Snödriva

Snödriva, or snowdrift, is a mound or ridge of snow formed by wind-driven transport and deposition of loose snow. It commonly develops where wind encounters an obstruction or along the leeward side of features such as hedges, fences, roads, or buildings, causing snow to be lifted, carried, and deposited there. Snow is carried by the wind and settles when wind speed decreases or turbulence increases.

Drifts typically have a rounded windward slope and a steeper leeward side and can range from decimeters to several meters in height, depending on wind speed, duration, snow properties, and fetch. Formation is influenced by surface roughness, terrain, and the historical wind regime. Snödriva is common in cold climates with light, dry, or moderately moist snow and frequent gusty winds. In Sweden, drifts often accumulate along roadsides, fields, and in open areas near buildings or fences, and they may shift with the weather.

Impacts include blockages of roads, driveways, or entrances, reduced visibility, and changes to drainage and snow distribution around structures. Removal is performed by snowplows, snow blowers, or manual shoveling; measures such as windbreaks or snow fences can reduce drift formation and improve safety and accessibility during winter.

Etymology: snödriva derives from Swedish snö (snow) and driva (to drive or drift).