Share your views on sandstorms

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Sandstorms are a typical example of nature’s revenge resulting from humans’ excessive exploitation of the natural environment. Human activities such as overfarming and overgrazing lead to the destruction of vegetation, the deterioration of the ecological environment, and a decline in land productivity, turning large areas of fertile land and grasslands into deserts. For example, Ejin Horo Banner in Inner Mongolia has historically been known as the \"Granary of Juyan.\" Once it was a region with abundant water and grass, but now it has become one of the main sources of sandstorms in China; a significant portion of the sand that fills the skies over North China and other areas each year comes from Ejin Horo. One reason for this situation is the increase in population, along with excessive cultivation and grazing, which lead to the destruction of vegetation and grasslands. In areas lacking vegetation protection, soil erosion becomes severe under harsh climate conditions. Secondly, there has been a sharp increase in agricultural water use in the upper reaches of the Ejin River; dams and irrigation channels have diverted the water that should have flowed into the Ejin River to other areas, preventing the downstream ecosystems from receiving enough water. As a result, Lake Ejin turned into a desert, and its cries could be heard throughout North China.

Before the Olympics, some attention was paid to this practice of planting trees by those who came before so that future generations could benefit from them. However, it was only through **orders from local authorities** that such actions were taken; otherwise, they would surely focus on achieving more visible achievements.

It is mainly the decrease in the number of trees, coupled with excessive drought in spring, that leads to frequent sandstorms

It seems to be that fundraising campaign for large-scale afforestation from last year. I don’t understand how so many people could believe it – planting trees in the desert takes at least 20 to 30 years before those trees grow into a forest, and it’s also necessary to ensure that all the plants survive. To hear them claim that benefits can be achieved within a few years or even a decade is simply impossible. If that were the case, there wouldn’t be so many deserts left; they would have turned into oases by now

