During Ming and Qing dynasties, China's average temperature dropped to its lowest point in nearly 10,000 years, and academics called it "Little Ice Age." From end of Qing Dynasty to present, average temperature in China is still at lowest level in history and has not reached high temperature of pre-Qin, Qin-Han, Sui and Tang dynasties. So what impact did Little Ice Age of Ming and Qing dynasties have on China? Was Little Ice Age main cause of death of Ming Dynasty?

1. A brief history of climate change in ancient China.

According to research, average temperature in ancient China fluctuated several times. During pre-Qin period, temperature was high and rainfall was abundant, northernmost subtropical zone moved to Yanshan Mountains, and wild animals such as elephants and rhinos appeared in Yellow River basin. Since late Shang Dynasty, China experienced its first period of low temperatures, from about 1100 B.C. to 950 BC According to Bamboo Book Chronicle, during reign of King Xiao of Zhou, Han River froze twice.

In spring-autumn period, climate began to warm up again. From Spring and Autumn period to Western Han Dynasty, China experienced a warm period for about 800 years. At that time, plum trees, bamboo, etc. could grow in Yellow River basin, and in some areas there were two crops per year. . From Eastern Han Dynasty to Southern and Northern Dynasties, China experienced a cold period of about 600 years. During this time, Luoyang experienced heavy snowfalls in late spring, and Huai River was still frozen during Three Kingdoms period.

From Sui Dynasty to Northern Song Dynasty, China was in warm period of Middle Ages. At that time, agricultural belt moved north to Liaodong and Dunhuang. Since 880, temperature began to gradually fall. During Southern Song Dynasty, China again entered a cold period. For example, Taihu Lake froze over, and lychees in Fujian Province froze to death. Since then, average temperature in China has been falling.

Economic map of Tang Dynasty: northern border of rice cultivation crossed Yellow River basin

This downward trend in temperature continued until Ming and Qing dynasties, as well as until advent of "Little Ice Age". During Ming and Qing dynasties, both Yangtze River and Dongting Lake froze over. During Shunzhi period, Guizhou experienced heavy snowfall for 40 consecutive days. Until late Qing Dynasty, rivers in Sichuan were still frozen.

According to research, cooling has a certain connection with change of dynasty and ethnic migration. For example, during cold period of Western Zhou Dynasty, this was period when Rong and Di moved south, and finally Quan Rong destroyed Western Zhou Dynasty. During Eastern Han Dynasty and Southern and Northern Dynasties, northern nomadic peoples moved south on a large scale, and phenomenon of "five random China" emerged. Since Southern Song Dynasty, northern peoples continued to prosper, and three main dynasties Jin, Yuan, and Qing emerged.

During warm period, agricultural land was expanded, food crops increased, grain harvest increased, and economic power of Central Plains Dynasty was strengthened, which laid material basis for prosperity of Central Plains Dynasty. For example, powerful Western Han and Tang dynasties in Chinese history were in a warm period, while Eastern Jin and Southern Song were in a cold period.

Secondly, Little Ice Age of Ming and Qing dynasties contributes to era of great unification.

Ancient China was a typical agricultural society, and agriculture mainly included crop production and animal husbandry. The Little Ice Age of Ming and Qing dynasties mainly affected China from these two sides.

In terms of animal husbandry, due to cooling of climate, living space of ethnic groups of Mongolian Highlands and Northeast China became worse, a large number of livestock froze," report says. Due to cold climate, pasture economy has greatly declined, and a large number ethnic groups had to move south.Since Southern Song Dynasty in China, there has been a general trend of ethnic groups migrating south.

The Great Wall of Ming Dynasty: a barrier to migration of nomads to south

For example, nomads of Mongolian Highlands originally lived in Mobei, but entered Monan in large numbers during Southern Song Dynasty. During Ming Dynasty, agricultural management in Hetao Plain was quite difficult, and a large number of Mongols poured in here. Finally, Ming dynasty left Hetao Plain during Yongle period. The Duoyan Sanwei Mongols in area of ​​the Siliao River originally lived in Daxinganling area, but after Yongle, a large number of them moved south, north of Great Wall.

In northeast, Jurchens migrated from Heilongjiang River basin to Liaohe River. For example, Jianzhou Jurchens originally lived in Wugochen region in Songhua Basin, but began to move south during Yuan Dynasty, and settled in Liaodong region during Ming Dynasty.

