China News Service, July 21. On July 21, the Ministry of Ecology and Environment held a regular press conference in July. Liu Youbin, spokesperson of the Ministry of Ecology and Environment, introduced that from the perspective of the past five years, the concentration of O₃ in my country has generally remained relatively stable. , the national O₃ concentration rebounded in the first half of this year.
At the meeting, a reporter asked: Recently, the Ministry of Ecology and Environment reported the quality of the national ecological environment in the first half of the year. The data shows that the current national ozone concentration has rebounded.
What is the reason for the rebound?
What measures have been taken to control ozone pollution?
How effective is it?
How to continue to strengthen ozone management?
Liu Youbin said that from January to June 2022, the national ambient air quality will generally improve, and the proportion of good days in 339 cities will be 84.6%, an increase of 0.3 percentage points year-on-year.
The concentration of six major pollutants "five drops and one liter", of which the concentration of PM2.5 decreased by 5.9% year-on-year, and only the concentration of O3 increased by 4.3% year-on-year.
Liu Youbin said that the O₃ secondary standard limit of my country's "Ambient Air Quality Standard" is 160 micrograms per cubic meter, which is consistent with the WHO standard.
From the perspective of the past five years, the O₃ concentration in my country has generally remained in a relatively stable state.
From 2018 to the first half of 2022, the national O₃ concentrations were 143, 143, 141, 138, and 144 μg/m3, respectively. Although there were slight fluctuations between years, the overall level was basically stable at around 140 μg/m3.
Liu Youbin pointed out that the national O3 concentration rebounded in the first half of this year, mainly due to the following two reasons.
First, the emissions of precursors are still at a high level.
Studies have shown that among the four major air pollutants in my country, the emissions of SO₂ and primary PM2.5 have dropped to the level of one million tons, while the emissions of NOx and VOCs, the precursors of O₃ pollution, are still at the level of ten million tons.
Second, the weather conditions are generally unfavorable.
From April to June this year, key regions such as Beijing-Tianjin-Hebei and surrounding areas, the Yangtze River Delta region, and the Fenwei Plain have increased year-on-year temperature, decreased precipitation, and decreased humidity. A significant year-on-year increase has led to a rebound in O₃ pollution across the country.
Liu Youbin also said that the Ministry of Ecology and Environment has officially launched the summer supervision and assistance work for air quality improvement in key areas since May, focusing on Beijing-Tianjin-Hebei and surrounding areas, the Fenwei Plain, and the border areas of Jiangsu, Anhui, Shandong and Henan, focusing on enterprises in key industries. Efforts will be made to solve the outstanding problems causing ozone pollution.
Liu Youbin said that this summer, the supervision and assistance will be carried out in the form of online supervision and assistance, taking into account the situation of epidemic prevention and control and the requirements of stabilizing the economic market. A remote online supervision and assistance information platform will be established, and big data will be used to accurately identify problem clues and push tasks online. Checklist to guide localities to carry out on-site investigation.
Liu Youbin introduced that as of July 20, more than 5,000 problem clues have been sent to 89 cities.
Ecological and environmental departments at all levels carried out in-depth on-site investigations, rectified a number of prominent environmental problems, and promoted the coordinated emission reduction of VOCs and NOx.
Liu Youbin said that the next step will be to promote the introduction of the "Comprehensive Air Quality Improvement Action Plan", continue to strengthen the prevention and control of PM2.5 pollution, at the same time carry out comprehensive treatment of VOCs and source replacement, promote the coordinated emission reduction of VOCs and NOx, and effectively curb the growth of ozone concentration. The trend is that by 2025, the total emissions of VOCs and NOx will decrease by more than 10% compared with 2020, and the coordinated control of PM2.5 and O₃ will be realized, and the ambient air quality will be comprehensively improved.