Another round of heavy pollution weather is coming in Sichuan

At midnight on December 23rd, Chengdu will issue a yellow warning for heavy pollution weather. The reporter learned that at the same time, Meishan, Yibin, Neijiang, Guang'an and other places have also timely released warning information to the society

Another round of polluted weather is coming, what is the forecast for this round of pollution? Why does polluted weather like to "visit" Sichuan in winter? When will the air quality improve? On December 22nd, Tang Zhaojun, Deputy Director of the Atmospheric Room at the Sichuan Provincial Ecological Environment Monitoring Station, provided a detailed interpretation of the pollution situation in this round

This round of pollution process is a large-scale regional pollution.

According to the joint consultation opinions of the ecological environment and meteorological departments of Sichuan and Chongqing, it is expected that from December 23rd, the meteorological conditions in most parts of the basin will further deteriorate, and the regional pollution weather will worsen. Most cities will experience mild to moderate pollution processes, and some cities in the Chengdu Plain, southern and central parts of the basin are at risk of moderate to severe particulate matter pollution.. According to predictions, there will be mild to moderate pollution risks in cities such as Chengdu, Deyang, Mianyang, Suining, and Ziyang, and moderate to severe pollution risks in cities such as Leshan, Zigong, and Luzhou. From the overall pollution situation, this round of pollution process is a large-scale regional pollution process

Why does polluted weather like to "visit" Sichuan in winter

Overall, under unfavorable meteorological conditions such as static stability, high humidity, and temperature inversion, combined with anthropogenic emission factors such as industrial sources, dust sources, mobile sources, and non-point sources, pollutants in the basin will accumulate more and more Tang Zhaojun introduced that according to the monitoring situation in recent years, as we enter autumn and winter, the pollutant emissions of some enterprises near the end of the year are significantly higher than in other seasons, even exceeding the regional environmental capacity, leading to an increase in atmospheric pollution

Specifically, the terrain of the Sichuan Basin is relatively closed and the environmental capacity is limited. When encountering stable weather, most areas of the basin have low wind speeds. In addition, the temperature difference between day and night in winter increases, making it easy to have inversion layers in the morning and evening, which is not conducive to the diffusion of atmospheric pollutants. The combination of stable weather and inversion layer, accompanied by the gradual increase of air humidity in the basin, leads to the growth of particulate matter moisture absorption and accelerated secondary transformation of pollutants, resulting in the continuous accumulation of particulate matter and ultimately pollution

In addition, industrial sources, dust sources, mobile sources, and non-point sources continuously emit pollutants during production and daily life, resulting in the accumulation of pollutants in the basin, which exceeds the regional environmental capacity and has a significant impact on air quality. This is the fundamental reason for the occurrence of pollution processes

When will the air quality improve

According to the forecast, from December 23rd to 25th, most parts of the Sichuan Basin will be cloudy, gradually transitioning to a stable state, with pollutants accumulating continuously, and some cities facing mild to moderate pollution risks. On the 26th and 27th, there was a slight increase in wind in the basin, but the overall meteorological conditions did not improve significantly, and pollutants continued to accumulate. Some cities may have moderate to severe pollution risks

On the 28th and 29th, due to the influence of weak north winds, the sky gradually cleared up and the vertical diffusion conditions improved, but the improvement was limited. Most cities in the basin are mainly at risk of good to mild pollution

On the 30th and 31st, due to the influence of cold air from the western road entering Sichuan, most parts of the basin will experience increased winds, and air quality is expected to gradually improve from north to south. However, the southern part of the Chengdu Plain and the southern Sichuan region will be affected by air mass compression and transmission, and the risk of particulate matter pollution still exists

It is worth noting that due to the high uncertainty of recent cold air activity and precipitation, the situation may change in the later stage and needs to be continuously tracked

How to reduce the impact of light pollution weather on the public

The reporter learned that according to the emergency plan for heavy pollution weather in Sichuan Province, the Department of Ecology and Environment will hold encrypted consultations and judgments with meteorological, transportation, housing and construction, economic and information technology, public security and other departments, and issue warning and suggestion letters to relevant city governments, suggesting to activate corresponding levels of heavy pollution weather warning or strengthen control measures. At the same time, real-time monitoring of changes in air quality, timely release of warning information, and raising public awareness of health protection

According to the prediction results, during this round of pollution, key cities such as Chengdu, Luzhou, Yibin, Neijiang, Zigong, Leshan, Meishan, etc. will activate emergency warning responses. Construction sites, industrial enterprises, etc. will cooperate to implement emergency measures for heavy pollution, reduce pollutant emissions, and minimize the impact of heavy pollution weather to the greatest extent possible, fully ensuring the health of the people

Tang Zhaojun suggested that the general public should try to minimize going out during the warning period and continue to pay attention to the weather changes released by ecological environment, meteorological and other departments. Outdoor activity personnel can take necessary protective measures such as wearing masks and shortening outdoor activity time. It is recommended that children, the elderly, and patients with respiratory, cardiovascular, and other chronic diseases avoid outdoor activities as much as possible