Editing Cryosphere (section)

=== Snow cover ===
{{Main|Snow}}
[[File:Snow-covered_fir_trees.jpg|thumb|Snow-covered trees in [[Kuusamo]], [[Finland]]]]
[[File:Long Mynd snowdrift.jpeg|right|thumb|Snow drifts forming around downwind obstructions]]
Most of the Earth's snow-covered area is located in the [[Northern Hemisphere]], and varies seasonally from 46.5 million km<sup>2</sup> in January to 3.8 million km<sup>2</sup> in August.<ref name="robinson">Robinson, D. A., K. F. Dewey, and R. R. Heim, 1993: Global snow cover monitoring: an update. Bull. Amer. Meteorol. Soc., 74, 1689–1696.</ref>

[[Snow]] cover is an extremely important storage component in the water balance, especially seasonal [[snowpack]]s in mountainous areas of the world. Though limited in extent, seasonal [[snowpack]]s in the [[Earth]]'s mountain ranges account for the major source of the runoff for stream flow and [[groundwater]] recharge over wide areas of the midlatitudes. For example, over 85% of the annual runoff from the [[Colorado River]] basin originates as snowmelt. [[Snowmelt]] runoff from the Earth's mountains fills the rivers and recharges the aquifers that over a billion people depend on for their water resources.{{citation needed|date=September 2023}}

Furthermore, over 40% of the world's protected areas are in mountains, attesting to their value both as unique [[ecosystem]]s needing protection and as recreation areas for humans.{{citation needed|date=September 2023}}