Analysis of Temporal and Spatial Variation Characteristics of Air Quality in the Pearl River Delta during 2015-2019

Abstract Based on the history monitoring data of Air Quality Index (AQI) during 2015-2019, we conducted a contrastive analysis of the temporal and spatial variation characteristics of air quality in the Pearl River Delta. Results showed that the variation trends of AQI annual averages in the Pearl River Delta were basically the same. The AQI annual averages rose after decline and the variation curves were W-shaped. In the Pearl River Delta, Shenzhen and Huizhou enjoyed better air quality. In this region, AQI quarterly averages were high in autumn and winter but low in summer, and in a same year, the variation trends of the nine cities were basically the same. In autumn, the ozone concentration increased dramatically and therefore ozone became a major pollutant in ambient air. In winter, Guangzhou, Shenzhen and Dongguan saw a double-peak phenomenon in AQI hourly values, which rose at rush hours.