What are the causes of drought in southwest China? What measures should be taken to solve it?

drought is rampant and thirst is spreading. Faced with the continuous development of drought, under the great attention and strong leadership of the CPC Central Committee and the State Council, the relevant departments of the central government took urgent action, made careful arrangements, conducted scientific command, made accurate forecasting, carefully dispatched, issued emergency notices one after another, launched emergency plans one after another, and transported relief funds and materials to the disaster areas one after another. At present, drought relief work is progressing in an orderly and fruitful way. According to the statistics of the National Defense General Office, as of March 25th, the cultivated land in five provinces (autonomous regions and municipalities) of Yunnan, Guizhou, Guangxi, Sichuan and Chongqing was 96.54 million mu, accounting for 85% of the whole country, and the number of people suffering from drinking water due to drought reached 17.94 million, accounting for 79% of the whole country. Disaster is an alarm, and disaster is an order. The National Defense, located in Baiguang Road, Beijing, is always the "hub" for commanding flood control and drought relief throughout the country. In response to the increasingly severe drought situation, the National Defense General and the Ministry of Water Resources launched a Class II emergency response to drought in time. At present, 33 working groups have been sent to the disaster area. At the same time, this year's drinking water relief and irrigation area reconstruction project plan and construction funds for key counties of farmland and water conservancy were issued in advance, focusing on heavy drought areas to support drought relief and disaster reduction in dry areas. In the face of severe drought, the most practical, urgent and most concerned thing is to let the people have water to drink. On the 25th, the Ministry of Land and Resources held a coordination meeting on emergency response to drought in southern China in Kunming, and further deployed the groundwater drought-resistant drilling operation of the land and resources system in the southern arid area. It is planned to complete the construction of 2 deep wells and 1,1 shallow wells in Yunnan, Guizhou and Guangxi areas with severe drought within one month, directly solving the drinking water difficulties of about 2 million people who lack water. Accurate weather forecast is an important basis for timely organizing drought moisture assessment and grasping favorable opportunities to carry out artificial precipitation enhancement. Since the China Meteorological Bureau launched the Class III emergency response to major meteorological disasters on February 27th, it has sent five working groups to Yunnan, Guizhou, Guangxi, Chongqing and Sichuan provinces (autonomous regions and municipalities) to inspect and guide the meteorological services for drought relief and disaster reduction. At the same time, the Central Meteorological Observatory and the National Climate Center hold rolling discussions with the meteorological bureaus of Yunnan, Guizhou, Guangxi, Chongqing and Sichuan provinces (autonomous regions and municipalities) on short-term, medium-term and extended-term weather forecasts and drought development trends in dry areas every day, especially for major turning weather such as rainfall, and timely organize special discussions on weather and short-term climate. In order to ensure the price stability of basic necessities, the National Development and Reform Commission requires the competent price departments in Chongqing and Yunnan to strengthen the supervision and inspection of market prices and deal with price violations according to law. In response to some news rumors, the price department of the Development and Reform Commission issued a well-founded and informative clarification announcement through in-depth investigation and analysis, pointing out that "the drought in southwest China has little impact on the national rice price". In order to further enrich the grain stocks in drought-stricken areas and ensure the market supply and price stability in dry areas, the national grain department will transfer 1.42 million tons of grain to drought-stricken areas such as Yunnan, Guizhou, Guangxi, Chongqing, Sichuan and Gansu before the end of July. Further increase the assistance to the affected people and properly arrange the lives of the people in need in the disaster areas. Since the occurrence of the severe drought, the National Disaster Reduction Committee and the Ministry of Civil Affairs have launched five national emergency responses to disaster relief, including one secondary response, one tertiary response and three quaternary responses, and sent five working groups to the disaster area to help carry out drought relief work. The Ministry of Finance conscientiously does a good job in drought relief and disaster reduction, timely allocates disaster relief funds, and fully supports drought-stricken areas to carry out drought relief work such as solving drinking water difficulties for people and livestock, helping the people affected by the disaster, and restoring agricultural production. Since the beginning of this year, the Ministry of Finance and the Ministry of Civil Affairs have allocated 16 million yuan of central drought relief funds to help solve the basic living difficulties of the affected people such as rations and drinking water. In order to give full play to the support of science and technology for drought relief, the Ministry of Science and Technology launched the southwest drought disaster emergency mechanism on March 19, and urgently studied and formulated the "South Drought Relief Science and Technology Action Plan", and organized agricultural experts from China Academy of Agricultural Sciences, China Agricultural University and other units to rush to Yunnan to provide technical support in ensuring drinking water for people in disaster areas, popularizing agricultural drought relief technology, preventing disasters and diseases, and preventing geological disasters that may occur in the subsequent rainy season. Grasping drought resistance and disaster reduction on the one hand and spring ploughing on the other is related to the steady increase of grain production and the continuous increase of farmers' income this year. Based on the principle of "Koharu lost Da Chun to make up for it" and stabilizing agricultural production throughout the year, the Ministry of Agriculture issued six measures to further guide drought relief in southwest China, organized expert guidance groups such as wheat, rape, sugarcane and vegetables and experts in industrial technology systems, went deep into drought-stricken areas to carry out roving guidance, helped farmers to implement various scientific drought-resistant measures, and worked hard to water and protect seedlings in areas where water resources permit, focusing on field management, so as to ensure the protection of Taneda. At the same time, in view of the tight supply of hybrid corn and rice seeds in Yunnan, seed enterprises such as China Seed Group Co., Ltd. were organized to select corn seeds such as Great Wall 799 suitable for Yunnan planting and transfer them to Yunnan. First, the severity of the drought is shocking

