Frost's Descent is the 18th of China's 24 solar terms, and the last of autumn. It signifies that the weather has become cold. When the water vapor close to the ground saturates, and the ground temperature is below zero, it condenses into tiny white ice needles with a loose structure on the grass.

Watch this video by Weather China, an online weather service of the China Meteorological Administration, to find out more.

(Cover image a screenshot)

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