What does it mean when the solar term comes to goose feather and heavy snow?

It's time for heavy snow. Goose feather heavy snow refers to snowflake polymer.

The so-called "goose feather snow" is actually a polymer of snowflakes. As we all know, snowflakes are small hexagonal ice flowers condensed by water vapor in the air, with loose branches. When it snows heavily, the density of snowflakes falling from the air is relatively high, so many snowflakes cling to each other and blend together before landing. These snowflakes stick together and even fuse many times, which is called "goose feather snow".

There are many shapes of snowflakes, and each snowflake is an extremely beautiful pattern, which even many artists admire. Snowflakes are mostly hexagonal, because snowflakes belong to hexagonal system. There are two main shapes of small ice crystals in the "embryo" of snowflakes in the cloud. One is hexagonal, slender and called columnar crystal, but sometimes its two ends are pointed and look like needles, called acicular crystal. The other is a hexagonal flake, just like a flake cut from a hexagonal pencil, called a flake crystal.

Formation of snowflakes

Snowflakes grow from small ice crystals, and most ice molecules are hexagonal, so most snowflakes are hexagonal, and the shape of each snowflake is not exactly the same. The diversity of snowflake shapes is closely related to the water vapor conditions when it is formed.

As the ice crystals grow, the water vapor near the ice crystals will be consumed. Therefore, the closer to the ice crystal, the thinner the water vapor and the lower the supersaturation. Close to the surface of the ice crystal, because the excess water vapor has condensed on the ice crystal and just reached saturation. In this way, the density of water vapor near the ice crystals is smaller than that far away from the ice crystals.

Water vapor moves from around the ice crystals to where the ice crystals are. Water vapor molecules first meet the corners and protrusions of ice crystals, where they condense and make ice crystals grow. Therefore, the corners and protruding parts of ice crystals will grow rapidly first and gradually branch.