SafekipediaA snowflake is a single ice crystal that is large enough to fall through the Earth's atmosphere as snow. Snow looks white even though it is made from clear ice. This happens because the many small crystal facets of snowflakes scatter the sunlight between them, making it appear white to our eyes.
Each snowflake starts its journey around a tiny particle known as its nucleus. As it grows, water droplets freeze onto it and slowly form a crystal. The shape of a snowflake changes as it moves through different temperatures and humidity levels in the sky. Sometimes, snowflakes even join together with others, creating unique patterns.
Because of these changing conditions, no two snowflakes are exactly alike. They come in many different shapes and sizes. Scientists have found that snowflakes can be grouped into eight broad classifications with at least 80 different types. The basic shapes include needle, column, plate, and rime, which can combine in many interesting ways.
Formation
See also: Snow science
Snowflakes start to form around tiny particles in cold, moist air. These particles can be dust, clay, or even tiny bits of living things. Once a snowflake begins to form, it grows by collecting water vapor from the air. This process happens when the air is very cold and has more moisture than it can normally hold.
As snowflakes grow, they often form beautiful, branching shapes. Most snowflakes look white because their many tiny parts scatter all the colors of light. Even though snowflakes are often shown as perfect stars, each one is unique due to the many water molecules that make it up. The shape of a snowflake depends on the temperature and humidity where it forms, which is why no two are exactly alike.
Classification
See also: Classifications of snow § Snow crystal classification
Snowflakes come in many beautiful and detailed shapes. Scientists have found that each snowflake is usually unique, though some very similar ones can be made in labs. The shape of a snowflake depends mostly on the temperature and moisture where it forms.
In warmer freezing air, snowflakes are thin and flat. In colder air, they can look like hollow columns or needles. Even colder, and they become flat again, often with branches. Experts have identified around 80 different shapes for snowflakes, grouped into categories like needles, columns, plates, and more complex forms.
| Temperature range | Saturation range (g/m3) | Types of snow crystal below saturation | Types of snow crystal above saturation |
|---|---|---|---|
| 0 °C (32 °F) to −3.5 °C (26 °F) | 0.0 to 0.5 | Solid plates | Thin plates Dendrites |
| −3.5 °C (26 °F) to −10 °C (14 °F) | 0.5 to 1.2 | Solid prisms Hollow prisms | Hollow prisms Needles |
| −10 °C (14 °F) to −22 °C (−8 °F) | 1.2 to 1.2 | Thin plates Solid plates | Sectored plates Dendrites |
| −22 °C (−8 °F) to −40 °C (−40 °F) | 0.0 to 0.4 | Thin plates Solid plates | Columns Prisms |
Use as a symbol
The snowflake is a popular symbol, especially during the Christmas season. In many places, snowflakes stand for purity and are linked to the idea of a "White Christmas." People often make paper snowflakes by folding paper, cutting a design, and then unfolding it to reveal the pattern.
Snowflakes also represent winter and cold weather. For example, some winter tires have a snowflake symbol to show they work well in snow. The snowflake has been used in the emblems of several Winter Olympics games. In Canada, a special snowflake design represents the country’s northern roots and rich culture.
Images
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