Zhuge Liang borrowed an arrow from the grass boat. Why can he conclude that there will be heavy fog that night?

? Zhuge Liang has a deep study of meteorology. We can know the weather changes in the next few days by observing the reactions of astronomical phenomena and creatures. After long-term observation of night sky phenomena, the ancients found that the direction of constellation movement is regular, which can be consistent with the climate change on the earth.

There is such a record in the ancient book Guanzi 4,000 years ago in China: "The barrel handle refers to the east, the world is spring, the world is summer, the barrel handle refers to the west, the next is autumn, the barrel handle refers to the north, and the world is winter." This is to judge the season by observing the position of the Big Dipper at dusk. And this method of observing the regular changes of the sky to determine the four seasons is called "observation time"

Now many old people also look at the future by observing things around them, such as: "white fog, gray fog." It was yellow and fat at night, and it rained heavily in the Ming Dynasty. Fog and rain in spring, fog and heat in summer, fog and cool wind in autumn and fog and snow in winter. The east wind sends moisture, and the west wind is dry; The south wind warms the air, while the north wind is very cold. It thundered in the southeast, but it didn't rain Dark clouds cover the fire and rain comes quickly. ?

Zhuge Liang in history is really an all-rounder When he grows up, he knows astronomy above and geography below. He is an outstanding politician, strategist, essayist, calligrapher and inventor. So he carefully studied the terrain and wind direction at that time, and according to these, he concluded that that day was the best opportunity these days, and he seized this good opportunity, so in the end he could achieve this effect.