Multi-site Synthesis of the Role of Canopy Processes and Emissions on Ozone and Secondary Organic Aerosols

生物源挥发性有机化合物(BVOC)的排放，如陆地植被的排放，通过以下方式对对流层的组成和大气的氧化能力起到重要的控制作用：(1)它们在活性氮氧化物(NOx=NO+NO2)和阳光存在下形成臭氧，(2)氢氧自由基(HOx=OH+HO2)的调节和(3)通过BVOC氧化产物的转化形成二次有机气溶胶(SOA)。森林地区的野外运动继续提高我们对BVOC排放对气相对流层化学作用的理解。然而，关于它们在HOX化学和SOA形成中的详细作用，仍然存在很大的不确定性。需要多点合成来提高对解释BVOC反应性所需的关键物理和化学过程的理解。密歇根大学和华盛顿州的研究人员使用一个计算高效的一维(1D)模型，最终目标是改善BVOCs的区域和全球尺度表示，他们假设，最近为热带森林开发的许多HOX机制变化不会在中纬度实现预期的模型改进。来自大约五个美国战役的观察结果将以综合的方式进行综合，这种综合集成有望澄清森林在对流层化学中的作用，这些区域位于中等清洁到污染的地区，如美国大陆。由于BVOC也是臭氧和大气气溶胶等短期气候强迫因素的重要前体，因此在未来的气候模型中也需要改进这些物种的代表性。

The emissions of biogenic volatile organic compounds (BVOCs), such as those from terrestrial vegetation, are known to exert significant control on tropospheric composition and the oxidation capacity of the atmosphere through:(1) their formation of ozone in the presence of reactive nitrogen oxides (NOx = NO + NO2) and sunlight, (2) the regulation of hydrogen oxide radicals (HOx = OH + HO2) and(3) the formation of secondary organic aerosols (SOA) through the transformation of BVOC oxidation products Field campaigns in forested regions continue to improve our understanding of the role of BVOC emissions on gas-phase tropospheric chemistry, yet large uncertainties remain regarding their detailed role in HOx chemistry and SOA formation. A multi-site synthesis is needed to improve understanding of the key physical and chemical processes needed to account for BVOC reactivity. Using a computationally efficient one-dimensional (1D) model, with the ultimate goal of improving regional- and global-scale representation of of BVOCs, researchers from University of Michigan and Washington State hypothesize that many of the HOx mechanism changes recently developed for tropical forests will not achieve the desired model improvement at mid-latitudes. Observations from some five individual US campaigns are to be synthesized in a comprehensive manner and this meta-synthesis is hoped to clarify the role of forests on tropospheric chemistry in moderately clean to polluted regions such as found in the continental US. Since BVOC are also important precursors for short-lived climate forcing agents such a ozone and atmospheric aerosols, improved representation of these species is also needed in future climate models.