How to make pictures to predict the weather?

This experiment is a small experiment to make a map that can predict the weather by chemical method.

Experimental materials and appliances: cobalt chloride (available in chemical stores), salt, blotting paper.

Experimental steps:

1. Dissolve two tablespoons of cobalt chloride and one tablespoon of salt in water.

2. Dip the new white blotting paper into the solution. Blotting paper will turn pink when it is wet, and blue when it is dried in the sun or dried.

3. Draw a color picture, a seaside or a landscape, and stick the processed blotting paper on the sky.

When the weather is clear, the sky on the picture is blue; When the weather is wet, the sky turns pink, which indicates that the weather will change. The principle of this small experiment is that salt is easy to get wet, and the color of dried cobalt chloride changes from blue to pink after getting wet. Paintings made with chlorinated drilling fluid are very sensitive to the humidity change in the air, and the humidity degree of the air can be known from the color change on the picture. The air humidity is high, and the possibility of weather change is high.