Novel High-resolution Trace Gas Retrievals from Aircraft in Support of Regional Air Quality Modelling

该研究金的目的是通过航空红外光谱仪提供高空间分辨率的污染物痕量气体浓度的新的同步测量，以支持区域空气质量模拟。城市地区糟糕的空气质量和城市羽流的顺风向已被证明对人体健康有害，由于长期暴露在城市背景污染水平和短期暴露在热浪等急性时段的污染物水平大幅上升，预期寿命缩短。那些既往患有呼吸系统或心血管疾病的人最有可能经历生活质量下降。世界卫生组织报告称，空气中的颗粒物(也称为气溶胶)、臭氧和二氧化氮气体是这种健康影响的最大贡献者。气候变化进一步加剧了这种对健康的影响--政府间气候变化专门委员会(IPCC)表示，臭氧和二氧化氮的对流层浓度预计将随着气温的上升而增加。2003年8月西欧的热浪事件就突出了这一点，整个欧洲有超过44000人额外死亡，其中许多人是由于热应激，但也有许多人是由于与上文讨论的痕量气体浓度升高有关的急性呼吸问题。尽管这是公共健康的一个重要方面，但导致产生对健康造成影响的主要污染物的大气过程仍然知之甚少。为了制定一项应对空气质量差问题的战略，首先需要在城市规模和由此产生的羽流中了解这种过程。在高空间分辨率下同时测量多种大气污染物浓度是城市和区域空气质量模型准确性的关键，这些模型使用这些浓度作为输入。目前，通常使用的排放清单和低空间分辨率数据集，如卫星遥感仪器目前提供的数据集，无法满足这一需要。该研究金的目标是通过为一系列与区域空气质量模拟相关的污染物痕量气体提供新颖的高分辨率痕量气体测量来满足这一重要的测量需求，例如二氧化氮、臭氧及其储存库。这些数据将同时并首次从BAE-146飞机上的NERC机载大气测量设备上的机载研究干涉仪评估系统(ARIES)记录的大气红外光谱中记录下来。为了实现这一点，该研究员将使用为白羊座开发的提取测量技术作为该奖学金的一部分。与英国气象局合作，将在伦敦城市污染羽流上空和内部进行一系列BAE-146飞机调查(20个飞行小时)，以测量城市顺风向的污染物浓度。然后，新的痕量气体数据将与正在进行的伦敦清洁空气(ClearfLo)测量和建模研究中产生的空气质量模型输出进行定量比较，该研究旨在描述导致有害空气质量事件的过程。比较研究的结果将用于通过了解羽流模型及其输入中的偏差来源来改进ClearFlo羽流模型。作为该研究金的一部分，飞机测量将与2012年夏季和冬季作为ClearFlo的一部分在伦敦进行密集地面测量的时间相协调。这一新的高测量能力将为长期数据集铺平道路，以支持区域和全球空气质量建模工作，卫星红外遥感的未来进展可能为同步研究提供协同的大规模但较低分辨率的痕量气体浓度数据。

The aim of this fellowship is to provide novel and simultaneous measurements of pollutant trace gas concentrations at high spatial resolution from an airborne infrared spectrometer in support of regional air quality modeling. Poor air quality in urban areas and those downwind of urban plumes has been shown to be detrimental to human health, with reduced life expectancy due to both long-term exposure at background urban pollution levels and short-term exposure to dramatically elevated pollutant levels in acute episodes such as heat waves for example. Those with pre-existing respiratory or cardiovascular disease are most at risk of experiencing a reduced quality of life. The World Health Organisation has reported that airborne particulate matter (also known as aerosol), ozone and nitrogen dioxide gas are the strongest contributors to such health impacts. Such health impacts are further exacerbated by climate change - the Intergovernmental Panel on Climate Change (IPCC) suggests that tropospheric concentrations of ozone and nitrogen dioxide are expected to increase with rising temperature. This is highlighted by the well-documented heat wave event of Western Europe in August 2003, which saw more than 44000 excess deaths across Europe, many due to heat stress but many also due to acute respiratory problems linked to elevated concentrations of the trace gases discussed above. Despite this important aspect of public health, the atmospheric processes leading to the production of the key pollutants responsible for health impacts remains poorly understood. To develop a strategy for dealing with the problem of poor air quality, such processes need to first be understood both at the city scale and within resulting plumes. Simultaneous measurement of many atmospheric pollutant concentrations at high spatial resolution is key to the accuracy of urban and regional air quality models, which use such concentrations as inputs. This need is currently not met by commonly used emissions inventories and low spatial resolution datasets, such as those currently offered by satellite remote sensing instruments. The ambition of this Fellowship is to meet this important measurement need by providing novel high resolution trace gas measurements for a range of pollutant trace gases pertinent to regional air quality modelling such as nitrogen dioxide, ozone and their reservoirs. Such data will be recorded simultaneously and for the first time from infrared spectra of the atmosphere recorded by the Airborne Research Interferometer Evaluation System (ARIES) instrument onboard the NERC Facility for Airborne Atmospheric Measurement (FAAM) BAe-146 aircraft. To achieve this, the Fellow will use retrieval measurement techniques developed for ARIES as part of this fellowship. In partnership with the UK Met Office, a series of BAe-146 aircraft surveys (20 flying hours) will be conducted over and within the London urban pollution plume to measure pollutant concentrations downwind of the city. The new trace gas data will then be quantitatively compared to air quality model output generated as part of the ongoing Clean Air for London (ClearfLo) measurement and modelling study, which aims to characterise the processes leading to harmful air quality episodes. The results of the comparative study will be used to improve the ClearFlo plume model by understanding sources of bias in the plume model and its inputs. The aircraft surveys proposes as part of this Fellowship will be coordinated to coincide with periods of intensive ground measurement in London as part of ClearFlo in both Summer and Winter 2012. This new high-measurement capability will pave the way for a long-term dataset to support regional and global air quality modeling efforts, with future advances in satellite infrared remote sensing likely to provide synergistic large-scale but lower resolution trace gas concentration data for synchronized studies.