China News Service, May 18. According to the official WeChat news of the Ministry of Ecology and Environment, the Ministry of Ecology and Environment notified the media on the 18th of the national ambient air quality in April and January-April 2022.

In April, the average number of days with good air quality in 339 cities at the prefecture level and above was 89.0%, a year-on-year decrease of 3.5 percentage points.

Overall situation

　　In April, the average number of days with good air quality in 339 cities at the prefecture level and above was 89.0%, a year-on-year decrease of 3.5 percentage points; the average PM2.5 concentration was 28 micrograms/m3, the same as the same period last year; the average PM10 concentration was 56 micrograms/cubic m, an increase of 3.7% year-on-year; the average concentration of O3 was 145 micrograms/cubic meter, a year-on-year increase of 12.4%; the average concentration of SO2 was 9 micrograms/cubic meter, an increase of 12.5% ​​year-on-year; the average concentration of NO2 was 19 micrograms/cubic meter, a year-on-year decrease of 17.4% %; the average concentration of CO was 0.8 mg/m3, a year-on-year decrease of 11.1%.

　　From January to April, the average number of days with good air quality in 339 cities at the prefecture level and above was 85.1%, up 1.3 percentage points year-on-year; the average PM2.5 concentration was 39 micrograms/m3, down 4.9% year-on-year; the average PM10 concentration was 63 micrograms/m3, down 8.7% year-on-year; the average concentration of O3 was 127 micrograms/m3, up 8.5% year-on-year; the average SO2 concentration was 9 micrograms/m3, down 18.2% year-on-year; the average NO2 concentration was 24 micrograms/m3 , down 11.1% year-on-year; the average CO concentration was 1.2 mg/m3, down 7.7% year-on-year.

Proportion of days at each level in 339 cities at the prefecture level and above from January to April 2022

Concentrations and year-on-year changes of six indicators in 339 prefecture-level and above cities across the country from January to April 2022

key area

　　In April, the average number of good days in the "2+26" cities in Beijing-Tianjin-Hebei and surrounding areas was 81.8%, a year-on-year decrease of 2.7 percentage points; the PM2.5 concentration was 39 micrograms per cubic meter, the same year-on-year.

From January to April, the average number of days with good quality was 68.1%, an increase of 4.9 percentage points year-on-year; the PM2.5 concentration was 57 micrograms per cubic meter, a year-on-year decrease of 1.7%.

　　The proportion of good days in Beijing in April was 76.7%, a year-on-year decrease of 13.3 percentage points; the PM2.5 concentration was 35 micrograms per cubic meter, a year-on-year increase of 12.9%.

From January to April, the proportion of good days was 86.7%, a year-on-year increase of 20.0 percentage points; the PM2.5 concentration was 36 micrograms/m3, a year-on-year decrease of 32.1%.

　　The average number of good days in 41 cities in the Yangtze River Delta region in April was 84.5%, a year-on-year decrease of 9.7 percentage points; the PM2.5 concentration was 29 micrograms/m3, a year-on-year decrease of 3.3%.

From January to April, the average number of days with good quality was 82.8%, a year-on-year decrease of 6.3 percentage points; the PM2.5 concentration was 42 micrograms/m3, a year-on-year increase of 7.7%.

　　The average number of good days in 11 cities in the Fenwei Plain in April was 88.2%, the same as the same period last year; the PM2.5 concentration was 35 micrograms per cubic meter, down 2.8% year-on-year.

From January to April, the average number of days with good quality was 59.6%, a year-on-year decrease of 5.9 percentage points; the PM2.5 concentration was 65 micrograms/m3, a year-on-year increase of 12.1%.

Comparison of air quality in the country and key regions from January to April 2022

Ranking of key cities

　　In April, among the 168 key cities, 20 cities including Haikou, Lhasa and Zhoushan had relatively good air quality (from 1st to 20th); 20 cities including Hebi, Baoding and Xinxiang had relatively poor air quality (From the bottom 1 to the tie for the bottom 19), see Schedule 1.

　　From January to April, among the 168 key cities, 20 cities including Lhasa, Haikou and Zhoushan had relatively good air quality (from 1st to 19th); 20 cities including Xianyang, Urumqi and Xi'an had relatively good air quality Relatively poor (from bottom 1 to bottom 20), see Table 2.

　　Schedule 1

　　List of the top 20 and bottom 20 cities in the air quality ranking of 168 key cities in April 2022

　　Schedule 2

　　List of top 20 and bottom 20 cities in air quality rankings of 168 key cities from January to April 2022