Beijing's next air quality report will include PM2.5

Yan Ming, who lives in the Daxing District of Beijing, will take her 5-year-old child out of the door almost every weekend. However, on the evening of Friday, December 14, when he checked the air quality forecast on the Internet, he immediately dismissed the idea of ​​taking children to the park the next day. Forecasts show that the air quality over the weekend is very poor. "When it's bad, stay home. I don't want my child to go out and become a vacuum cleaner."

Yan Ming’s attention to air quality forecast has been carried out in Beijing for 11 years. This year’s New Year’s Day forecast is about to change face, and the forecast content will change greatly. From January 1, 2013, Beijing and other places will begin to implement the newly revised Ambient Air Quality Standard. The main pollutants targeted by the air quality forecast and daily report will be increased from the “oldest three items” to six items, including the wide range of social Concern about PM2.5, while the limits of some pollutants will be tightened.

The air quality index is closer to the public

At present, Beijing's external air quality forecast will divide the city into six districts of the city, the northwest, northeast, southeast, and southwest, and forecast the "primary pollutants" and "air pollution index" for the next 24 hours. .

The reporter learned from the Beijing Municipal Environmental Protection Monitoring Center that the air quality forecast will continue to take the form of five regional forecasts since New Year's Day next year, but the primary pollutants included in the forecast content will be in the existing PM10 (inhalable particulates), Based on sulfur dioxide and nitrogen dioxide, three new pollutants were added: PM2.5, carbon monoxide, and ozone. In fact, starting from this month, the center has added 3 internal consultations on new pollutants in its forecasting business.

Qiu Qihong, a high-quality engineer at the Beijing Environmental Protection Monitoring Center, said that a significant change next year is the possibility of several pollutants being listed as primary pollutants. For the forecast and daily report carried out according to the old standards, one of the three oldest pollutants must be selected as the primary pollutant. However, if New Year's Day begins next year, if the sub-index of several pollutants is tied high, then these pollutants are also the primary pollutants.

“However, PM2.5 will undoubtedly be the “culprit.” According to preliminary estimates by the environmental protection department in Beijing, over half of the time in Beijing, the primary pollutant will be PM2.5. In next year's air quality forecast, PM2.5 will Frequent appearance." Qiu Qihong stressed.

In addition, the current “air pollution index” in the air quality forecast and daily report will be adjusted to the “air quality index,” and there will be major changes in the grading and names of all levels. The air pollution index is divided into seven levels: excellent, good, light, light, medium, medium, and heavy. Three days were subdivided into minor pollution and mild pollution. The four days were subdivided into moderate pollution and moderate pollution, which increased the difficulty of public understanding.

The Air Quality Index (AQI) Technical Regulations (Trial), implemented in parallel with the newly revised Ambient Air Quality Standards, classifies the Air Quality Index into six levels, of which, moderate pollution (Level 4) and the index 151-200; Severe pollution (Grade 5), index 201-300; Severe pollution, index greater than 300.

According to preliminary estimates by the environmental protection department, according to the new grading standard, the number of “blue skies” (first and second day) in Beijing next year will drop significantly. However, this does not mean that the air quality level itself will change significantly next year, but because the new standards have been tightened, the assessment of air quality has changed significantly. Qiu Qihong believes that “according to the new standards, the forecast is more in line with the actual situation and closer to the intuitive feelings of the public. It is good for the public to look at the weather forecast, and to use the air quality forecast to seek advantages and avoid disadvantages, and to arrange trips and life rationally.”

On December 14th, Beijing released the Air Heavy Pollution Day Emergency Plan (Interim). It is expected that air quality warnings will be issued when heavy pollution weather occurs, and emergency mechanisms will be activated in a timely manner. In a standardized and systematic manner, according to the heavy pollution level, Implement emergency measures such as emission limits for key emission sources, stop earthworks on construction sites, and restrictions on motor vehicles, and propose protective measures to the public.

Increased forecasting indicators and difficulty in forecasting

Zhang Xiaoling, deputy director of the Beijing Institute of Urban Meteorology, China Meteorological Administration, said that Beijing is a very large city with a large population and more than 5 million vehicles. Complex underlying surface features, special terrain, urban heat island effects, vehicle exhaust emissions, etc., have had a huge impact on the air quality in Beijing.

