Shulou(Shulou.com)11/24 Report--

This article comes from the official account of Wechat: Earth knowledge Bureau (ID:diqiuzhishiju), author: Demetri, revised manuscript: gu Hanying / Editor: bumblebee

The original title: "Yellow, how serious is the problem in Mongolia?" "

When I woke up this morning, I found that everything outside the window was yellow, as if on Mars. There is no doubt that the sandstorm is coming again.

The Central Meteorological Observatory has issued a yellow warning for sandstorms. Under the influence of an omnipotent cold air, from last night to today, sandstorms basically covered most of the northern areas, and dust will occur successively in the northwest, North China, the central and western parts of the northeast, and Huang-Huai.

The main body of sand and dust will pass through Beijing, Tianjin, Hebei and surrounding areas on the evening of the 22nd. Due to the influence of systematic precipitation process in southern China, the influence of sand and dust process on the south of Huaihe River is limited. The influence of this dust process is expected to weaken and come to an end during the day tomorrow.

The affected area is too large, ▼.

When the sandstorm came, people began to trace the source. Through satellite remote sensing, it was found that the sand transported with the airstream was not made in China. The source of the sand was located in the Gobi Desert in southern Mongolia. With the significant warming of temperature, the sand source land is thawed ahead of time, but the precipitation in the same period is less, and the vegetation can not grow out, which leads to the bare sand on the surface.

As the cold front passes through the sand source, the gale near the surface carries a large number of particles to the southeast, causing sand and dust weather to spread to most parts of northern China.

The recent frequent sandstorms have lifted the veil of environmental deterioration in Mongolia: in recent decades, climate change and man-made destruction have led to widespread desertification, soil erosion, air pollution and other problems.

Day and night in Ulaanbaatar: yellow

For environmental meteorologists, it is not unusual for China's sandstorms to originate from Mongolia. Southern Mongolia has always been an important source of sandstorms in China.

Mongolia is a country of middle and high latitudes established on the grasslands of Neiya. Geographically, the whole country lives inland and is far away from the sea, which means that its land is located in temperate continental climate zone. The moist air mass from the Pacific Ocean is difficult to cross the Daxing'an Mountains from east to west, and the water vapor from the Arctic Ocean is also difficult to reach the south of Hangai Mountain, so the arid Gobi Desert is formed in southern Mongolia.

Pacific water vapor is basically trapped in the second staircase.

A small amount of water vapor from the Arctic Ocean is trapped in ▼ in northern Mongolia.

The area of land vulnerable to desertification accounts for 90% of the country's territory. Only some areas of the northernmost provinces of Kusugur and Kent are immune from land desertification, and it can be said that the desert steppe landscape has spread all over the country.

A country built on desert steppe

It is also a country easily engulfed by desertification.

The vegetation cover in Mongolia can be divided into a simple and rough division according to geographical location, that is, it is getting more and more dry from northeast to southwest. The northeastern provinces of Kent and Orientale continue the charm of the Hulunbuir grassland, and are more affected by the monsoon than other places in summer. The Kruen River and the Onon River flow from west to east and flow into China's Hulun Lake and the Erguna River on the Sino-Russian border, respectively, adding a lot of green to the land along the bank.

By contrast, the south is a vast desert Gobi. This can also be seen from the naming of Mongolian provinces, the three provinces in the south-central part are East Gobi Province, Central Gobi Province and South Gobi Province, and the southwest is also Gobi Altai Province. Three of the four arid provinces are directly bordered by China's Inner Mongolia Autonomous region.

The northeastern provinces are fine.

In the south is the naked Gobi province ▼.

This is where our sandstorms form.

The main cause of desertification in southern Mongolia is the natural cause, which is first attributed to its climatic characteristics. The national average precipitation in Mongolia is about 230mm, compared with the annual average precipitation in China, which is about 560mm.

In this way, the distribution of relatively low precipitation is still extremely uneven. The annual precipitation in the north of Mongolia is slightly higher than that of 500mm, while the annual precipitation in the south is less than 50mm, a gap of more than ten times.

There is still a lot of snow in the north (part I)

And then form rivers and cultivate forests.

The south is completely covered with yellow sand (part two)

(figure: NASA) ▼

When we talk about the impact of precipitation on a region, we have to consider evaporation. Snow-capped and ice-covered Antarctica does not look dry but has one of the lowest precipitation in the world. In Mongolia, about 90% of the precipitation is evaporated back into the atmosphere, with only 10% left.

