Center for Air Resource Engineering and Science, Clarkson University, Potsdam, New York 13699-5708, USA.
Environ Sci Technol. 2010 Nov 15;44(22):8435-40. doi: 10.1021/es1024806. Epub 2010 Oct 27.
The impact of Canadian forest fires in Quebec on May 31, 2010 on PM(2.5), carbonaceous species, and atmospheric mercury species was observed at three rural sites in northern New York. The results were compared with previous studies during a 2002 Quebec forest fire episode. MODIS satellite images showed transport of forest fire smoke from southern Quebec, Canada to northern New York on May 31, 2010. Back-trajectories were consistent with this regional transport. During the forest fire event, as much as an 18-fold increase in PM(2.5) concentration was observed. The concentrations of episode-related OC, EC, BC, UVBC, and their difference (Delta-C), reactive gaseous mercury (RGM), and particle-bound mercury (PBM) were also significantly higher than those under normal conditions, suggesting a high impact of Canadian forest fire emissions on air quality in northern New York. PBM, RGM, and Delta-C are all emitted from forest fires. The correlation coefficient between Delta-C and other carbonaceous species may serve as an indicator of forest fire smoke. Given the marked changes in PBM, it may serve as a more useful tracer of forest fires over distances of several hundred kilometers relative to GEM. However, the Delta-C concentration changes are more readily measured.
2010 年 5 月 31 日,加拿大魁北克森林大火对纽约北部三个农村地区的 PM(2.5)、含碳物种和大气汞物种的影响已被观察到。这些结果与 2002 年魁北克森林火灾期间的先前研究进行了比较。MODIS 卫星图像显示,5 月 31 日,来自加拿大魁北克南部的森林火灾烟雾被输送到纽约北部。后向轨迹与这种区域输送一致。在森林火灾事件期间,PM(2.5)浓度增加了 18 倍。与该事件相关的 OC、EC、BC、UVBC 及其差值(Delta-C)、反应性气态汞(RGM)和颗粒结合汞(PBM)的浓度也明显高于正常条件下的浓度,这表明加拿大森林火灾排放物对纽约北部空气质量的影响很大。PBM、RGM 和 Delta-C 均来自森林火灾。Delta-C 与其他含碳物种之间的相关系数可用作森林烟雾的指标。鉴于 PBM 的明显变化,与 GEM 相比,它可能是几百公里范围内森林火灾更有用的示踪剂。然而,Delta-C 浓度变化更容易测量。