How cold was the winter in ancient China?

In the long ancient times, from 3000 BC to the present 5000 years, the climate in China has also experienced great fluctuations, resulting in a cold climate indirectly. According to the famous meteorologist Zhu Kezhen's paper "Preliminary Study on Climate Change in China in the Last Five Thousand Years", there were four relatively long cold periods in China history. The first cold period was in the early years of the Western Zhou Dynasty and lasted for a century or two. The second cold climate period occurred from the early years of the Eastern Han Dynasty to the second half of the 3rd century. It was a process of gradual cooling, then in the 7th century, and then began to warm up. Hundreds of years from cooling to warming were the period of confrontation between the Five Revolutions and the Southern and Northern Dynasties, and it was the most chaotic time in China. The third cold weather period occurred at the beginning of12nd century, and the climate in China became colder and colder. 1 1 1 recorded for the first time that the 2250 square kilometers Taihu Lake between Jiangsu and Zhejiang was not only frozen, but also opened to traffic. All oranges in Dongting Mountain of Taihu Lake froze to death, and the snowfall in Hangzhou, the capital of the Southern Song Dynasty, continued until late spring. This cold weather lasted for more than 200 years. The fourth cold climate period was17th century, which was the stormy last days of the Ming Dynasty.

The first thing is to put on more clothes and keep warm. Cotton is an exotic crop, which was not popular in China until the Ming Dynasty. Before that, most people would not wear cotton-padded clothes. Kudzu, hemp and silk are all local textile raw materials in China. Rich people naturally use silk. When the weather is cold, they will put silk brocade in their clothes to keep warm, and they will also wear furs made of sheepskin, fox skin, mink and other animal skins. As for the fabrics woven by the poor with flax or other plant fibers, the effect of keeping out the cold is naturally unsatisfactory. Fortunately, by the Ming Dynasty, people could generally put on cotton-padded clothes.

The Tang and Song Dynasties were in the middle-thick interglacial period, and there was a process of warming up for hundreds of years. Later, in the Yuan and Ming Dynasties, after the temperature dropped, the so-called greenhouse effect appeared again. But from a professional point of view, the ability of carbon dioxide does not seem so great, and it has always been controversial that carbon dioxide changes the temperature. Although the current mainstream is that carbon dioxide causes the greenhouse effect, many people think that the beginning of the industrial revolution happened to meet the temperature rise at the end of the interglacial period.

The average winter temperature in Beijing in the Ming Dynasty may be about 2℃ lower than it is now. The lowest temperature in the southeast coast in winter in the early Qing Dynasty may be 5℃~7℃ lower than it is now. In the sixth year of Hongzhi (1493), heavy snow fell in the Huaihe River Basin until February of the following year, that is to say, it snowed for half a year. In the eleventh year of Xianfeng (186 1), heavy snow fell in Puyin, Hubei Province, and the ground was five or six feet deep, killing many people and animals. Wang Yue, a poet in A Qing, once wrote a poem describing the frozen scene of Qiantang River in the 18th year of Guangxu (1893)-"The atmosphere is not warm, and there is a suspected flood. I have heard of the tidal bore in Qiantang, which is as flat as a rock. I also smell the seaside and look at the ice. It is very old, but I was born here. " An old saying tells the degree of cold in those days.

The ancients found that the soil around the stove would change in nature under the action of fire, which not only hardened, but also kept for a long time, so they invented the heating method of "baking ground", which is also commonly known as "baking hot ground" It is to heat a clean flat land with fire and use the thermal inertia of the soil to keep warm, and the warmer can lie on it to keep out the cold. This heating method is also recorded in Zuo Zhuan. In the tenth year of Lu, Song Guojun died, and his son Song had a wake, so he needed to "sleep on the grass" and could not wear clothes to keep out the cold. It didn't kill his son. At this time, in order to please the monarch, an attendant named Wang roasted the sitting place with fire in advance, and Song, who was comfortably awake, was very happy. He hated Yu Sun, was flattered, immediately gloated, and was promoted ~