Globally, glacier mass loss has been significant over the past few decades. The European Alps is one of the regions where glaciers are shrinking most. On average, the observed Alpine ‘reference’ glaciers lost on average more than 24 m in thickness between 1997 and 2017, which corresponds to a mean annual mass loss of 1.2 kg per m2. In 2018, glaciers in the Alps lost another 1.5 m in ice thickness.

Seasonal observations from Glacier Monitoring Switzerland (GLAMOS) indicate that the Alpine glaciers started 2018 with snow cover that was up to 50% thicker than normal (compared with the period 1961-1990). However, the very long, warm and sunny summer turned the year into another one with extreme glacier mass loss for these Alpine reference glaciers. A similar or more negative average mass balance has only been recorded eight times since the 1960s.