Starting from the afternoon of April 25, large-scale sand and dust weather once again affected many parts of our country!
At present, sand or floating dust weather has occurred in central and western Gansu and western Inner Mongolia, and sandstorms have occurred locally in Zhangye, Gansu and Alxa League in Inner Mongolia.
From the night of the 26th to the day of the 27th, the Beijing-Tianjin-Hebei region will also experience sand or floating dust.
The Central Meteorological Observatory continues to issue sand and dust storm warnings.
This year, North China has encountered 5 large-scale sand and dust weather processes.
Why does the sand and dust weather come round after round this year?
What impact will this dusty weather have on our country?
A reporter from Lantian Studio interviewed experts from the Central Meteorological Observatory to explain in detail the causes and effects of sand and dust.
The Central Meteorological Observatory issued a blue warning for sand and dust storms
Gui Hailin, chief forecaster of the Central Meteorological Observatory, introduced that affected by strong cold air, it is expected that from 20: 00 on the 26th to 20: 00 on the 27th, eastern Xinjiang and southern Xinjiang basin, northwestern Qinghai, most of Inner Mongolia, central and western Gansu, Ningxia, Shaanxi Some areas in the north, Shanxi, Hebei, Beijing, Tianjin, central and western Shandong, northern Henan, northern Jiangsu and Anhui, southwest Heilongjiang, western Jilin, western Liaoning and other places will experience sand or floating dust weather. Among them, central and northern Inner Mongolia is local There is a sandstorm.
The Central Meteorological Observatory has continued to issue blue dust storm warnings at 18:00 on the 26th.
The Beijing Meteorological Bureau predicts that there will be strong winds and dust in Beijing from midnight on the 26th to daytime on the 27th.
The Beijing Meteorological Bureau pointed out that due to the impact of cold air and upstream sand and dust transportation, it is expected that sand and dust weather will appear in Beijing from the middle of the night on the 26th, with a minimum visibility of 3 to 5 kilometers.
On the morning of the 27th, the northerly wind gradually increased to magnitude 4 and 5, and gusts could reach around magnitude 7.
On the afternoon of the 27th, the sand and dust gradually weakened, and the wind decreased around the evening, and the dust weather basically ended.
In response to this weather process, the Beijing Meteorological Observatory issued a blue early warning signal for gale and blue sand and dust at 10:30 on the 26th.
The Beijing Meteorological Bureau stated that due to the higher soil humidity in the upper reaches than in March, and the presence of precipitation from the night of the 25th to the 26th in Inner Mongolia, the inhibitory effect on the sand and dust was obvious. The intensity of the sand and dust was significantly weaker than that on March 15 and 3. On the 28th and 15th of April, the three sand and dust weather processes.
Meteorological experts reminded that during the dusty weather, close doors and windows to reduce going out, especially the elderly, children and people with respiratory allergic diseases.
When you must go out, please wear masks, gauze and other dust-proof products for protection.
Drivers should slow down and drive cautiously when driving;
The weather is dry and dry in windy weather, so you should pay attention to wind and fire prevention, and it is strictly forbidden to use fire in the wild to avoid forest fires;
Relevant departments should do a good job in the reinforcement of outdoor structures and billboards, and safety protection for outdoor high-altitude operations.
The public should stay away from tall buildings, billboards, and temporary structures, and beware of falling objects from high altitudes.
How strong is the dust weather this time?
What is the cause?
Gui Hailin said that in terms of the intensity and scope of sand and dust, the sand and dust weather this time was significantly weaker than the previous one (April 15).
The reason is that the Mongolian cyclone is located to the east, and the movement path did not pass through a large-scale sand source, and the material basis is insufficient; secondly, the intensity of the cold air in and behind the Mongolian cyclone is weak, and the large-scale strong wind cannot smoothly remove the sand. The dust blows off the ground and is transported to higher altitudes, that is, the driving force of the dust is insufficient.
"The main cause of the sand and dust weather is still the Mongolian cyclone, but due to the difference in the strength, location, and movement path of the weather system, the intensity and scope of the sand and dust are generally weaker than the previous one," said Gui Hailin.
Desertification is a global problem and requires joint governance by all countries in the world
Since 2021, my country's North China region has encountered 5 large-scale sand and dust weather processes.
Gui Hailin said that there are a lot of deserts, Gobi and other arid and semi-arid surfaces in Central Asia.
In the spring, the temperature in the northern region rises, the surface is thawed, the soil is loose, and the geographical environment meets the conditions for sand and dust.
North China is adjacent to the arid and semi-arid regions of Central Asia. The sources of sand and dust mainly originate from these areas. When there are strong cyclones or strong cold air in the north that bring gale weather systems, when passing through the source of sand, it will cause strong winds To cover the sky and the sun's dusty weather.
Gui Hailin said that from statistical data, spring is the most frequent season of sand and dust (March to May), accounting for almost 60% to 70% of the whole year.
From the perspective of the climate background, the cold and warm air in spring is active, and it is easy to form strong frontal cyclones, which often bring windy weather. In addition, the surface of the sand source in spring is thawed and the surface soil is loose. Under the action of strong winds, it is easy to remove the surface. The soil or sand blows up, forming a dusty weather.
Why does the public feel that sandstorms are more frequent and more intense this year than in previous years?
Will frequent sandstorms hitting the north become the norm in the future?
"Generally speaking, since mid-to-late February in Mongolia and my country's Inner Mongolia area this spring, the temperature has continued to be high and the precipitation has been relatively low; in addition, since March, cyclone activity has increased significantly, and the cyclone and its trailing cold air path have positively affected North China. In the region, the distance from the source of sand to North China is short. Almost every time the sand and dust has a significant impact on the Beijing-Tianjin-Hebei region, everyone feels that this year there will be a lot of sand and dust with great intensity." Gui Hailin said.
Gui Hailin believes that sand and dust weather is actually a normal weather phenomenon in spring, and its amount is related to the specific weather system and underlying surface conditions.
After the global warming, the temperature rise and the decrease of precipitation are conducive to the development of desertification, so in this sense, it is conducive to the increase of sand and dust.
"In recent years, my country's desertification prevention and control has achieved remarkable results. However, desertification is a global problem that requires the joint management of all countries in the world, and the overall ecological environment has been significantly improved in order to effectively reduce its frequency and intensity." Gui Hailin emphasized.
(People's Daily Central Kitchen·Blue Sky Studio)
People's Daily Client Liu Yi