An instrument for in situ measurement of total ozone reactivity
An instrument for in situ measurement of total ozone reactivity
复制标题
DOI：
10.5194/amt-13-1655-2020
复制
发表时间：
2019-08
影响因子：
3.8
通讯作者：
R. Sommariva;L. Kramer;L. Crilley;M. S. Alam;W. Bloss
中科院分区：
文献类型：
--
作者：
R. Sommariva;L. Kramer;L. Crilley;M. S. Alam;W. Bloss
抽象的。我们提出了一种测量臭氧总反应性的仪器-臭氧（O3）的化学寿命的倒数-在对流层。总臭氧反应系统（TORS）的开发目的是研究生物挥发性有机化合物（BVOC）作为对流层臭氧化学汇的作用。该仪器在实验室中使用铁氟龙袋中的单个BVOCs和小植物（柠檬百里香，Thoracitriodorus）进行了广泛的表征和测试，并证明能够测量对应于>4.5×10-5 s−1的反应性（5分钟平均时间），估计总不确定度为1.32%。这种反应性相当于α-蒎烯>20 ppb或异戊二烯>150 ppb-高于典型的环境水平，但在环境室和封闭实验以及富含BVOC的环境中可观察到。TORS的功能在准环境条件下进行了演示，并在包含一系列芳香植物的园艺温室中进行了部署。温室中臭氧总反应性的测量结果显示出明确的昼夜模式，BVOCs的排放量，并与十亿分之几十的单萜和十亿分之几的倍半萜的混合比是一致的。
Abstract. We present an instrument for the measurement of total ozone reactivity – the reciprocal of the chemical lifetime of ozone (O3) – in the troposphere. The Total Ozone Reactivity System (TORS) was developed with the objective to study the role of biogenic volatile organic compounds (BVOCs) as chemical sinks of tropospheric ozone. The instrument was extensively characterized and tested in the laboratory using individual BVOCs and small plants (lemon thyme, Thymus citriodorus) in a Teflon bag and proved able to measure reactivities corresponding to >4.5×10-5 s−1 (at 5 min averaging time), with an estimated total uncertainty of ∼32%. Such reactivities correspond to >20 ppb of α-pinene or >150 ppb of isoprene in isolation – larger than typical ambient levels but observable in environmental chamber and enclosure experiments as well as in BVOC-rich environments. The functionality of TORS was demonstrated in quasi-ambient conditions with a deployment in a horticultural glasshouse containing a range of aromatic plants. The measurements of total ozone reactivity made in the glasshouse showed a clear diurnal pattern, following the emissions of BVOCs, and are consistent with mixing ratios of tens of parts per billion of monoterpenes and several parts per billion of sesquiterpenes.