Of this 10%, 63% of the precipitation will become surface runoff. Mongolia is a landlocked country with high terrain, so 95% of the water in the river flows out of the country and cannot be used as a supplement to water resources.

Not far to the north is Lake Baikal, the freshwater lake with the largest water storage capacity.

Unfortunately, this is Russian territory.

(figure: NASA) ▼

After all, only about 3% of the poor annual precipitation seeps into the soil to replenish groundwater, and most of them exist in the form of soil water or phreatic water, that is, the so-called "potential water resources". Can not be directly used by surface organisms.

As a result, the surface soil and rocks in the arid areas of the south are basically bare, that is, barren land. This bare land is the Gobi, which is a word derived from Mongolian and refers only to the arid lands of Central Asia, Mongolia and Northwest China.

Gobi is a unique type between China and Mongolia.

Most of these areas are not deserts but bare rocks.

The surface shape of the Gobi makes it easy for solar radiation to affect the surface rocks, and the temperature and climate change in Mongolia are extremely severe. The maximum daily temperature difference is 30 ℃, the average annual temperature difference in winter and summer is huge, and the annual temperature difference in some areas is close to the extreme 90 ℃. For example, the area around Ulaanbaatar reaches-60 ℃ in winter due to extremely low temperatures and 30 ℃ in summer due to strong sunshine and urban heat island effect.

Perfectly matches the characteristics of temperate continental climate.

Drought and storm are the two major natural disasters in Mongolia ▼

Extreme temperature differences create extreme natural landscapes, and rocks are constantly broken and broken during thousands of years of weathering. The average wind speed in the Gobi area of Mongolia is between 3m / s and 4m / s, and the fine sand and gravel are polished by strong winds near the ground, which is the source of sand in the desert.

Gobi Desert of Mongolia

(figure: Richard Mortel / Wiki) ▼

The hillside climate full of cattle and sheep makes Mongolia's natural environment extremely fragile and vulnerable to human activities.

Mongolia is a country with more sheep than people. More than 3 million people are raised on 1.57 million square kilometers of land, while cattle, sheep and other livestock and wild animals are more than 66 million.

Animal husbandry is the pillar industry of Mongolia

Most meat is exported to China and Russia.

Overgrazing is an important cause of desertification in Mongolia, and it is also one of the biggest human factors. According to official statistics in 1998, there were 31.3 million livestock in 18360 households in Mongolia. This greatly increases the pressure on prairie pastures.

In fact, there have been grassland peoples in the Mongolian plateau for thousands of years, and there have been herdsmen grazing cattle and sheep, so why do the bad consequences only appear in recent decades? This is because of the change in the grassland way of life.

Compared to the time of existence of Mongolia

The history of grazing on this plateau is much longer.

(figure: Wiki) ▼

In the past, the grassland people lived a nomadic life of living after water and grass, and every once in a while they changed a piece of grassland to graze, which achieved the effect of letting the grassland rest in rotation. Before and after the second World War, Mongolia was deeply influenced by the Soviet Union and absorbed the experience of Soviet-style "collective farms".

This change is multifaceted. First of all, it is reflected in the way of living and life. herdsmen who are used to living without fixed abode have to settle on a piece of land and are not allowed to change their dwellings and pastoral areas. Secondly, in the mode of production, the grassland is divided into one piece of pasture after another, each of which has its own production unit, in which herdsmen carry out collective labor.

Settling down has improved the living conditions of the herdsmen.

But the formulation of policies should also take into account the laws of nature.

This puts great pressure on the grasslands, and there is no rest for grazing year after year. And under the guidance of erroneous ideas at that time, people blindly pursued high yield, the herd expanded disorderly, and the contradiction between more cattle and sheep and weaker pastures became more acute, resulting in the destruction of the environment.

If you gnaw on a piece of ground, you'll be bald.

From another point of view, in fact, the environmental carrying capacity of temperate desert areas is very limited, soil and climate limit the development of local production, is not a suitable area for human habitation. From ancient times to the present, the population of grassland ethnic groups has a bottleneck, reaching an extreme value will decline. At the beginning of the founding of Mongolia, there were a total of 700000 people, still struggling on the line of subsistence. Today, due to the advent of the industrial age and the development of medical care, the population of this country has reached 3.2 million.

