snow patch on:
[Wikipedia]
[Google]
[Amazon]
A snow patch, is a geomorphological pattern of 
There is high soil moisture around the snow patch that supports growing of specific vegetation. Snow patch vegetation is very distinctive. It is usually dominated by species that tolerate a shortened growing season and is predominantly herbaceous. With increasing duration of snow persistence, non – vascular plants predominated over vascular plants for example Salicetum herbaceae, Salix herbacea etc.Wahren, C.-H.; Williams, R.J.; Papst, W.A. (2001): Alpine and subalpine snow patch vegetation on the Bogong High Plains, SE Australia, Journal of vegetation science, vol.12
At times water can be seen flowing downslope from the margin of snowpatches. The origin of this water may be from the melting of the snowpatch itself, from groundwater reaching the surface in slopes next to the snowpatch or from groundwater being forced to surface by obstructing
snow
Snow consists of individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes.
It consists of frozen crystalline water througho ...
and firn
__NOTOC__
Firn (; from Swiss German "last year's", cognate with ''before'') is partially compacted névé, a type of snow that has been left over from past seasons and has been recrystallized into a substance denser than névé. It is ice that ...
accumulation which lies on the surface for a longer time than other seasonal snow cover. Snow patches are known by a wide range of synonymous terms including snowpatches, snow beds, snow banks, and ice patches. Snowpatches are categorised by their longevity. Seasonal snowpatches melt prior to the return of the following winter's snowpack, semi-perennial snowpatches last occasionally to the following snowpack, while perennial snowpatches habitually last until the next winter's snowpack.
Snow patches often start in sheltered places where both thermal and orographical conditions are favourable for the conservation of snow such as small existing depressions, gullies or other concave patterns. The main process that creates these accumulations is called nivation
Nivation is the set of geomorphic processes associated with snow patches. The primary processes are mass wasting and the freeze-and-thaw cycle, in which fallen snow gets compacted into firn or névé. The importance of the processes covered by the ...
. It is a complex of processes that includes freeze–thaw action (weathering
Weathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs '' in situ'' (on-site, with little or no move ...
by the alternate freezing and melting of ice), mass movement (the downhill movement of substances under gravity), and erosion by meltwater
Meltwater (or melt water) is water released by the melting of snow or ice, including glaciers, glacial ice, tabular icebergs and ice shelf, ice shelves over oceans. Meltwater is often found during early spring (season), spring when snow packs a ...
which is the main agent of the surroundings' influence.
There is high soil moisture around the snow patch that supports growing of specific vegetation. Snow patch vegetation is very distinctive. It is usually dominated by species that tolerate a shortened growing season and is predominantly herbaceous. With increasing duration of snow persistence, non – vascular plants predominated over vascular plants for example Salicetum herbaceae, Salix herbacea etc.Wahren, C.-H.; Williams, R.J.; Papst, W.A. (2001): Alpine and subalpine snow patch vegetation on the Bogong High Plains, SE Australia, Journal of vegetation science, vol.12
At times water can be seen flowing downslope from the margin of snowpatches. The origin of this water may be from the melting of the snowpatch itself, from groundwater reaching the surface in slopes next to the snowpatch or from groundwater being forced to surface by obstructing permafrost
Permafrost () is soil or underwater sediment which continuously remains below for two years or more; the oldest permafrost has been continuously frozen for around 700,000 years. Whilst the shallowest permafrost has a vertical extent of below ...
. In areas with permafrost the active layer
In environments containing permafrost, the active layer is the top layer of soil that thaws during the summer and freezes again during the autumn. In all climates, whether they contain permafrost or not, the temperature in the lower levels of the ...
may be lacking under snowpatches, with the permafrost extending all the way to the firn at the base of the snowpatch.
See also
*Snow patches in Scotland
Long-lying snow patches in Scotland have been noted from at least the 18th century, with snow patches on Ben Nevis being observed well into summer and autumn. Indeed, the summit observatory, which operated from 1883 to 1904, reported that snow s ...
References
{{reflist Snow Glaciology