations, combining online measurements with state-of-the-science offline analyses, in Delhi (urban background locations - year round sampling combined with two "intensives"), the surrounding NCR (seasonal measurements at five sites) and a rural background location (150 km upwind). Our measurement strategy combines (i) established methodologies - to deliver a high quality, systematic, coherent measurement dataset, with a novel spatial distribution - and (ii) new state-of-the-science tools and analytical approaches. This provides a balance between international quality observations (in support of ASAP-Delhi and other programme components) and novel metrics, whilst also recognising the realities of fieldwork in such environments. ASAP-Delhi will draw upon results of other projects in the APHH India programme, and will provide the key observational insights in support of air quality model development, evaluation of human health impacts, and development of mitigation policies in the wider programme. In addressing public health, policy and development issues, and providing a platform to enhance air pollution research in India, ASAP-Delhi addresses the ODA support categories of (i) people and (ii) research programmes, in addition to providing a step-change in understanding of the sources of PM in Delhi (the key insight required by policymakers).