The population of more than 3 million does not seem to be large.

The main reason is that Mongolia's economic pillar eats too much on the advantage of resources.

More people need more material to support, and Mongolia's two pillar industries, mining and animal husbandry, are extremely destructive to the environment. With the passage of time, especially in the past 30 years, the deterioration of the country's environment shows an irreversible trend, and the degree of desertification increases day by day.

Mongolia has 1/10 of the world's known coal reserves.

Most mines are open-air.

This in itself is a major cause of pollution.

The current situation of desertification in night Mongolia in Ulaanbaatar is caused by a variety of factors. In addition to the most important overgrazing, the development of mining and farming has also had a negative impact on the environment.

Water is a precious resource in this country, and the hydrological conditions of many rivers in Mongolia have deteriorated over the past few decades due to the extensive use of irrigation and mining. Including but not limited to falling water levels, river drying up and water pollution, and so on.

Shortage of water resources caused by climate change and blindly pursuing economic development

It not only affects animal husbandry, but also threatens the water use of residents.

In the driest southern region of the country, for example, Lake Wulan and Lake Orog, which used to nurture civilization and water plants, have almost completely dried up. Although some rivers still exist, they have also been seriously affected and their vitality has been greatly reduced. The Tule River, located in the central province, for example, has an average annual flow of 32% less than it did in the 1970s. The main reason is that 270 square kilometers of forest in the Tule River Basin was cut down for development reasons in the last century, which greatly aggravated the problem of soil and water loss in the basin.

Wulan Lake, once one of the five major lakes in the Gobi region

In the late 20th century, the gold mining program began to dry up.

(figure: tourism.omnogovi.gov.mn) ▼

The Tule River is one of the most typical examples of man-made damage to nature in Mongolia. As the most sparsely populated country in the world, Mongolia does not have much ability and necessity to transform nature on a large scale. As an isolated event, the problem of the Tule River Basin is behind the severe environment of the capital Ulaanbaatar.

The Tule River, which rises in the Kent Mountains, flows south of Ulaanbaatar.

It is one of the important water sources in its territory.

One of the most sparsely populated countries has a capital with extremely high population density. The city of Ulaanbaatar has a population of more than 1.5 million, equivalent to half of the country's total population. The capital and other areas seem to be two countries. The urban landscape of Ulaanbaatar is relatively perfect and high-rise buildings are busy, in sharp contrast to the desolation and backwardness of most parts of the country.

Mongolia is divided into two places, Ulaanbaatar and others

In order to maintain the operation of the huge city of the capital, the surrounding trees have basically been cut down. As a continuation of the idea of Soviet-style industrial city construction in the last century, the urban pollution of Ulaanbaatar is very serious, with uncontrolled discharge of industrial waste water, coupled with the exhaust of vehicles, and the neglect of greening in the period of urban planning. the air quality in Ulaanbaatar is already at a relatively low level. Every year at the turn of spring and summer, blowing sand and dust weather is also common for local residents.

Ulaanbaatar has been rated as "the place with the dirtiest air in the world" by the media many times.

Perhaps the most serious problem for Mongolia is that the deterioration of the environment has yet to take a turn for the better. On the one hand, global warming makes extreme weather appear more frequently, as shown in the Gobi region of Mongolia, where higher and higher temperature differences aggravate desertification, and more and more grasslands become Gobi desert. On the other hand, the transformation of the mode of production cannot be completed overnight, and now there is no such internal motivation, so man's demand for nature will not change much.

Even if the problem is right in front of you

But whether you want to govern and whether you have the ability to govern is still a question.

However, the adverse consequences have been shown. In the past decade, the number of sandstorms in the Gobi region in Mongolia has quadrupled compared with that in the 1960s. Maybe the extreme weather will become more and more frequent in the future, and the sandstorm in northern China is an early warning. No country can stay out of environmental problems.

The tourism department will make more efforts to promote dust-free.

Can't stop the dust all over the sky.

(figure: tourism.omnogovi.gov.mn) ▼

References:

Https://en.wikipedia.org/wiki/Mongolia

"the relationship between Mongolia's ecological environment and its desertification", Liu Shujuan, AriunaaOchir, Liu Hujun, Liu Kailin, Li Jingjing, Wan Xiang, Chen Fang

Mongolia Statistical Yearbook 1998

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