Glacier Mass Balance Calculator
Compute the annual specific mass balance of a glacier (in metres water equivalent) and the total volume change from accumulation, ablation and glacier area.
How to Use the Glacier Mass Balance Calculator
- Enter annual accumulation in m water equivalent.
- Enter annual ablation in m water equivalent.
- Enter the glacier area in km².
- Click Calculate.
Cas d'utilisation
- •Climate-change research.
- •Hydrology and downstream water supply.
- •Glaciology coursework.
Formule
Specific mass balance b = accumulation − ablation (m w.e./yr). Total volume change = b × A, converted from m·km² to km³ by dividing by 1000.
Questions fréquemment posées
What does "water equivalent" mean?
Snow and ice are converted to the equivalent depth of liquid water so that accumulation (snow of low density) and ablation (ice of high density) can be added consistently.
Positive or negative?
Positive mass balance means the glacier is gaining mass; negative means it is losing mass and retreating. Most of the world's glaciers have had negative balances since 1980.
How do I convert to ice thickness?
Divide the water-equivalent value by the average density ratio ≈ 0.9 (density of glacier ice / density of water). So 1 m w.e. corresponds to about 1.1 m of ice.