Work

Analysis of the mass balance time series of glaciers in the Italian Alps

Year: 2016

Type: article

Abstract: . This work presents an analysis of the mass balance series of nine Italian glaciers, which were selected based on the length, continuity and reliability of observations. All glaciers experienced mass loss in the observation period, which is variable for the different glaciers and ranges between 10 and 47 years. The longest series display increasing mass loss rates, that were mainly due to increased ablation during longer and warmer ablation seasons. The mean annual mass balance (Ba) in the decade from 2004 to 2013 ranged from −1788 mm to −763 mm w.e. yr−1. Low-altitude glaciers with low elevation ranges are more out of balance than the higher, larger and steeper glaciers, which maintain residual accumulation areas in their upper reaches. The response of glaciers is mainly controlled by the combination of October–May precipitation and June–September temperature, but rapid geometric adjustments and atmospheric changes lead to modifications in their response to climatic variations. In particular, a decreasing correlation of Ba with the June–September temperature and an increasing correlation with October–May precipitation are observed for some glaciers. In addition, the October–May temperature tends to become significantly correlated with Ba, possibly indicating a decrease in the fraction of solid precipitation, and/or increased ablation, during the accumulation season. Because most of the monitored glaciers have no more accumulation area, their observations series are at risk due to their impending extinction, thus requiring a soon replacement.

Source: The cryosphere

DOI: 10.5194/tc-10-695-2016