What is a sandstorm? A sand duststorm is a general term that encompasses both sandstorms and duststorms; it refers to a severe weather phenomenon in which strong winds lift large amounts of sand and dust from the ground into the air, causing the air to become extremely turbid and resulting in a horizontal visibility of less than 1 km. Among them, a sandstorm refers to a storm carrying sand that is formed when strong winds blow large amounts of sand particles into the near-surface layer ； A dust storm is a storm formed when strong winds lift large amounts of dust and other fine particles into the upper atmosphere. Sources and pathways of sand and dust: Sandstorm weather mainly occurs in late spring and early summer. This is because there is very little precipitation in arid regions during winter and spring, resulting in an extremely dry and loose surface that has weak resistance to wind erosion. When strong winds blow, a large amount of sand and dust is lifted into the air, leading to sandstorm conditions. 　　Globally, sandstorms occur frequently in inland desert regions; the main sources of such storms are the Sahara Desert in Africa, the central and western parts of North America, and Australia, which are also among the regions where sandstorms arise. Between 1933 and 1937, severe droughts led to the formation of famous bowl-shaped dust storms in the Midwestern United States. The active centers of sandstorms in Asia are mainly found in the Jordan Desert, Lower Mesopotamia between Baghdad and the northern coasts of the Gulf, the southern Iranian coast near Abbas, and extending to the plain areas in northern Afghanistan. Kazakhstan, Uzbekistan, and Turkmenistan in Central Asia, former parts of the Soviet Union, are all areas frequently affected by sandstorms (≥15 per year), with the epicenters located in the sandy plains between the Caspian Sea and the Aral Sea as well as in the region around the Amu Darya River. Due to its unique geographical conditions, the northwestern region of our country is also a place where sandstorms occur frequently. The main sources of these sandstorms are the Gobi Desert, the Taklamakan Desert, the Badain Jaran Desert, the Tengger Desert, the Ulan Buh Desert, and the Mu Us Desert, among others. Causes and physical mechanisms of sandstorm weather. The causes of sandstorm weather: Weather conditions that facilitate strong winds, an appropriate distribution of sand and dust sources, and conditions of air instability are the main factors behind the formation of sandstorms or severe sandstorms. Strong winds are the driving force behind sandstorms; sand and dust serve as the material basis for these storms. Unstable thermal conditions facilitate increased wind speeds and stronger convection, which in turn carries more sand and dust and lifts it higher into the air. 　　In addition, the previous period of drought and low rainfall, along with warming weather and rising temperatures, constitute the specific weather and climatic conditions that give rise to sandstorms ； Small- to medium-scale systems in which convective cells ahead of surface cold fronts develop into cloud clusters or squall lines are conducive to the development and intensification of sandstorms ； The topographical condition that facilitates an increase in wind speed, namely the effect of a narrow channel, is one of the favorable conditions for the formation of sandstorms. 　　Physical mechanisms of dust storm formation: Under highly favorable large-scale environmental conditions, such as dry and cold upper-level jets, strong vertical wind speeds, wind direction shear, and thermally unstable stratification, small- to medium-scale systems form and develop near the front zone. This leads to an intensification of the pressure and temperature gradients before and behind the front zone, resulting in significant pressure-temperature gradients in those areas. Under the combined effect of downward momentum transfer and gradient wind bias, wind speeds in the near-surface layer increase sharply, lifting sand and dust from the ground and resulting in sandstorms or severe sandstorm conditions. 　　Main ways sandstorms cause harm: ⑴ Strong winds: Strong winds carrying fine sand and dust destroy buildings and public facilities, leading to deaths of people and animals. 　　⑵ Sand burial: It occurs when wind and sand currents cause farmlands, canals, villages, railways, grasslands, etc. to be covered by large amounts of sand, posing a serious threat especially to transportation. 　　⑶ Soil wind erosion: The source areas and affected regions of each sandstorm suffer from wind erosion to varying degrees, with the depth of erosion ranging from 1 to 10 centimeters. It is estimated that China loses as much as 106–107 tons of fine soil particles each year due to sandstorms; the vast majority of these particles have a size of less than 10 microns, causing severe damage to the land productivity of farmlands and grasslands in the source areas. 　　⑷ Air pollution: In the areas where sandstorms originate and in their affected regions, the level of inhalable particulates (TSP) in the air increases, leading to greater air pollution. Taking the severe sandstorm on May 5, 1993, as an example, the TSP concentration in the outdoor air of Jinchang City in Gansu Province reached 1,016 mg/m3, while it was 80 mg/m3 indoors, which is 40 times higher than the **standard. In March and April 2000, the Beijing area was affected by sandstorms; the air pollution index reached level 4 or higher for 10 days, and this also impacted many cities in eastern China. From March 24 to 30, the daily pollution index in 18 cities, including Nanjing and Hangzhou, exceeded level 4. 　　The harms of black winds 　　The harms of black winds can be summarized in two words: wind and sand. 　　The harms of strong winds are also two-fold: one is wind-induced damage, and the other is erosion of the land surface. 　　Let’s talk about wind damage first. Strong winds damage buildings, knock down or uproot trees and utility poles, and tear apart farmers’ plastic greenhouses and agricultural plastic films, among other things. Furthermore, in the northwest region, April and May are the periods when cash crops such as fruits, vegetables, beets, and cotton emerge, grow their cotyledons or true leaves, and fruit trees bloom; it is during these times that they are most vulnerable to wind and sand. In mild cases, the leaves get dusty, which reduces photosynthesis and affects respiration, thereby lowering crop yields ； In severe cases, the seedlings die and the flowers wither, leaving no chance of mature fruit formation. For example, on May 5, 993, a violent wind destroyed the stamens of 85,000 fruit trees in the northwest region, and caused 109,400 trees in shelter forests and timber forests to break or be uprooted. In addition, strong winds knocked down power poles, resulting in water and electricity outages that affected industrial and agricultural production. The power and water outages caused by the black wind on May 5, 1993, resulted in economic losses of 83 million yuan alone for Jinchuan Company in Jinchang City. 　　When strong winds affect the loose soil in arid areas, they can scrape away a layer of the topsoil, a phenomenon known as wind erosion. For example, on May 5, 1993, the average wind erosion depth was 10 centimeters (up to 50 centimeters), which means that on average 60 to 70 cubic meters of fertile topsoil were blown away per mu of land. In fact, strong winds not only blow away the fine clay and organic matter in the soil, but they also deposit sand in it, significantly reducing the soil’s fertility. Furthermore, strong winds carrying sand particles can wear away a layer from the surfaces of buildings and crops; this phenomenon is known as abrasion, and it is also a type of disaster. 　　The main hazard of sand is sand burial. As mentioned earlier, in areas such as narrow channels, windward slopes, and raised terrain, where wind speeds are high, the main hazard caused by wind and sand is wind erosion; whereas in shaded and low-lying areas where wind speeds are lower, the main hazard is sand burial. For example, at the site where sand burial occurred during the black wind on May 5, 1993, the average thickness of the sand layer was 20 centimeters, with the thickest areas reaching 1.2 meters. 　　Furthermore, and more importantly, there is the loss of human lives. For example, on May 5, 1993, the Black Wind disaster caused 85 deaths, 264 injuries, and 31 people went missing. In addition, 120,000 head of large livestock died or were lost, 5.6 million mu of crops were damaged, water channels that serve as lifelines in the drought-stricken areas totaled over 2,000 kilometers in length, and the Lanzhou-Xinjiang Railway was shut down for 31 hours. The total economic loss exceeded 540 million yuan.

