Viewing Rime on Dadengzi Mountain

　　Rime, commonly known as "tree hanging," is a common sight in northern China and a natural phenomenon similar to frost that can be observed in the region during winter. It is a type of ice and snow scenery. It forms when countless fog droplets below zero degrees Celsius, but not yet frozen, accumulate and freeze onto objects such as tree branches as the wind blows, resulting in white, opaque, granular sediment deposits.

　　Therefore, the rime phenomenon is very common in northern China and also frequently seen in high-altitude areas of the south, as long as there are supercooled water droplets in the fog.

　　Historical Records

　　The Song Dynasty poet Zeng Gong wrote in his poem "Winter Night Affairs": “The fragrance fades, the felt rug warms the couch; the moon dims, a thousand doors shiver in rime’s cold touch. I’ve heard it said that from this sign, a rich harvest springs — I raise the lantern’s glow to gaze again at the rime’s soft hush.” His own note reads: “In Qi, the cold is severe; night vapors turn to fog, condensing on trees. Come morning, it looks like snow, and when the sun rises, it drifts across steps and courtyards — truly lovely. The people of Qi call it rime. There’s a saying: ‘Rime upon rime, the poor man’s store of rice.’ It’s seen as an omen of a bountiful year.”

　　The Song people called it "rime" and believed it to be "an omen of a bountiful year." This belief likely stems from the ancient name for rime: "tree fruit."

　　Formation Principle

　　Rime forms when supercooled water droplets (with temperatures below zero) collide with objects that are also below freezing. When the droplets are so small that they freeze instantly upon contact, they create a layer or deposit of rime.

　　A rime layer consists of tiny ice particles with air pockets between them, resulting in the typical white appearance and granular structure. Because the supercooled water droplets freeze rapidly, the cohesion between adjacent ice particles is weak, making them prone to falling off the surface they cling to. Rime is most likely to form on mountaintops surrounded by supercooled clouds, and it is also a common form of ice on eaves. In cold weather, the steam near springs, rivers, lakes, or ponds can also produce rime.

　　Rime is a widely appreciated natural beauty, but it can sometimes become a natural disaster. Severe rime can weigh down power lines and trees, causing damage.

　　Address: Raohe County, Shuangyashan City, Heilongjiang Province