Changing supersites: assessing the impact of the southern UK EMEP supersite relocation on measured atmospheric composition
Changing supersites: assessing the impact of the southern UK EMEP supersite relocation on measured atmospheric composition
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改变超级站点：评估英国南部 EMEP 超级站点搬迁对测量的大气成分的影响
DOI：
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发表时间：
2019
影响因子：
2.9
通讯作者：
M. Twigg
中科院分区：
文献类型：
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作者：
H. Walker;M. Heal;C. Braban;S. Ritchie;C. Conolly;A. Sanocka;U. Dragosits;M. Twigg
2016年1月，英国南欧监测和评估计划（EMEP）的2级空气污染监测“supersite”从牛津郡的哈威尔搬迁到汉普郡的奇尔博尔顿天文台。由于没有进行共址研究，这项工作回顾性调查是否supersite搬迁导致的不连续性的时间序列中的浓度通常研究的气体污染物（NOx，NH3，SO2和O3）和颗粒物（PM2.5和PM10）。结合气象变量和当地排放数据，分析了搬迁前和搬迁后两年（分别为2014-15和2016-17）的测量结果。将deweather包应用于级联时间序列，以最大限度地减少气象影响。PM2.5、PM10、SO2和O3的平均浓度相似，但NOx和NH3的平均浓度差异很大（分别增加了1.6倍和1.3倍）。奇尔博尔顿的NH3浓度相当高，这是由于靠近混合农田，特别是一个强大的西南来源，贡献了年平均值的50%。从M3高速公路和大伦敦等来源来看，到达奇尔博尔顿的东风中的氮氧化物和颗粒物浓度分别是哈维尔的2.7倍和1.5倍。西风的氮氧化物浓度保持相似，因此尽管西风频率较高，年平均浓度较高。来自西部的PM浓度较低，导致年平均值相似。二次无机和黑碳成分PM大致相似的网站之间。在奇尔博尔顿的平均氮氧化物和氨的差异，必须考虑到在英国南部supersite数据的基础上考虑长期的区域趋势。
In January 2016 the United Kingdom’s southern European Monitoring and Evaluation Programme (EMEP) level-2 air pollution monitoring ‘supersite’ was relocated from Harwell, Oxfordshire to Chilbolton Observatory, Hampshire. As no co-location study was undertaken, this work retrospectively investigates whether the supersite relocation has led to discontinuities in the time series of concentrations of commonly studied gaseous pollutants (NOx, NH3, SO2 and O3) and particulate matter (PM2.5 and PM10). Two years of measurements pre- and post-relocation (2014–15 and 2016–17 respectively) were analysed in conjunction with meteorological variables and local emission data. The deweather package was applied to the concatenated time series to minimise the influence of meteorology. Similar average concentrations of PM2.5, PM10, SO2 and O3 were observed, but there were substantial differences in that of NOx and NH3 (increase by factors of ∼1.6 and ∼3, respectively). The considerably higher NH3 concentrations at Chilbolton are attributed to the close proximity of mixed farmland, in particular to a strong south-westerly source contributing to ∼50% of the annual average. NOx and PM concentrations in easterly winds arriving at Chilbolton are ∼2.7 and ∼1.5 times larger than at Harwell, from sources including the M3 motorway and Greater London. Westerly concentrations of NOx remain similar, therefore despite a higher frequency of westerly wind, annual mean concentrations are larger. Lower concentrations of PM arriving from the west result in similar annual averages. The secondary inorganic and black carbon components of PM were broadly similar between the sites. The differences in average NOx and NH3 at Chilbolton must be taken into account when considering long-term regional trends based on the southern UK supersite data.