It is only possible to start by addressing the source of the dust, thereby eliminating the dust sources. This is a huge project that requires **investment to be completed.

The land has become desertified, leading to sandstorms. It is mainly by afforestation to retain soil moisture that the area affected by desertification can be reduced.

Although most people believe that sandstorms are a form of nature’s revenge on us for our excessive deforestation and environmental destruction, some scholars argue that they represent a mechanism of self-regulation in nature; interfering with sandstorms artificially would therefore be a sign of disrespect toward nature. At present, sandstorms are definitely not good for us; they are harmful to our health. However, it still needs to be studied to determine whether they are beneficial to the environment.

It’s mainly a water issue: first, excessive extraction of groundwater leads to a drop in the water table, preventing grass and trees from getting enough water and causing them to die naturally. Second, as the friend upstairs mentioned, excessive water use in the upstream sections of the river affects the downstream areas. To manage projects that use industrial water, the administrative authorities should develop proper water usage plans.

A significant factor is the drop in water levels; back in the 1970s, we just had to dig a hole there, and after a few days we could draw water to use for drinking. Now we have to drill wells that are over thirty meters deep just to get access to water, and the water in the wells surrounding a puddle in our village has become salty. There is also more sand and dust than before. We strongly urge **to intensify tree planting in order to restore a safe living environment for us!** ! !

In 1993, eastern Xinjiang, the Hexi region of Gansu, most of Ningxia, and the western part of Inner Mongolia were affected. In 1998, the central and western parts of Inner Mongolia, the southwestern part of Ningxia, and the Hexi Corridor in Gansu were hit by severe sandstorms; the impact was widespread, reaching places such as Beijing, Jinan, Nanjing, and Hangzhou. In 1998, the northern and eastern parts of Xinjiang, including the Tushan Basin, were struck by winds with speeds of up to level 12, and sandstorms also occurred in some areas. This severe storm disaster caused extensive property damage, with 6 deaths, 44 people missing, and 256 injuries. In the early hours of May 19, northern Xinjiang was struck by strong winds; in areas such as Alashankou and Tacheng, the wind strength reached level 9 to 10, with instantaneous wind speeds of 32 meters per second. In other areas, the wind strength was generally at level 6 to 7. Strong winds knocked down large trees, and power lines were severed in some areas. 1999: From April 3 to 4, Hohhot region experienced continuous strong winds and sandstorms for two days in a row. The scope of this dust storm extended from the western part of the Inner Mongolia Autonomous Region to the southern part of Tongliao City in the east, with instantaneous wind speeds of 16 meters per second. The wind speed in Dalarat Banner of Ikzhao League reached up to force 10. 2000: From March 22 to 23, severe sandstorms struck the Inner Mongolia Autonomous Region; some of the sand was carried by strong winds to the area over Beijing, exacerbating the sandstorm conditions there. On March 27, a sandstorm struck Beijing once again, with wind speeds reaching 8 to 9 on the scale in some areas. Seven workers working on the roof of a two-story building in the Anxiangli residential complex were blown down by strong winds, with two of them dying on the spot. Some billboards were blown down by strong winds, injuring pedestrians and damaging vehicles. 2002: From March 18 to 21, the largest, strongest, most severe, and longest-lasting dust storm event since the 1990s struck over 1.4 million square kilometers in northern China, affecting a population of 130 million people.

In March 2002, I experienced a sandstorm in Beijing; fortunately, I went to the coastal areas of Shandong not long after that. It doesn’t have much severe weather to worry about; at least people can leave whenever they want.

The weather forecast says it’s going to rain dust in Lanzhou again today.

Against the backdrop of global warming, the temperature in northern China rises faster than in the south. The pressure difference between the north and south is decreasing, leading to fewer strong winds and, as a result, less dust storm activity. The relevant monitoring results also confirm the same conclusion: the frequency of dust storms has decreased significantly compared to the 1950s. But the most important factor is the continuous expansion of sand sources. Specifically, on one hand, it is necessary to plant trees and grass scientifically, especially in the areas where sandstorms originate, in order to carry out afforestation there. Taking Beijing as an example, most of the sandstorms affecting it originate from other areas; planting trees only in the vicinity of cities like Beijing is not enough to prevent sandstorms – what’s important is to address the sources of these sandstorms. On the other hand, in areas with fragile ecological conditions such as the northwest, reasonable agricultural production methods should be adopted to consolidate the achievements of converting farmland back into forests and reduce human impact on the ecological environment. Only by allowing the fragile surface environment to recover gradually can the occurrence of sandstorms be reduced.

The simplest way is to plant more trees and grass! But this requires **to step in

Adhere to scientific development, quickly make amends for the past overexploitation of nature, plant trees, and practice soil and water conservation.