Glossary

Glossary

Albedo Measure of reflectivity. The ratio of reflected to incoming solar energy.
Snow Water Equivalent The amount of water contained within a snowpack. The depth of water that would theoretically result if you melted the entire snowpack instantaneously. SWE = snow depth * snow density (in %).
Local Solar Noon Local time of day when the sun is at its lowest zenith angle (e.g., highest in the sky). NOAA solar noon calculator: http://www.esrl.noaa.gov/gmd/grad/solcalc/
Solar Zenith Angle Angle measured from directly overhead to the location of the sun in the sky. Solar zenith angle of 0° indicates the sun is directly overhead; high solar zenith angle means the sun is located closer to the horizon. Mid-winter solar zenith angle at local solar noon reaches a maximum of 68° at the northernmost station. See diagram of solar zenith angle, azimuth, and elevation angles.
Snow Density The mass (kg) of a snow sample divided by the volume (m3) of a snow sample, typically ranging from 100 kg/m3 (fresh snow) to 500 kg/m3 (compacted, wet snow). Can also be expressed as a percentage (%) by dividing the snow density in kg/m3 by the density of liquid water (1000 kg/m3). Example: a snow density of 300 kg/m3 is equivalent to snow density of 30%.