Indeed, there are large areas of Gobi and desert in the northwest of China, and many areas belong to arid or semi-arid climates, but this hot and dry scene is not from ancient times.
Dating back to the Han Dynasty, there was an ancient state on the northwest bank of present-day Lop Nur in Xinjiang and in the north of Ruoqiang County in Bayingolin Mongol Autonomous Prefecture, which we called "Loulan Ancient Country". As an ancient western country, its image in the historical materials is not hot and dry, but an oasis full of water and grass and livestock, which can fully deserve the reputation of "Saiwai Jiangnan", unfortunately, this Loulan oasis has long disappeared in the long river of history. The disappearance of the Loulan oasis is closely related to the diversion of the Peacock River and the shrinking of Lop Nur because of the deterioration of the environment, the Loulan people began to migrate south and conquered all the way to become the seven strongest in the western region, and finally in 448 AD, they were destroyed by the Northern Wei.
The ancient country of Loulan has disappeared, and the former Loulan Oasis has long disappeared, so is it possible for the Loulan Oasis to reappear in the future?
Now it seems that there are still some signs, because in recent years, there is a trend of changing from a dry and hot climate to a humid and hot climate in the northwest region of China. According to the data, in the past 50 years, China's overall precipitation has not changed significantly, but the precipitation in the northwest region has continued to increase, especially in the past 20 years, the summer precipitation in the northwest region has increased significantly, and the increase in precipitation has directly led to changes in the climate environment in some regions in the northwest. In the northwest of Gansu Province and the western part of the Hexi Corridor in China, there was once an inland river called the Shule River, which was called "Dark Water" in ancient times.
The Shule River is 540 kilometers long, with a basin area of 20,197 square kilometers, and there was once a terminal lake called "Haraki" at the tail of the Shule River.
According to historical records, the former Haraki water and grass are abundant and the lake is rippling, but later due to the deterioration of the ecological environment caused by various reasons, the Shule River has stopped flowing, and the Halaqi located at the end of the Shule River has dried up, all of which happened 300 years ago. However, in recent years, with the restoration of the Shule River channel, ecological water has been continuously replenished, and Harachi, which has dried up for 300 years, has once again shown a scene of turquoise waves, and according to the existing situation, Haraki's sleep has been relatively stable. The resurrection of Harachi is the result of a combination of two reasons, on the one hand, because the northwest region has increased precipitation year by year, and on the other hand, because of the rational use and planning of water resources in the northwest region.
In 2011, the "Comprehensive Plan for the Rational Utilization of Water Resources and Ecological Protection in Dunhuang" was implemented, and the Shule River Channel Restoration Project was completed, which became an important node in the resurrection of Haraki.
Coincidentally, the Heihe River, known as China's second largest inland river, also has a terminal lake called "Dongju Yanhai", due to the dry climate, Dongju Yanhai dried up twice in the 1960s and 1990s, but now Dongju Yanhai is not only abundant in water, but also has achieved 17 consecutive years of non-drying, and the water area has reached nearly 40 square kilometers. All of these changes are related to increased precipitation in the Northwest. So it seems that Loulan Oasis really has hope to reappear? It's hard to say yet.
Although the precipitation in the northwest region shows an increasing trend, and the precipitation in some areas has increased significantly, on the whole, there has been no qualitative change.
Although the precipitation in the northwest region has continued to increase in the past 50 years, it has not yet reached the level of the beginning of the last century, and it is difficult to say whether it will eventually change from quantitative change to qualitative change, because this requires a comprehensive consideration of the climate change trend in all aspects, and it is difficult to make an accurate estimate. Compared with being able to recreate the Loulan Oasis, another question that actually needs us to worry about is whether the increase in precipitation in the northwest is a good thing or a bad thing. Precipitation is of course a good thing, how can it be a bad thing? This is not necessarily true, the key is how the increased precipitation comes from. If the increase in precipitation is due to the improvement of the environment, it is naturally good, but it does not seem to be so now.
In recent years, due to the increase in temperature, the glaciers in the northwest region have begun to melt, and the meltwater of glaciers has increased significantly compared with the past, so the increase in precipitation in the northwest region is closely related to the melting of glaciers.
What are the problems posed by glacier melting? This is very complex, and the melting of glaciers can lead to the emergence of various extreme weather, increasing the probability of natural disasters, and also bringing long-term ecological problems that are difficult to foresee. But glacier melting stems from rising temperatures, which are global problems beyond our control. Therefore, on the one hand, we must be vigilant about the problem of glacier melting and the temperature rise behind it, on the other hand, we must also make good use of the positive impact of glacier melting to promote the development of the climate and ecological environment in the western region in a good direction, after all, the increase in precipitation is still of positive significance for short-term environmental improvement.