Shenzhen's air quality achieved a significant milestone last year with no hazy days being recorded, the first time ever since monitoring began, according to the city's ecological environment monitoring center.
From January to June of this year, Shenzhen ranked fourth in air quality among 168 key cities and first among megacities in China.
In 2023, the percentage of days with good air quality in Shenzhen increased to 97.8%, ranking third nationwide and meeting the World Health Organization (WHO) Phase II standard of <25 micrograms per cubic meter for fine particles (PM2.5). The average ozone concentration decreased by 17 micrograms per cubic meter compared with 2022.
Ozone has emerged as a primary pollutant in Shenzhen in recent years, largely due to volatile organic compounds (VOCs) released by industrial activities, according to Sun Tianle, vice head of the monitoring center.
VOCs usually originate from automobiles, industrial manufacturing, utilization of services and facilities by the public, the combustion of any type of fuel, the storage and transportation of oil, furniture and machine coatings, and cooking oil fumes.
Last year, Shenzhen launched a campaign for VOC control in key industrial areas, starting with Bao'an District as a pilot. The efforts resulted in a 10.6% reduction in the concentration of ozone in Bao'an.
The city has developed an air quality monitoring network that covers all 74 subdistricts and an advanced atmospheric photochemical pollution monitoring network covering 11 districts.
Shenzhen is also home to the world's tallest three-dimensional high-altitude station at 513 meters, which serves as a high-precision, stable, and proficient observatory for the continuous monitoring of upper-air climate.
At present, Shenzhen is actively using AI technology to conduct more accurate air quality forecasting, according to Sun.