台中地區空氣污染物之頻率分布特性

The Distributional Characteristics of Air Pollutants in Taichung Area, Taiwan

盧信忠(Hsin-Chung Lu) ； 廖雅雲(Ya-Yun Liao) ； 張曉玲(Hsiao-Ling Chang)

《弘光學報》 39期 (2002/05) Pp. 67-74

https://doi.org/10.6615/HAR.200205.39.08

摘要

空氣污染物之濃度經常會隨著大氣條件及污染物排放量而變，由大氣污染物濃度之統計機率分布，可用來判斷污染物超出空氣品質標準上限的頻率，進而作為訂定空氣品質標準或排放標準之參考。本研究中利用環保署測站資料，選取台中地區1995至1999年忠明、西屯、大里及豐原四個測站資料，進行PM_(10), PM_(2 5)及O_3之濃度頻率分析，使用三種統計分布lognormal、Weibull及type V Pearson分布來模擬PM_(10)、O_3及PM_(2.5)的頻率分布情形。本研究採用1995~1999之監測資料推估所得之分布參數預測2000年空氣污染物之頻率分布。此外並以K-S (Kolmogorov-Smimov)test判斷何種理論分布最適合空氣污染物之頻率分布。並預測2000年超出空氣品質標準上限的頻率。結果顯示各個空氣污染物濃度分布非常相似，整體而言PM_(10)、O_3及PM_(2.5)的機率分布皆較符合lognormal分布，忠明、西屯、大里及豐原四個測站中，PM_(10)、O_3及PM_(2.5)分布歷年來之形狀因子幾乎不變，顯示大氣狀況對測站歷年之空氣污染物濃度頻率分布之影響類似。此外推估所得2000年超出空氣品質標準之天數與實際值相當符合，此研究結果可當為空氣污染物控制策略之參考。

關鍵字

Weibull分布 ； type V Pearson分布

並列摘要

The concentrations of air pollutants are usually random variables and correlated with the emission levels and meteorological conditions. The lognormal, Weibull and type V Pearson distributions were taken to fit the PM_(10), PM_(2.5)and O_3concentration frequency distributions in Taichung area. Air quality data from 1995 to 1999 at four stations, Chung-Min, Hsi-Tuen, Da-Li and Feng-Uan, were fitted with three distributions. The distributional parameters at 2000 can be estimated from the parameters obtained from the measured data of 1995~1999. The Kolmogorov-Smirnov (K-S) test is used as criteria to judge the goodness-of-fit of these three distributions. Moreover, the probability of pollutants exceeding the air quality standard is also predicted for year 2000. These results show that the frequency distributions of air pollutants are similar. In general, the lognormal distribution is the most adequate to represent the frequency distribution of pollutants. The shape factors of PM10 distribution are almost the same from 1995 to 1999 at Chung-Min, Hsi-Tuen, Da-Li and Feng-Uan stations. The distributions of PM_(2.5) and O_3 have the similar results. This phenomenon shows that the meteorological conditions have the similar influence on these air pollutants for every year. Moreover, the days exceeding the air quality standard at year 2000 are successfully predicted. The information obtained from this study is useful for developing air pollution control strategy in Taiwan area.

並列關鍵字

type V Pearson ； Weibull ； lognormal ； K-S test

參考文獻

Mage, D.T., and Ott, W. R. (1984) An Evaluation of the Method of Fractiles, Moments and Maximum Likedlihood for Estimating Parameters when Sampling Air Quality Data from a Stationary Lognormal Distribution. Atmospheric Environment, 18, pp. 163-171.

Mage, D.T., and Ott, W. R. (1978) Refinements of the Lognormal Probability Model for Analysis of Aerometric Data. J. Air Pollut. Control Ass., 28, pp.796-798.

Kao, A. S., and Friedlander, S. K. (1995) Frequency Distributions of PM10 Chemical Components and Their Sources. Environ. Sci. and Technol., 29, pp.19-28.

Georgopoulos, P. G. and Seinfeld, J. H. (1982) Statistical Distribution of Air Pollutant Concentration. Environ. Sci. and Technol., 16, pp. 401A-416A.

Morel, B., Yen, S. and Cifuentes, L. (1999) Statistical Distribution for Air Pollutant Applied to the Study of Particulate Problem in Santiago. Atmospheric Environment, 33, pp. 2575-2585.