Fig.1

Spatial distribution of 32 automatic air monitoring stations in 18 cities of Hainan province"

Table 1

Statistics of regional O3 pollution events from 2015 to 2018 in Hainan province"

Table 2

Weather type statistics of regional O3 pollution events from 2015 to 2018 in Hainan province"

Fig.2

Distributions of O3-8h concentration under cold air westward circulation (a), cold air eastward circulation (b), warming high-pressure ridge (c), and tropical system (d) configurations from 2015 to 2018 in Hainan province"

Fig.3

Probability distributions of excessive O3-8h concentration under cold air westward circulation (a), cold air eastward circulation (b), warming high-pressure ridge (c), and tropical system (d) configurations from 2015 to 2018 in Hainan province"

Fig.4

Distributions of geopotential height field at 500 hPa (a), relative humidity, temperature and wind field at 850 hPa (b), and pressure at sea level, difference between air temperature and dew point temperature and wind at 10 m (c) under cold air westward circulation pattern"

Fig.5

Distributions of geopotential height field at 500 hPa (a), relative humidity, temperature and wind field at 850 hPa (b), and pressure at sea level, difference between air temperature and dew point temperature and wind at 10 m (c) under cold air eastward circulation pattern"

Fig.6

Distributions of geopotential height field at 500 hPa (a), relative humidity, temperature and wind field at 850 hPa (b), and pressure at sea level, difference between air temperature and dew point temperature and wind at 10 m (c) under warming high-pressure ridge pattern"

Fig.7

Distributions of geopotential height field at 500 hPa (a), relative humidity, temperature and wind field at 850 hPa (b), and pressure at sea level, difference between air temperature and dew point temperature and wind at 10 m (c) under tropical system pattern"