1897 10 220 Professor Burton ascended by means of a moderate slope to the surface of the ablation area.
1961 3 850 The glacier [in a fjord] cannot reach equilibrium by changing the extent of its ablation area.
1991 Feb. (Analysis Educ. Suppl.) 3/1 The equilibrium firn line separates the accumulation area of the glacier from the ablation area and usually occurs where accumulation equals ablation at the end of the ablation season.