主办单位:中国气象局沈阳大气环境研究所
国际刊号:ISSN 1673-503X
国内刊号:CN 21-1531/P

Journal of Meteorology and Environment ›› 2023, Vol. 39 ›› Issue (1): 44-54.doi: 10.3969/j.issn.1673-503X.2023.01.006

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Study on hourly PM2.5 concentration forecast based on XGBoost method in Xi'an city

Xu-ting ZHANG1,2(),Hui LIU2,3,Rui-fang LIU2,4,*(),Fei JU2,5,Jia-hui-min LIU2,3,Xing-xing GAO2,3,Shao-ni HUANG2,3,Nan WANG2,5   

  1. 1. Shaanxi Meteorological Service Center of Agricultural Remote Sensing and Economic Crops, Xi'an 710016, China
    2. Key Laboratory of Eco-Environment and Meteorology for the Qinling Mountains and Loess Plateau, Shaanxi Meteorological Service, Xi'an 710016, China
    3. Shaanxi Meteorological Observatory, Xi'an 710014, China
    4. Xi'an Meteorological Service, Xi'an 710016, China
    5. Meteorological Institute of Shaanxi Province, Xi'an 710016, China
  • Received:2022-07-28 Online:2023-02-28 Published:2023-03-27
  • Contact: Rui-fang LIU E-mail:zhang_xuting26@126.com;26886083@qq.com

Abstract:

Based on the eXtreme Gradient Boosting (XGBoost) machine learning algorithm model, using hourly PM2.5 concentration monitoring data and meteorological observation data in Xi'an from 2016 to 2021, the forecast test of hourly PM2.5 concentration was carried out by selecting meteorological and time factors as the input features.The results showed that PM2.5 concentration has a significant negative correlation with average temperature and visibility, and relative humidity and dew point temperature are significantly positively correlated with PM2.5 concentration in winter.Easterly wind is more likely to produce heavily polluted weather.Generally, air pollution occurs frequently from the end of December to the beginning of January, but the PM2.5 concentration is decreasing year by year.The PM2.5 concentration in winter shows the most obvious bimodal diurnal variation with the highest values appearing in the early morning and around 11:00.Meanwhile, there is a "weekend effect" in the change of PM2.5 concentration.The forecast model can truly reflect the changes of PM2.5 concentration magnitude and trend with the determination coefficient of 0.77, the mean absolute error of 12.79 μg·m-3 and the root mean square error of 18.68 μg·m-3 between forecasted and observed values.The model has a relatively stable performance and better effect in forecasting PM2.5 concentration in autumn and winter than in spring and summer but underestimates the extreme peaks.Besides, the forecast model has good interpretability and is clearly influenced by the visibility feature variables and the importance of feature variable such as dew point temperature, relative humidity, average temperature, and sea level pressure decrease in turn.Meanwhile, the time factors have a certain impact on the model.In addition, the forecast accuracy and efficiency of this model are higher than those of other statistical and machine-learning models.

Key words: PM2.5 concentration, eXtreme Gradient Boosting, Machine learning, Meteorological factors, Forecast

CLC Number: