Snowdense

Snowdense is a term used in snow science to refer to the density of snow, defined as the mass per unit volume of snow and typically expressed in kilograms per cubic meter (kg/m^3). It reflects how compact or airy a snowpack is and varies with moisture content, metamorphism, temperature, and time since precipitation.

Value ranges for snowdense vary with snow type. Fresh fallen dry snow tends to have low density, roughly 5 to 30 kg/m^3 depending on crystal size and humidity. As snow settles, compacts, or is wind-packed, density can rise to about 50 to 150 kg/m^3. Wet or heavy snow commonly ranges from 200 to 400 kg/m^3, while very dense wet snow and crusts can exceed 400 kg/m^3 and, in extreme cases, approach 700 kg/m^3. Over a season, snowpack densities generally fall between about 50 and 500 kg/m^3, with local conditions producing higher values.

Measurement of snowdense is typically done by collecting a known volume of snow and weighing it, or by extracting snow cores from the pack. The relation to water content is often expressed via the snow-water equivalent (SWE), where SWE equals snow depth times the ratio of snow density to water density. Field instruments such as density cutters, snow densometers, or infrared sensors provide estimates of density in situ.

Snowdense influences several aspects of snow behavior and its consequences. It affects avalanche risk and snow stability, governs meltwater runoff and groundwater recharge, and determines the structural load that snow imposes on roofs, roads, and other infrastructure. It is also a key parameter in hydrological and climate models, helping to translate snow depth into potential water resources and to understand seasonal evolution of the snowpack.