In the era without computers, how do meteorologists predict the weather?

In China's earliest poetry collection, The Book of Songs, the ancient people's experience of looking up at the sky was recorded. The north wind in the Book of Songs: "The north wind is cool, and the rain and snow are wet. ..... The north wind roared, and it was raining and snowing. ..... "It means that the cold north wind is blowing, and the wind is strong, bringing heavy rain and snow. Isn't this the earliest description of cold air in history?

Experience is the main basis for the ancients to make weather forecasts. As early as the Han dynasty, there have been examples of forecasting sunny and rainy days by using the principle of string sensing humidity. In the book Tian Wu Jia Xing, Lou Yuanli in the late Yuan Dynasty and early Ming Dynasty also said: If the clean strings with good quality suddenly become loose and wide, it is because the piano bed is wet; This phenomenon indicates that it will rain. He also said that if the tone of the harp strings is not well tuned, it also indicates rainy weather, which is also scientifically based.

People's understanding of weather phenomena is deepening. Meanwhile, Shen Kuo, a scientist in the Song Dynasty, recorded a tornado in a county in A.D. 1076, which is the earliest tornado record in East Asia. He explained the reasons for the formation of rainbows and recorded "ball lightning". Meng Qian Bi Tan also recorded a successful rainfall forecast case in Shen Kuo.

Zheng He's voyage to the West in the Ming Dynasty reflected the deepening of the ancients' understanding of the weather. He began to take the initiative to use wind energy during his voyage. At that time, it was very remarkable to sail on wooden boats and only rely on natural wind to overcome various difficulties at sea. According to records, Zheng He's fleet encountered headwinds and crosswinds. As long as the sail surface was tilted to a certain angle and the wind blew on the sail surface to form a force perpendicular to the sail surface, it could push the ship forward.

Dating back to more than 300 years ago, there appeared a continuous meteorological record and a department specialized in meteorological work-"Qin" in China.