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

该项目的目标包括更好地理解中国上空对流层臭氧及其前体(特别是NOx、氮氧化物、NO+NO2)丰度和季节变化的调节因素。将利用空间对二氧化氮的多年观测，以改进中国上空氮氧化物燃烧和生物源的季节和空间变化的信息。利用中国北部一个地面站首次连续、长期、同时测量二氧化碳和二氧化碳，将制定与中国化石燃料消耗相关的CO和二氧化碳(一氧化碳和二氧化碳)排放的新限制条件。在理解排放方面的改进将被纳入三维嵌套网格化学模式(GEOS-Chem)，以分析亚洲上空不同季节的臭氧地面和飞机观测。这项工作的具体目标是：(1)根据对来自国家气象局和其他卫星仪器的NO2柱的多年观测数据的重新分析，得出对中国上空NOx燃烧和微生物源季节性变化的“自上而下”估计；(2)利用三维嵌套网格模式分析飞机和一年的地面观测记录，确定导致对流层臭氧季节变化和亚洲大陆臭氧流出的因素；(3)提高对与中国化石燃料消耗有关的二氧化碳排放的认识，以及生物圈对中国上空二氧化碳区域预算的作用。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来源的了解。这将有助于政策制定者了解臭氧污染对中国公共健康和农业生产力的复杂影响。这项工作的成果也将融入哈佛大学本科生(理科和非理科)和研究生的教学中。

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.