1 Background - mountain.PROJECTS

PETRI PELLIKKA AND KARI KAJUUTTI (ED)Table 5. Average thinning and average loss of ice thickness of Hintereisferner between 1953 and2003, and 1991 and 2003.Period Average thinning in water equivalent Average loss of ice thickness1953-2003 475 mm 0.5 m1991-2003 904 mm 1 m2003 1815 mm 2 m1500mean specific mass balance of Hintereisferner [kg/m 2 ]1000500mm water equivalent0-500-1000-1500-20001952/19531956/19571960/19611964/19651968/19691972/19731976/19771980/19811984/19851988/19891992/19931996/19972000/2001Figure 41. Mean specific mass balance of Hintereisferner 1952/53 to2002/03(1 kg /m 2 = 1 mm w.e.). The average over this period was -475 mm, from 1990/91 to 2002/03it was -904 mm w.e. and in 2002/03 it made a record of -1815 mm.w.e.The glacier – climate relationshipThere is general agreement among glaciologists and climatologists as well as among the nonscientificpublic that the glacier changes deserve highest attention, need to be monitored,explained and possibly projected into the future.The mass balance of a glacier is an account of gains and losses of ice, which both areintimately connected to climate, and to the topography of individual ice bodies. Glaciers ofsimilar shape will behave differently in different climatic regions like Scandinavia and theAlps, and glaciers of different shapes will behave differently although exposed to the sameclimatic conditions. The input or gain of the mass balance is made up by snowfall andsubsequent redistribution of snow by wind and avalanches which both tend to concentrate icein basins and cirques, while the loss is determined predominantly by melting in the summermonths.The topography of Scandinavian mountains favours ice to accumulate on plateaus where itforms ice caps like Svartisen, from which outlet glaciers descend to the valleys like61