From September 29 to March 21, most areas in Yunnan, Guizhou, Sichuan, Chongqing and Guangxi suffered from a once-in-a-century drought. The drought lasts for a long time, affects a large area and involves a large population.

The author lives in Anshun City, the hinterland of Guizhou Province. From September last year to March 26th this year, there was almost no rain in Anshun City for 24 days. According to the meteorological department's standard of "continuous rainless days, more than 61 days in spring, more than 46 days in summer and more than 91 days in autumn and winter", the drought in most areas of Guizhou, such as Anshun, is listed here.

the water area of many reservoirs is reduced to one-half to one-third. The author went to a river in the country with constant flowing water all the year round, and found that the long riverbed was like a paddy field, and the silt in the riverbed was cracked, and some cracks were as wide as 3 ~ 4 cm. Walking along the river bank for a long time, occasionally there is still water in a river ditch. Shallow ponds of 2 to 3 square meters have become the last water area for ducks raised by duck farmers to survive. Hundreds of ducks have less water and more ducks, and because the water doesn't flow, its color has already become thick ink, and it smells bad. If the drought continues, it will be difficult for ducks living in water to find even smelly ponds. Seeing such a scene makes people worry about the living conditions of these ducks, and then reminds them of how people who eat these ducks and duck eggs will feel and what impact they will have on their health.

In rural areas at this time in previous years, the leaves of rape in the fields were green and yellow, and the wheat seedlings were lush and full of spring everywhere. However, this year, due to the lack of water, the farmland in the high places is cracked and desolate, and there are sparse and thin rapeseed of 2 to 3 centimeters in the farmland in the low places. The desolate scene is like the severe winter season, which is distressing.

According to media reports on March 2th, 21, people in dry areas have difficulties in life, bathing has become a luxury, and some rural people pick wild vegetables to satisfy their hunger. While there is still no obvious rainfall in the heavy drought area in southwest China, the spring drought in North China will gradually emerge and develop.

Looking at the reality that drought has occurred one after another in China this year, it is getting worse every year. Although the author is not a meteorologist, his concern makes him think about the causes of drought.

Second, the analysis of the causes of drought by meteorologists has not touched the essence

Recently, I read some analysis of the causes of drought in Southwest China by meteorologists on the Internet and newspapers. However, most analysis of drought causes is limited to the description of the phenomenon itself; A few analyses involving reasons always make people feel as if they have not talked about the essence of the problem. Of course, the author also knows that the weather forecast itself is a thing that is difficult to be accurate so far, and perhaps it is because the experts in China are ashamed to express their opinions.

at this critical moment of drought, such as fire fighting, whether we can provide timely and accurate meteorological analysis to the public and relevant social departments is neither a simple meteorological academic issue, nor is it a leisure topic for meteorologists to talk about after a meal, but it is not only related to people's livelihood, but also to the overall situation of social stability.

The main points of the analysis of the disaster caused by meteorological experts from a country and a province, which are widely quoted by the media, are summarized.

one: firstly, the plateau thermal factors of the Qinghai-Tibet Plateau; secondly, the influence of El Nino phenomenon; thirdly, the timing of cold air is not well grasped.

Second, the label of "climate warming" should not be casually deducted. Drought is a continuous cumulative effect, and the continuous low precipitation and high temperature are the direct causes of drought. Less precipitation in summer and autumn leads to dry water from rivers and insufficient water storage in reservoirs and ponds. At the same time, the continuous high temperature in autumn and winter leads to the intensification of soil moisture evaporation, which promotes the development of drought.

I think it's a layman's reason. After reading the above two analyses, I don't know what to say. Now I analyze them as follows.

One saying is that the plateau thermal factor of the Qinghai-Tibet Plateau is that there was less snow on the Qinghai-Tibet Plateau last winter than normal, which further affected the surrounding drought. However, experts did not tell or put forward their own views on the reason why the general public wanted to know why the snowfall on the Qinghai-Tibet Plateau decreased last winter. Experts use the influence of El Nino phenomenon to explain the cause of drought in southwest China (especially in Sichuan) this year, and think that there is less water vapor entering southwest China from the south. If the occurrence of this drought coincides with the occurrence of El Niñ o this year, this conclusion seems to be one of the reasons. However, the author observed that the rain clouds passed through Anshun for more than 2 days, not less than 1 times, but it was difficult to form rainfall. This phenomenon is difficult to coincide with the expert's statement that a lot of water vapor bypassed the dry area. In particular, the author still vaguely remembers the tragic situation of the historic drought that occurred in Chongqing in 22 and 26; In addition, Yunnan Province, which is located on the tropical edge, has experienced frequent droughts in recent years, and forest fires have continued year after year. It is really hard to believe that this drought is essentially related to the El Niñ o phenomenon that has occurred regularly for many years. Therefore, the author believes that local meteorological problems should not only consider the influence of the big environment on local meteorology, but also consider the influence of the specific environment on local meteorology.

