Seasonal variations of the near-surface NO_X (= NO + NO₂) and ozone (O₃) mixing ratios at Zotino Tall Tower (ZOTTO), a remote site in central Siberia, are described for years 2007–2014. Conditional probability function analysis and back trajectories are used to determine the origins of clean (continental baseline, CB) and regional emissions-influenced air. High NO_X levels at the site are observed for air from industrial regions of western Siberia and Ural Mountains, whereas CB air originates from remote areas of North Eurasia within 55°–70°N. The estimated annual means of daytime O₃ and NO_X mixing ratios for CB air are 27.0 and 0.44 ppbv, correspondingly, versus the similar quantities of 27.9 and 0.79 ppbv for all data. Monthly ozone for CB air shows a distinct maximum in April, as is the case for Northern Hemisphere midlatitude baseline (NHMLB) air at the European inflow boundary according to the surface ozone data for Mace Head and Norwegian monitoring sites, and a minimum in late summer–early autumn reflecting a weak continental-scale ozone production from biogenic sources of ozone precursors and wildfire emissions throughout the warm season. During spring and early summer under hot weather conditions, regional anthropogenic and wildfire emissions are an important source for ozone in the continental boundary layer over southern and central Siberia, resulting in surface ozone levels compared to or larger than those observed in NHMLB air. Throughout the remaining part of year, the central North Eurasia represents a sink for tropospheric ozone on a hemispheric scale.

中文翻译：

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臭氧前体排放对中西伯利亚 ZOTTO 高塔 NOX 和 O3 水平的区域影响

描述了 2007-2014 年间西伯利亚中部偏远地点 Zotino Tall Tower (ZOTTO)的近地表 NO _X (= NO + NO ₂ ) 和臭氧 (O ₃ ) 混合比的季节性变化。条件概率函数分析和回溯轨迹用于确定受清洁（大陆基线，CB）和区域排放影响空气的来源。观测到来自西西伯利亚西部和乌拉尔山脉工业区的空气的高 NO _X水平，而 CB 空气来自北欧亚大陆 55°–70°N 内的偏远地区。日间 O ₃和 NO _X的估计年平均值相应地，CB 空气的混合比为 27.0 和 0.44 ppbv，而所有数据的相似数量为 27.9 和 0.79 ppbv。根据 Mace Head 和挪威监测点的表面臭氧数据，CB 空气的月度臭氧在 4 月显示出明显的最大值，正如北半球中纬度基线 (NHMLB) 空气在欧洲流入边界的情况一样，在夏末出现最小值– 初秋反映了整个温暖季节中来自臭氧前体的生物源和野火排放的大陆尺度臭氧产量微弱。在炎热天气条件下的春季和初夏，区域人为和野火排放是西伯利亚南部和中部大陆边界层臭氧的重要来源，导致表面臭氧水平与 NHMLB 空气中观察到的水平相比或更高。在一年的剩余时间里，北欧亚大陆中部是半球尺度上对流层臭氧的一个汇。