Rimed snow

Rimed hexagonal snow crystal

Rimed snow is a type of snow that occurs when snowflakes encounter supercooled water droplets in the atmosphere. These droplets freeze upon contact with the snowflakes, forming a layer of ice. This process is known as riming, and it results in snowflakes that are heavier and more granular than typical snowflakes.

Formation

Rimed snow forms in clouds where the temperature is below freezing, and there is an abundance of supercooled water droplets. As snowflakes fall through these clouds, the supercooled droplets collide with the snowflakes and freeze instantly. This process can continue as the snowflakes fall, leading to the accumulation of multiple layers of ice.

Characteristics

Rimed snow is typically denser and more compact than regular snow. The presence of ice layers makes the snowflakes less delicate and more resistant to melting. This type of snow is often associated with graupel, which is a form of heavily rimed snow that appears as small, soft pellets.

Impact on Weather and Climate

Rimed snow can influence weather patterns and climate in several ways. Its increased density can affect the albedo of the snowpack, leading to changes in how much sunlight is reflected or absorbed. Additionally, rimed snow can impact the stability of snowpacks, potentially increasing the risk of avalanches.

Related Phenomena

Rimed snow is closely related to other forms of precipitation and atmospheric phenomena, such as freezing rain, sleet, and hail. Each of these forms involves the interaction of supercooled water droplets with other particles in the atmosphere.

See Also

• Snow
• Graupel
• Supercooled water
• Albedo
• Avalanche
• Freezing rain
• Sleet
• Hail