The worst season for air pollution is coming soon. Is the haze coming from the north?

This past weekend, Hangzhou, Jiaxing, and other areas in central and northern Zhejiang suffered from the most severe haze since this autumn. On the 1st, the China Meteorological Administration announced that since the beginning of this year, 13 provinces and cities, including Zhejiang, have had the most smog days in the same period in history. The most terrible thing is that winter begins this Thursday, and the season with the heaviest air pollution is coming.

Tian Xudong, a senior engineer at the Provincial Environmental Protection Department Testing Center, predicts that the air pollution situation in our province this winter will not be much different from last year, which means that the air quality will hardly improve. AQI is the abbreviation of Ambient Air Quality Index. It is a new air quality evaluation standard released by the country in March 2012. There are 6 pollutants monitored: sulfur dioxide, nitrogen dioxide, PM10, PM2.5, carbon monoxide and ozone. The data is updated every hour. once. AQI presents these six pollutants using unified evaluation standards.

Shaoxing and Zhuji AQI are severely polluted

If you own a high-rise residence with a wide view in Hangzhou, you will definitely see this scenery in front of the window in the past two days - the sky and the earth are like a piece of cake. It's dark, and the tall buildings hide in the haze. Because I am worried about the dirty particulate matter mixed in the air, which will disrupt my travel plans or mood. Such hazy weather will inevitably make people sigh.

At 5 pm yesterday, the environmental quality data release platform page of the Provincial Environmental Protection Department website showed that the air quality index (AQI) in most areas of the central and northern parts of the province was upwards of 100, which is above mild pollution. The testing sites in Quzhou, Pujiang, Shangyu, and Shaoxing cities reached moderate pollution, while the AQIs of Shaoxing County Government and Zhuji City Transportation Management Office were 214 and 218 respectively, reaching severe pollution.

Except for the two testing stations in Xixi and Yunqi, the air quality in Hangzhou was good, while the rest were lightly polluted.

The air quality is excellent (AQI is lower than 50), concentrated in Zhoushan, Taizhou, Wenzhou, southern Lishui and other areas.

But looking across the country, the haze in Zhejiang is still mild.

Compared to Beijing, Tianjin, Hebei and other places that are 1,000 kilometers away from us in a straight line, they are experiencing heavy smog attacks. Alarms have been sounded in various places. For example, in Beijing yesterday, the PM2.5 concentration reached Level 5 severe pollution levels. There is a joke on the Internet that the visibility in Beijing is only 5-6 meters, and the bus driver does not even know if he is driving in the wrong direction.

Why are many places in central and northern Zhejiang shrouded in haze

According to the Zhejiang Provincial Meteorological Observatory, the culprit of the recent gray skies is fog. On the night of the 2nd, rainfall occurred across the province, increasing the humidity of the air near the ground. In the morning after a rain, the sky is cloudless and windless, so the chance of fog is very high.

Fog itself is not pollution, but under such stable conditions, pollutants in the air are not easy to diffuse outwards and can easily cause agglomeration effects. In addition, the recent cold air performance is "poor" and it is not coming. Harassment, the weather situation is calm, the temperature has risen again, and the "dirty things" in the air cannot be blown away in time, making the air pollution more and more serious, and many places in central and northern Zhejiang are shrouded in haze.

Tian Xudong also attributed the recent air pollution to weather diffusion conditions. Zhejiang is currently in the transition period between autumn and winter. Before the cold air comes, there is no wind, the air is still, and the humidity is high, which can easily form haze. Resulting in poor air quality.

He said that if cold air comes or rains in the near future, air pollution can be effectively reduced.

According to the forecast of the China Meteorological Administration, in early November, it will still be difficult for the central and eastern regions to completely get rid of the haze.

Zhejiang has the most smog days in the same period in history

According to the China Meteorological Administration, the national average number of smog days is the highest since 1961. Zhejiang, Hebei, Tianjin, Jiangsu, Anhui, etc. Provinces and cities have recorded the highest number in the same period in history.

Since October, it has been 10-15 days in central and northern Zhejiang, Henan, Jiangsu, northern Anhui, Beijing, Tianjin and other places; 15-20 days in southeastern Shanxi, most of Henan, and most of Jiangsu , more than 20 days in some areas.

Compared with the same period in normal years, the number of haze days in central Zhejiang, southern Hunan, Beijing, Tianjin and other places was 5-10 more; among them, northern Jiangsu, central Henan and other places had more than 10 more haze days, and some areas More than 15 days.

From December to January last winter, Zhejiang experienced frequent smog days and heavy air pollution. How is it going this year? Tian Xudong said that since last year, PM2.5 and other air quality issues have attracted great attention from society, and the government is also making great efforts to control pollution. But he believes that the air quality in our province this winter will not be much different from last year.

He pointed out that air pollution is caused by climate, industrial pollution emissions, vehicle exhaust and other factors. Air pollution control is a long-term process. In the context of climate change, annual air quality changes are relatively small. Small. In winter, the diffusion conditions of pollutants are poor, the temperature is low, the vertical diffusion height of the atmosphere is relatively low, and the space for diluting pollutants is relatively small.

Is the smog coming from the north?

Haze and fog are very similar, they are meteorological brothers. A moisture content of more than 90% is called fog, and a moisture content of less than 80% is called haze.

