山东省O3污染概况及预报效果评估

对山东省各市2018—2021年的O₃污染特征进行了分析,并对2021年5—9月O₃污染较重月份空气质量模型的O₃预报结果进行了分析评估。结果表明:山东省2018—2021年O₃-8 h第90百分位数(O₃-8 h-90per)先升高后降低,O₃污染呈现波动变化,污染月主要集中在5—9月,并呈现内陆高、沿海低,中北部高、南部低的空间分布特征。集合预报模式对O₃模拟效果最好,预测结果与O₃监测值的相关性最大、偏差最小,但较难预测出O₃的峰值浓度,易漏报O₃重度污染。WRF-Chem、CMAQ、CAMx、NAQPMS对O₃的模拟效果比集合预报稍差,CMAQ、CAMx存在系统性偏低的情况,但对优级别的模拟效果明显好于其他模式;WRF-Chem、NAQPMS存在系统性偏高的情况,WRF-Chem能较好地模拟出O₃超标日,对中度、重度日的24h级别准确率分别达94.08%、100%,对O₃超标预报尤其是中至重度污染的预测预报有重要指导意义。

Pollution Characteristics and Evaluation on Predication Efforts of O3 in Shandong Province

In this paper,the characteristics of O₃ pollution in cities of Shandong Province from 2018 to 2021 were analyzed,and the O 3 forecast results of the air quality models in the months with heavier O₃ pollution from May to September 2021 were analyzed and evaluated. The results showed that the average annual concentration of O₃ -8 h (90th 90th percentile) increased first and then decreased in Shandong Province from 2018 to 2021,while O₃ pollution fluctuated. The pollution months were mainly from May to September,and the spatial distribution characteristics were "higher in inland,lower in coastal areas",and "higher in central and northern areas,and lower in southern areas". The Ensemble Forecast Model had the best effect on O₃ simulation, and its forecasting results had the largest correlation with O₃ monitoring values and the minimum deviation. However,it was difficult to predict the peak concentration of O₃,and it was easy to miss the report of severe O₃ pollution. The simulation effects of WRFChem,CMAQ,CAMx and NAQPMS on O₃ were slightly worse than that of Ensemble Forecast Model. The simulation effect of CMAQ and CAMx on the days of excellent air quality was obviously better than other models, but their forecast results were systematically lower. However, the forecast results of WRF-Chem and NAQPMS were systematically higher. WRF-Chem could better simulate the days when O₃ exceeding the standard,and its 24-hour accuracy on days of moderate and severe air quality was 94. 08% and 100%,which was important on guiding the forecast of O₃ exceeding the standard,especially of moderate to severe pollution.