2015—2020年中国三大城市群臭氧浓度时空变化特征及影响因子

针对中国京津冀、长三角、珠三角三大城市群，分析了2015—2020年三大城市群的臭氧浓度时空变化特征，基于随机森林模型和地理探测器模型分别研究了影响其时间变化和空间变化的主要因子。结果表明：1）2015—2020年三大城市群臭氧浓度整体呈逐年升高的时空演变特征。其臭氧变化率存在中部向南北递减的趋势，即长三角（3.4%）>京津冀（2.9%）>珠三角（2.1%）；臭氧浓度平均值呈北高南低的空间变化特征，即京津冀（98.3 μg/m³）>长三角（96.7 μg/m³）>珠三角（90.5 μg/m³）。2）温度、风速、人均GDP和能源消耗量不仅是影响三大城市群臭氧浓度时间变化的主要因子，而且与臭氧浓度存在着阈值效应。3）能源消耗量和人均GDP是影响三大城市群臭氧浓度空间变化的主要因子，其对臭氧浓度空间变化的解释率均超过36%。今后关于城市群臭氧的防控应更关注经济发达地区，并通过重点监测和预警高耗能区等手段，达到城市群臭氧防治效果。

Spatio-temporal variation characteristics and influencing factors of ozone in three major urban agglomerations in China from 2015 to 2020

The spatio-temporal variation characteristics of ozone concentration in the three major urban agglomerations of Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta in China from 2015 to 2020 were analyzed, and the main factors affecting temporal and spatial changes were studied based on random forest model and geographical detector model. The results showed that: 1) From 2015 to 2020, the temporal and spatial evolution characteristics of ozone concentration values of the three urban agglomerations showed an increasing trend year by year, and the ozone variation rate showed a trend of "decreasing from the central to the south": Yangtze River Delta (3.4%) > Beijing-Tianjin-Hebei (2.9%) > Pearl River Delta (2.1%). The spatial variation characteristics of the average ozone concentration were "high in the north and low in the south": Beijing-Tianjin-Hebei (98.3 μg/m3) > Yangtze River Delta (96.7 μg/m3) > Pearl River Delta (90.5 μg/m3). 2) Temperature, wind speed, GDP, and energy consumption were not only the main factors affecting the temporal variation of ozone in the three urban agglomerations, but also had a threshold effect on ozone concentration. 3) Energy consumption and GDP were the main factors affecting the spatial change of ozone concentration in the three urban agglomerations, and their interpretation rates were more than 36%. Therefore, for ozone prevention and control in urban agglomerations more attention should be paid to economically developed areas, and key monitoring and early warning should be carried out in high energy consuming areas to achieve the effectiveness of ozone prevention and control in urban agglomerations.