Graph of the Day: Annual Mass Balance of Glaciers, 1980-2008
Preliminary mass balance values for the observation period 2007/08 have been reported now from more than 90 glaciers worldwide. The mass balance statistics (Table 1) are calculated based on all reported values as well as on the data from the 30 reference glaciers in 9 mountain ranges (Table 2) with continuous observation series back to 1980. The average mass balance of the glaciers with available long-term observation series around the world continues to decrease, with tentative figures indicating a further thickness reduction of 0.5 metres water equivalent (m w.e.) during the hydrological year 2007/08. The new data continues the global trend in strong ice loss over the past few decades and brings the cumulative average thickness loss of the reference glaciers since 1980 at about 12 m w.e. (see Figures 1 and 2). …