experts say that cold air does not grasp the opportunity to enter the inland, and then meets warm air in the inland to form rainfall. I can't imagine the lifeless and thoughtless cold air flow, so how to ask it to grasp the opportunity. If this argument is the imagination of experts on romantic occasions, it is understandable. But it happened that experts answered the scientific questions raised by reporters on behalf of the people on very serious occasions.

Secondly, the label of "climate warming" should not be casually deducted, and drought is a persistent cumulative effect, which I agree with very much. However, according to the expert's statement that the continuous low precipitation and high temperature are the direct causes of drought, the author thinks that the expert's conclusion is that the final cause of drought is not given. According to simple logic, as long as people in their right mind are eager to know what causes the problem that precipitation will continue to be low and temperature will continue to be high. Only by understanding this essential problem can it help the drought relief and disaster prevention in the future. Second, the direct reason given by experts did not reveal its relationship with human activities.

judging from the current human capacity, it is a natural phenomenon that the continuous low precipitation and high temperature are temporarily difficult for human beings to change-the occurrence and persistence of this drought is proof. Then, according to the conclusion given by experts, as long as there is a similar drought in the future, people will only have the fate of waiting, because it has nothing to do with human activities, and of course there is no need to change anything.

In addition, some people in the media think that the drought is caused by geological factors, which seems to be reasonable from the meteorological related factors. However, the author believes that although the geological influence exists, it is a gradual process, and the accumulation of earthquake energy is not completed in a year or so. Therefore, the drought caused by geological factors should be characterized by decreasing rainfall year by year, and there will never be little or no rainfall suddenly for such a long time.

As for some so-called experts who think that the drought is caused by the excessive construction of reservoirs and power stations, I think it is even more nonsense. Have you noticed that no amount of reservoirs occupy a limited area compared with the vast surface (the author estimates that the area occupied by reservoirs is less than a dozen to a few tenths of the area of mountains and land). The amount of water conservation on vast land should be several times that of reservoirs, and its ability to evaporate water vapor should be much more than that of reservoirs. Readers can change the land in the Yunnan-Guizhou arid area from the TV picture into a ravine with a crack width of several to 1 cm and a depth of 1 to 2 cm. You can know how much water the soil originally contained by evaporation. Not to mention the vast paddy fields and the ability of many plants and trees to contain water and evaporate water vapor.

in today's era, understanding meteorological problems is not only the needs of the general public for survival and production, but also the needs of governments at all levels and managers of relevant enterprises and institutions. Meteorologists can't say something without depth and guidance like a non-professional. Although the author also understands meteorological work and the difficulties of some experts, the purpose of taxpayers to support meteorological experts is to get timely and effective guidance from experts when meteorological problems occur. I think this is the unshirkable duty and obligation of meteorological experts, and this wish should not be excessive.

If experts can't make an accurate judgment on the cause of the drought, and then guide the public to take active measures, it won't be long before today's ducks in front will be our tomorrow.

Third, human factors should be the fundamental reason for the continuous droughts in various parts of China in recent years.

As a non-meteorological professional, although I dare not worry about the country and the people, I am concerned about the draught problem that everyone is concerned about. From the perspective of comprehensive disciplines and history, the author puts forward the causes of droughts in five provinces and cities in southwest China around 21. As well as the hypothesis of drought causes in many parts of China in recent years, the author believes that these droughts should be the inevitable result after the balance of natural environment in these areas is broken by human activities, and the abnormal performance after the cumulative effect of human activities on meteorology reaches a critical point.

the reasons and arguments are as follows.

1. The soil vegetation and water conservancy facilities are seriously damaged, and the water conservation capacity is reduced.

In agricultural production, in order to pursue high yield, many farmers use a lot of pesticides such as chemical fertilizers and herbicides, and use the land in a predatory way, which leads to soil hardening, serious desertification and reduced water-holding capacity. Under the same volume of water irrigation, the water-bearing period of farmland is obviously shortened. Burning wasteland and expanding farming will reduce the number of plants on the surface and weaken the ability of water conservation. The total amount of plants lost by deforestation exceeds the total amount of plants brought by artificial succession forests, and the effect of returning farmland to forests is not in place. The most important cause of drought is the weakening of water conservation ability caused by vegetation destruction.

under the land contract system, the construction of farmland water conservancy has generally come to a standstill, and for a long time, all localities have only used it without maintenance, which has abandoned a large number of original water conservancy facilities, and the original water storage areas have decreased year by year, losing the function of flood control and drought relief. In the rainy spring and summer season, a large amount of rainwater from the water falling from the sky quickly returns to the ocean through surface runoff. After the rainy season, quite a few places fell back into drought when there was no water conservancy construction.