Tentative figures for the year 2007 indicate a further loss of average ice thickness from more than 80 glaciers of roughly 0.67 meter water equivalent (mwe). Some glaciers in the European Alps lost up to 2.5 wme.

Glaciers with available long-term observation series around the world (30 glaciers in 9 mountain ranges) show a thickness reduction of 1.3 and 0.7 meters water equivalent (mwe) during the hydrological years 2006 and 2007, respectively.

The new data continues the global trend in accelerated ice loss over the past few decades and brings the cumulative average thickness loss of the reference glaciers since 1980 at almost 11.3 mwe.

The average ice loss in 2007 was not as extreme as in 2006, but there were large differences between mountain ranges. Glaciers in the European Alps lost up to 2.5 meters water equivalent of ice, whereas maritime glaciers in Scandinavia were able to gain more than a meter in thickness. However, 2007 is now the sixth year of this century in which the average ice loss of the reference glaciers has exceeded half a meter. This has resulted in a more than doubling of the melt rates of the 1980s and 90s.

—Michael Zemp, glaciologist and research associate of the WGMS

Glaciologists express the annual mass balance, i.e. the gain or loss in thickness, of a glacier in ‘meter water equivalent’ (mwe). This standardized unit takes the different densities of change measurements in ice, firn and snow into account. One meter of ice thickness corresponds to about 0.9 mwe.