Tutsak Ersin, Koçak Mustafa
Institute of Marine Sciences, Middle East Technical University, P.O. Box 28, 33731 Erdemli-Mersin, Turkey.
Institute of Marine Sciences, Middle East Technical University, P.O. Box 28, 33731 Erdemli-Mersin, Turkey.
Sci Total Environ. 2019 Jul 1;672:212-226. doi: 10.1016/j.scitotenv.2019.03.451. Epub 2019 Apr 1.
High time-resolved measurements of aerosol SO, NO, NH and their precursor gases HNO, SO, NH between 27 and 02 January/February and 19-01 August/September 2015 were carried out by applying AIM-IC at a rural site located on the coast of the Eastern Mediterranean, Erdemli, Turkey. The comparison between online and offline techniques revealed better correlation coefficients for SO and NH (r > 0.90) than that of NO (0.63). Mean concentrations of water-soluble species were found in decreasing order SO (2814 ng m) > NH (1371 ng m) > NO (495 ng m). NH (3390 ng m) concentration was more than enough to neutralize SO (879 ng m) and HNO (346 ng m). The gas-to-particle conversion ratios (>0.3) implied that SO, NO and NH were mainly influenced by non-local sources. SO, NO, NH, HNO, SO exhibited remarkable decrease (leastways 40%) in the atmosphere over the Eastern Mediterranean throughout fifteen years. In winter, day time NH concentrations illustrated significant relationship with temperature (positive) and humidity (negative), implying evaporation of dew or emission from plant stoma. Whereas, diurnal cycle of SO and SO was considerably influenced by populated City of Mersin in winter. During summer, HNO and SO (r = 0.74) demonstrated similar diurnal cycle, suggesting a common source for these precursor gases whilst NH was considerably affected by biomass burning emissions. Variability of all species was governed by local or nearly mesoscale transport in winter possibly due to frequent rain events. In summer, air flow from Eastern Mediterranean denoted aged air masses (GPC > 0.65) containing rather uniform concentrations of SO (65 nmol m) and NH (140 nmol m). The highest NH along with the greatest % K contribution to PM mass was observed under the influence of Northerly airflow, exhibiting significance of biomass burning emissions as a source of NH in summer.
2015年1月27日至2月2日以及8月19日至9月1日期间，通过应用AIM-IC在土耳其厄德姆利（位于东地中海沿岸的一个乡村地点）对气溶胶中的SO、NO、NH及其前体气体HNO、SO、NH进行了高时间分辨率测量。在线技术与离线技术之间的比较显示，SO和NH的相关系数（r > 0.90）比NO（0.63）更好。水溶性物种的平均浓度按降序排列为SO（2814 ng m）> NH（1371 ng m）> NO（495 ng m）。NH（3390 ng m）的浓度足以中和SO（879 ng m）和HNO（346 ng m）。气粒转化比（>0.3）表明SO、NO和NH主要受非本地源的影响。在过去十五年中，东地中海地区大气中的SO、NO、NH、HNO、SO显著下降（至少40%）。冬季，白天NH浓度与温度（正相关）和湿度（负相关）呈现显著关系，这意味着露水蒸发或植物气孔排放。然而，冬季SO和SO的日变化周期受人口密集的梅尔辛市影响很大。夏季，HNO和SO（r = 0.74）表现出相似的日变化周期，表明这些前体气体有共同来源，而NH受生物质燃烧排放影响很大。冬季所有物种的变化可能由于频繁降雨事件而受当地或近中尺度输送控制。夏季，来自东地中海的气流表示老化气团（GPC > 0.65），其中SO（约65 nmol m）和NH（约140 nmol m）浓度相当均匀。在北风气流影响下，观测到最高的NH以及对PM质量贡献最大的%K，这表明生物质燃烧排放作为夏季NH的一个来源具有重要意义。
