The Abundance and Seasonal Variability of Tropospheric Ozone and Its Precursors Over China

该项目的目标包括更好地了解中国上空对流层臭氧及其前体（特别是NOx、氮氧化物、NO + NO2）的丰度和季节变化的调节因素。 将利用从空间对NO2的多年观测来改进关于中国上空燃烧和生物来源的NOx的季节和空间变化的信息。 将利用中国北方地面站首次连续、长期、同时测量的CO2和CO，制定与中国化石燃料消费相关的CO和CO2（一氧化碳和二氧化碳）排放的新限制。 将把对排放的进一步了解纳入一个三维嵌套网格化学模式（GEOS-Chem），以分析亚洲不同季节的地面和飞机臭氧观测结果。 具体目标是：（1）根据GOME等卫星仪器对NO2柱的多年观测资料进行再分析，“自上而下”地估算中国上空NOx的燃烧和微生物来源的季节变化;（2）利用三维嵌套模式确定对流层臭氧季节变化和亚洲大陆臭氧外流的影响因素，网格模型来分析飞机和地面观测的一年之久的记录;和（3）提高对与中国化石燃料消耗相关的CO2排放和生物圈在中国区域CO2收支中的作用的理解。 这项研究有望提高我们对全球范围内NOx燃烧和生物来源的理解，特别是对快速发展的中国的NOx来源的理解。 这将有助于决策者了解臭氧污染对中国公众健康和农业生产力的复杂影响。 这项工作的结果也将被纳入本科（科学和非科学）和研究生在哈佛的教学。

The goals of this project include an improved understanding of factors regulating the abundance and seasonal variability of tropospheric ozone and its precursors (in particular NOx, nitrogen oxides, NO + NO2) over China. Multi-year observations of NO2 from space will be employed to develop improved information on seasonal and spatial variations in combustion and biological sources of NOx over China. New constraints on emissions of CO and CO2 (carbon monoxide and dioxide) associated with Chinese fossil fuel consumption will be developed using the first continuous, long-term, simultaneous measurements of CO2 and CO at a surface station in north China. Improvements in understanding of emissions will be incorporated in a 3-dimensional nested grid chemical model (GEOS-Chem) to analyze surface and aircraft observations of ozone for different seasons over Asia. Specific objectives of the work are: (1) to develop 'top-down' estimates for the seasonal variation of combustion and microbial sources of NOx over China based on a reanalysis of multi-year observations of NO2 columns inferred from GOME and other satellite instruments; (2) to determine factors responsible for the seasonal variability of tropospheric ozone and the outflow of ozone from the Asian landmass using a 3-D nested-grid model to analyze aircraft and a year long record of surface observations; and (3) to improve the understanding of emissions of CO2 associated with Chinese fossil fuel consumption and the role of the biosphere for the regional budget of CO2 over China. This research is expected to improve our understanding of combustion and biological sources of NOx on a global scale with particular emphasis on sources from rapidly developing China. This will be helpful for policy makers by providing input into understanding the complex impacts of ozone pollution on public health and agricultural productivity in China. Results of this work will also be integrated into the teaching of undergraduate (science and non-science) and graduate students at Harvard.