According to Zhang Xiaoling, Beijing is located in the northwestern part of the Great Plains of North China, with a total area of ​​approximately 16,800 square kilometers, approximately 62% of mountainous areas, and approximately 38% of plains. Beijing is located in the transitional zone between mountains and plains, north of Jundu Mountain, west of Taihang Mountain in the north, Yanshan Yuzhi in the northeast, and northern Fujian Plain in the east and south. It is surrounded by three mountains, three in the west, north, and northeast. The main peak is 2100-2300 meters above sea level, forming an arc-shaped natural barrier. The central and southeastern parts of the piedmont plains, with a gentle transition to Bohai Bay, are about 100-10 meters above sea level, forming a special terrain with a back-to-back sea surface. The special geographic location and terrain distribution have increased the difficulty of forecasting air quality in Beijing.

Zhang Xiaoling said that with the development of Beijing’s urbanization and the continuous implementation of pollution control measures, some primary pollutants have been significantly reduced in concentration, such as sulfur dioxide, but secondary pollutants (such as ozone and a part of PM2.5) have become difficulties in air pollution control. It has also become the focus and difficulty of air quality forecast. Beijing’s urban population is dense, traffic pollution is serious, and all types of pollution sources have high emission intensity. The diffusion, transformation, transmission, and sedimentation of pollutants in the atmosphere are constrained and affected by meteorological conditions, and the meteorological conditions, diurnal variations of the atmospheric stratification, and seasons Obvious changes have brought great challenges to the accurate prediction of daily changes in pollutants and regional distribution.

“The indicators for air quality forecasting will increase next year, and forecasting will face many new challenges.” Qiu Qihong said that some new indicators have a short history of monitoring, and their pollution laws are not as detailed as old pollutants. For example, for PM2.5, the overall monitoring time in Beijing is still very short, and PM2.5 contains primary pollutants that are directly discharged from pollution sources and secondary pollutants that are generated in the air and are complex in composition. A new forecast method for new pollutants needs to be established, which is not as perfect as it used to be. In addition, many sources of pollution are currently not known in detail.

Meteorological Environmental Protection and Working Together to Improve Forecast Accuracy

“Air quality is affected by many factors such as pollution source emissions and weather changes.” Guo Rui, an engineer at the Beijing Meteorological Observatory, said: “Improve the accuracy of weather forecasting, master the discharge and transmission laws of pollutants, and explore the interplay between air pollution and weather and climate. Relationships are the key to improving the accuracy of air quality forecasting."

Ji Chongping, deputy director of the Beijing Meteorological Observatory, stated that in the 11-year history of air quality forecasting, the Beijing Meteorological Bureau and the Beijing Municipal Environmental Protection Agency have conducted multi-channel and all-round cooperation, such as the establishment of weather conditions, forecasts, and environmental monitoring. Data sharing mechanisms, daily federations, and joint scientific and technological breakthroughs.

According to Ji Chongping, the future meteorological department will carry out more in-depth cooperation with the environmental protection departments: further improve the daily work cooperation mechanism, increase the frequency of federations according to business development needs, and appropriately adjust and refine air quality forecast products; On the basis of the Cooperation Framework Agreement between Beijing Municipal Bureau of Meteorology and Beijing Municipal Bureau of Meteorology, strengthening communication and cooperation, jointly applying for scientific research projects, focusing on PM2.5 forecasting and heavy pollution day early warning, and conducting related research; and strengthening meteorological conditions formed on heavy pollution days. Research and study objective methods for heavy pollution.

At 3 pm on the 13th, the Beijing Municipal Environmental Protection Monitoring Center. The forecasters in the automatic monitoring room were concentrating as usual and began to discuss the air quality changes in the next three days. After obtaining preliminary forecast opinions, the main class Dong Xin and Beijing Meteorological Observatory experts met again. Meteorologists mainly analyzed and judged the impact of meteorological conditions on the spread of air pollutants. At the end both parties jointly confirmed the forecast conclusion: The arrival of cold air on the 16th Previously, atmospheric diffusion conditions did not improve significantly. Soon, their predictions appeared on the Internet, mobile phones, television, and radio.

“We are in the sprint phase before the exam. The pressure is relatively great.” Qiu Qihong told reporters, “We will speed up the preparations. The environmental protection and meteorological departments will also work closely together to make air quality forecasts according to the new standards. Starting from the New Year's Day next year, we will be able to operate smoothly and smoothly, but the difficulty of forecasting is indeed greater, and there will be a process of perfection."

Next post: Red light can not blame the pedestrians to reveal the distribution of road rights deep-seated contradictions
Previous post: Jinan taxi mounted some of the passengers claimed to be suspected of monitoring infringement