Department of Applied Physics, Faculty of Sciences, University of Valladolid, Paseo de Belén, 7, 47011 Valladolid, Spain.
Int J Environ Res Public Health. 2021 Aug 9;18(16):8397. doi: 10.3390/ijerph18168397.
Meteorological variables have a noticeable impact on pollutant concentrations. Among these variables, wind speed is typically measured, although research into how pollutants respond to it can be improved. This study considers nine years of hourly CO and CH measurements at a rural site, where wind speed values were calculated by the METEX model. Nine wind speed intervals are proposed where concentrations, distribution functions, and daily as well as annual cycles are calculated. Contrasts between local and transported concentrations are around 5 and 0.03 ppm for CO and CH, respectively. Seven skewed distributions are applied, and five efficiency criteria are considered to test the goodness of fit, with the modified Nash-Sutcliffe efficiency proving to be the most sensitive statistic. The Gumbel distribution is seen to be the most suitable for CO, whereas the Weibull distribution is chosen for CH, with the exponential function being the worst. Finally, daily and annual cycles are analysed, where a gradual decrease in amplitude is observed, particularly for the daily cycle. Parametric and nonparametric procedures are used to fit both cycles. The latter gave the best fits, with the agreement being higher for the daily cycle, where evolution is smoother than for the annual cycle.
气象变量对污染物浓度有显著影响。在这些变量中，通常会测量风速，尽管可以改进对污染物如何响应风速的研究。本研究考虑了一个农村站点 9 年的每小时 CO 和 CH 测量值，风速值是通过 METEX 模型计算的。提出了 9 个风速间隔，计算了浓度、分布函数以及日循环和年循环。CO 和 CH 的本地浓度与传输浓度之间的差异约为 5 和 0.03 ppm。应用了 7 个偏态分布，并考虑了 5 个效率标准来检验拟合优度，其中修正纳什-苏特克利夫效率被证明是最敏感的统计量。Gumbel 分布被认为最适合 CO，而 Weibull 分布被选为 CH，指数函数最差。最后，分析了日循环和年循环，观察到幅度逐渐减小，特别是对于日循环。使用参数和非参数程序来拟合这两个周期。后者给出了最佳拟合，日循环的拟合度更高，因为它的演变比年循环更平滑。
