1981~2017年四川省大气自净能力变化特征分析

利用四川省1981~2017年逐日地面气象观测资料和2017年1月环境监测资料，计算分析了四川省大气自净能力指数的时空变化特征及其影响因子，并初步探讨了2017年1月成都市大气自净能力指数与空气质量的关系.结果表明：四川省大气自净能力指数的分布形势以川西高原北部、川西高原南部、攀西地区、盆地西南部大气自净能力为较好到好，省内其余大部地区大气自净能力较差到差.近37a来，四川省、川西高原、攀西地区多年变化呈减弱趋势，四川盆地多年变化趋势不显著.影响因子中，四川省降水日平均大气自净能力指数小于非降水日.四川省以及各区域平均风速、通风量、风速较大日数和小风日数与大气自净能力指数呈显著正和负相关关系；混合层厚度与大气自净能力指数呈显著的正相关关系.

Analysis on the characteristics of atmospheric self-cleaning ability index in Sichuan Province from 1981 to 2017

Based on the meteorological data from 1981 to 2017 and the environmental air quality nitoring data in January 2017, the temporal and spatial characteristics of atmospheric self-cleaning ability index of Sichuan Province and its influcing factors were calculated and analyzed. The results showed that the distribution situation of the atmospheric self-cleaning ability index in Sichuan Province was that the atmospheric self-cleaning ability index in the north of western Sichuan Plateau, the south of Western Sichuan Plateau, Panxi region and the southwest of the basin was better to better, while the atmospheric self-cleaning ability index in the rest of the province was worse to worse. In recent 37 years, the annual change of Sichuan Province, Western Sichuan Plateau and Panxi area had been weakened, but the annual change of Sichuan Basin was not significant among the influcing factors, the average atmospheric self-cleaning ability index on precipitation days of Sichuan Province was smaller than that on non-precipitation days. There were obvious positive and negative correlation between the average wind speed, ventilation volume, the number of days of strong wind and the number of days of light wind and atmospheric self-cleaning ability index. The mixed layer thickness was positive correlate with the atmospheric self-cleaning ability index.