How does summer predict the weather?

Before and after sunrise and before and after sunset, a large part of the sky, especially the sky near the sun, is stained with color. When there are clouds in this part of the sky, the clouds are also colored. From the horizon to the sky, the order of colors is red, orange, yellow, green, cyan, blue and purple. Sometimes individual colors may not be obvious, but the order remains the same. This is the sunset glow. It is called morning glow before sunrise and sunset.

The sunset glow indicates a sunny day.

How is Xiaxia formed? In fact, it is the same as the reason why the sky produces blue. It is caused by the scattering of air molecules. Just before and after sunrise and sunset, sunlight passes through the thick atmosphere and is scattered by a large number of air molecules. According to calculation, the thickness of the atmosphere penetrated by the sun at the horizon is 35 times that of the atmosphere penetrated by the sun at the head during the day. Because sunlight is scattered by a large number of air molecules, purple and blue light is weakened the most, and there is little left when it reaches the horizon, leaving only yellow, orange and red light with longer wavelengths. After these rays are scattered by air molecules above the horizon and impurities such as dust and water vapor, the sky there looks beautiful. The more impurities such as dust and water vapor in the air, the more obvious this color is. If there are clouds, they will be dyed bright orange and red.

In addition, the water vapor and dust in the atmosphere are the basic factors that affect the appearance of Xia Xia. The more water vapor in the atmosphere, the redder the color of Xia Xia. The increase of air humidity usually occurs before the cyclone in bad weather approaches, so when bright red or orange light appears, it may indicate that the weather will get worse, and of course it may also indicate the occurrence of precipitation. As the saying goes, "Don't go out in the morning, travel thousands of miles at night", that is to say, the morning glow means rainy day, and the sunset glow means sunny day.