Nitrogen oxides and PAN in plumes from boreal fires during ARCTAS-B and their impact on ozone: an integrated analysis of aircraft and satellite observations
Nitrogen oxides and PAN in plumes from boreal fires during ARCTAS-B and their impact on ozone: an integrated analysis of aircraft and satellite observations
复制标题
DOI：
10.5194/acp-10-9739-2010
复制
发表时间：
2010-01-01
影响因子：
6.3
通讯作者：
Le Sager, P.
中科院分区：
文献类型：
--
作者：
Alvarado, M. J.;Logan, J. A.;Le Sager, P.
我们利用ARCTAS-B活动期间获得的飞机数据，确定了北方生物质燃烧产生的NOx、PAN和其他NOy物种的增强比率，并研究了这些排放物对北极对流层臭氧的影响。我们发现氮氧化物的初始排放因子为1.06 g NO / kg干物质（DM）燃烧，远低于以前对北方羽流的观测，也是温带火灾推荐值的三分之一。我们的分析首次通过观测证实了在北方烟雾中PAN的快速形成，40%的氮氧化物在排放后的最初几个小时内转化为PAN。无论是在飞机或卫星观测中，还是在模式模拟中，我们都没有发现在ARCTAS-B期间北方烟羽中形成臭氧的明确证据。美国宇航局DC8观测到的烟雾羽流中，只有三分之一显示出臭氧和一氧化碳之间的相关性，而臭氧在羽流中消耗的频率与臭氧增强的频率一样高。对流层发射光谱仪（TES）的特别观测也显示，在2008年6月15日至7月15日期间，北方烟羽中臭氧增强的证据很少。在TES观测到的22个烟雾羽中，只有4个显示烟雾羽中的臭氧增加，即使在这些情况下，也不清楚臭氧增加是由火灾排放引起的。利用GEOS-Chem大气化学模型，我们发现ARCTAS-B期间的北方火灾对加拿大上空测量到的臭氧剖面中值影响很小，对TES观测到的烟羽中的臭氧影响也很小。
We determine enhancement ratios for NOx, PAN, and other NOy species from boreal biomass burning using aircraft data obtained during the ARCTAS-B campaign and examine the impact of these emissions on tropospheric ozone in the Arctic. We find an initial emission factor for NOx of 1.06 g NO per kg dry matter (DM) burned, much lower than previous observations of boreal plumes, and also one third the value recommended for extratropical fires. Our analysis provides the first observational confirmation of rapid PAN formation in a boreal smoke plume, with 40% of the initial NOx emissions being converted to PAN in the first few hours after emission. We find little clear evidence for ozone formation in the boreal smoke plumes during ARCTAS-B in either aircraft or satellite observations, or in model simulations. Only a third of the smoke plumes observed by the NASA DC8 showed a correlation between ozone and CO, and ozone was depleted in the plumes as often as it was enhanced. Special observations from the Tropospheric Emission Spectrometer (TES) also show little evidence for enhanced ozone in boreal smoke plumes between 15 June and 15 July 2008. Of the 22 plumes observed by TES, only 4 showed ozone increasing within the smoke plumes, and even in those cases it was unclear that the increase was caused by fire emissions. Using the GEOS-Chem atmospheric chemistry model, we show that boreal fires during ARCTAS-B had little impact on the median ozone profile measured over Canada, and had little impact on ozone within the smoke plumes observed by TES.