Term: Water equivalent Class:  
 vernacular   (0%)
Created 6 June 2017
Last modified 6 June 2017
Contributed by GCW Glossary


Definition: A unit, in full the 'metre [of] water equivalent', that is an extension of the SI for describing glaciermass in specific units as the thickness of an equal mass having the density of water. 1 kg of liquid water, of density w = 1000 kg m-3, has a vertical extent of exactly 1 mm when distributed uniformly over a horizontal area of 1 m2. More formally, the metre water equivalent (m w. E.) Is obtained by dividing a particular mass per unit area by the density of water:1 m w. E. = 1000 kg m-2 / w . Water equivalents (m w. E.) Can be converted to kg m-2 by multiplying by the density of water, and to ice equivalents (m ice eq.) By multiplying by the density of water and dividing by the density of ice.  IHPGlacierMassBalance 

The liquid content of solid precipitation that has accumulated on the ground (snow depth). The accumulation may consist of snow, ice formed by freezing precipitation, freezing liquid precipitation, or ice formed by the refreezing of melted snow.  NOAA-NWS 

The depth of water that would result from the melting of the snowpack or of a snow sample. Thus, the water equivalent of a new snowfall is the same as the amount of precipitation represented by that snowfall.  AMSglossary