Jurchen Migration Map of Jianzhou

The southward migration of northern minorities put enormous pressure on farming dynasty in Central Plains, and at same time hastened decline of farming dynasty. After Southern Song Dynasty, three powerful ethnic minority dynasties arose in China: Jin, Yuan, and Qing, which had something to do with colder climate and migration of ethnic groups to south.

At same time, colder climate also hastened decline of nomadic peoples. The colder climate not only reduced pastures and worsened pastoralism, but also accelerated drying up of lakes and rivers in northwest, making smooth flow of Silk Road more difficult. During Ming and Qing dynasties, importance of overland Silk Road greatly declined, and many ancient cities along Silk Road were flooded by a sea of ​​sand.

Under such circumstances, it became more difficult for Central Plains Dynasty to farm in western regions and Mongolia, and it also naturally made it difficult for Central Plains Dynasty to manage Mongolia and western regions. At same time, ethnic regimes in western regions and Mongolia also found it more difficult to govern their own ethnic groups. Due to decline of animal husbandry and reduced trade along Silk Road, economic power of nomadic regime is far inferior to that of Qin and Han, Sui and Tang dynasties, as well as Song and Yuan dynasties.

To dry northwest

In Qinghai-Tibet Plateau, colder climate has turned much of farmland into pasture, and population carrying capacity of Qinghai-Tibet is also much lower than that of Sui and Tang dynasties. Under Tang Dynasty, Qinghai-Tibetan Plateau could have had a strong Tubo dynasty, but under Ming and Qing dynasties, even if Qinghai-Tibetan Plateau was unified, it would be difficult to form a powerful dynasty because economy had already experienced a severe downturn.

Therefore, cold weather of Ming and Qing dynasties had a huge impact on all major ethnic groups in China, especially nomads. The cold climate oppressed northern ethnic groups to move south, forming a large trend of ethnic internal migration. However, due to cold climate, ethnic regimes of Mongolian Highlands, Western Regions, and Qinghai-Tibet overcame economic decline and eventually lost their ability to compete with Central Plains Dynasty, which became an important condition for great unification of China.

From this perspective, both Ming Dynasty and Qing Dynasty have ability to unite East Asian continent, and Ming Dynasty abandoned these cold places and decided to build Great Wall to protect itself, while Qing Dynasty uses this opportunity A unique opportunity has finally united East Asian continent and laid foundation for China's territory.

Thirdly, Little Ice Age accelerated shift of economic center of gravity to south.

After Anshi uprising, China's economic center shifted to south. In past, we have associated shift of economic center of gravity to south with war in north and migration of population to south. In fact, cooling of climate is also an important factor in shift of economic center of gravity to south.

Agricultural production in Yellow River basin has declined due to a colder climate. Many areas suitable for agriculture in past have turned into pastures and even deserts. Areas that could have two crops a year could degenerate to one crop a year during Ming and Qing dynasties.

As climate cools, precipitation decreases and many areas gradually transition from wet to semi-humid, semi-arid, or even arid. During Ming and Qing dynasties, number of droughts in northern region was much greater than floods. For example, at end of Ming dynasty, there was a 14-year continuous drought in Yellow River basin, which was directly related to peasant uprising at end of Ming dynasty.

However, to a certain extent, cooling has a positive effect on land development in Yangtze River basin. The colder climate hastened decline of tropical areas in south, and many areas where miasma had not yet developed became cropland. The undeveloped Yunnan-Guizhou Plateau, Pearl River Basin, and mountainous regions of Fujian were fully developed during Tang and Song dynasties, bringing country's arable land to a new peak.

As a result, economy of Ming and Qing dynasties moved further south. During Song and Song dynasties, it was "cooked in Suhu, world is full", and during Ming and Qing dynasties, it was "cooked in Huguang, world is full." At end of Ming Dynasty, "thousands of miles of red earth" situation arose in north and refugees were displaced, but weather in south was still smooth and songs and dances were peaceful, showing huge gap between north and south.

War in north and peace in south

Of course, we cannot exaggerate influence of Great Ice Age on Ming and Qing dynasties. The Ming and Qing dynasties were at stage of Little Ice Age, but grain yield of Qing dynasty was higher than that of Ming dynasty, and its population was much larger than that of Ming dynasty. The impact of Little Ice Age on agriculture was limited. Although Little Ice AgeIt may hasten demise of a dynasty, it is not root cause.