Zhejiang is prone to smog in autumn and winter. The main reason is that atmospheric diffusion conditions are very poor during this season. In addition, regardless of the size of a city, the pollutant emissions from the energy consumption required for local transportation, life, and production are constantly accumulating at low altitudes.

There is more and more smog in Zhejiang. Is it coming from the north?

Tian Xudong believes that there is a certain relationship and does not rule out the possibility of air pollutants from the north spreading to Zhejiang through atmospheric transport. As the seasons change, the northwest wind increases, which means that pollutants may also spread from north to south as the cold air moves southward.

The person in charge of the Provincial Meteorological Observatory said that a qualitative answer cannot yet be obtained. Because we need to pay attention to a rigorous scientific attitude, this requires the sum of various observation elements and indicators, which is a scientific research topic, and there must be enough time to accumulate. Yesterday, the most popular item sold in the small commodity area of ??Keqiao Clothing Market in Shaoxing was masks.

“Before closing the stall, hundreds of masks have been sold out.” Ms. Wang, the stall owner, said that customers who come to buy masks don’t ask her which mask is better at keeping warm, unlike before. Which one is better at blocking dust?

On the shelves of each stall, there are three categories: medical disposable masks, gauze masks and cotton cartoon masks. Among them, gauze masks are divided into two categories: sterilized and non-sterilized, with 10, 15, 20 and other layers.

Ms. Wang, the stall owner, said that among the three types of masks, the best-selling ones are non-sterile ordinary gauze masks. The more layers, the better the protective effect. They are suitable for people who spend a long time in the open air and can block Dust, pollen, etc. in the air. Sold in packs of ten, priced between 15-20 yuan.

The sales of cotton cartoon masks are relatively poor. They block dust with larger particles and are more beautiful to wear.

There was a sign hanging at a stall that read "To prevent haze, buy PM2.5 special masks." The stall owner, Boss Luo, said that the PM2.5 special masks he sells have activated carbon filters and three layers of high-efficiency filter cloth. They cost 38 yuan each and can sell forty or fifty masks a day. He also thought about purchasing N95 masks, but the purchase price was high, so he did not purchase them.

In Yiwu Futian Market, there are more than 100 shops specializing in masks.

“The production process of protective masks is relatively complicated, and the defective rate is relatively high. Originally, manufacturers were unwilling to do it, but now they can’t handle the booming business and are following up.” Mr. Chen, who has been in the mask business for 4 years , this year imported more than 100 types of protective masks from Guangdong.

He used to make thermal masks, and his business was average. Now he has switched to protective masks, and many wholesalers have come to him. "There are many wholesalers from the north and people who open online stores."

Yesterday at 4:23 pm, Yiwu Futian Market was about to close, but Ms. Xu was still receiving two Taobao stores. The sales situation of protective masks can be described as a "blowout".

She roughly calculated the sales of the day. In Beijing and Shijiazhuang, more than 30,000 were sold in one day. "The other party said on the phone that they will send as many as they have."

Xiao Li, who runs an online store in Qingkou, Yiwu, arrived at Ms. Xu’s store at 2 p.m. and waited until 4 p.m. to get 1,000 masks. "I make household products, and now I mainly promote masks."

Xiao Li opened his Taobao store and checked "Sold Items". "I can earn at least two thousand a day just by selling protective masks."< /p>

In the market, there are about 10 shops selling protective masks. I visited 6 of them, and they usually have a brand, and the packaging bag is marked with the production date, manufacturer, etc.

However, there are many problems with the sophisticated protective mask filter materials.

The proprietress of a shop said that the protective masks were made in her factory, and the non-filter sheets were imported from Guangzhou. “I don’t know what material it is made of, and it’s not written in the instruction manual. The factory says it has the effect of protecting PM2.5.

”

According to the protective mask filters currently on the market, the material generally says “activated carbon filter”. There are also some filters that claim to have a filtration performance of over 99%, but they do not explain what they are used for. What material is it made of?

Boss Zhang, who has been in the mask business for many years, said, “There are some stores on the market that sell protective masks in the past, but they only made clothes in the early years, and the performance of the filters varies. I don’t know if those masks are useful. ”

The air quality is satisfactory and there is basically no air pollution; all types of people can carry out normal activities. Shaoxing protective masks are sold out. The air quality in Yiwu is acceptable, but some pollutants may be harmful to the health of a very small number of extremely sensitive people. Weak impact; a very small number of extremely sensitive people should reduce outdoor activities Beijing Shijiazhuang Customers

How many masks are needed? Susceptible people have mildly aggravated symptoms, and healthy people have irritating symptoms; children, the elderly and people with heart disease , Patients with respiratory diseases should reduce long-term, high-intensity outdoor exercise, which will further aggravate the symptoms of susceptible people and may have an impact on the heart and respiratory systems of healthy people; children, the elderly and patients with heart disease and respiratory diseases should avoid long-term, high-intensity exercise Intense outdoor exercise, the general population should moderately reduce outdoor exercise. Symptoms of patients with heart disease and lung disease are significantly aggravated, exercise tolerance is reduced, and symptoms are common in healthy people; children, the elderly, and patients with heart disease and lung disease should stay indoors and stop outdoor exercise. , the general population should reduce outdoor exercise. Healthy people have reduced exercise tolerance, have obvious and strong symptoms, and develop certain diseases in advance; children, the elderly and patients should stay indoors to avoid physical exertion, and the general population should avoid outdoor activities