Wait, that would mean the ice had to have been advancing sometime during the decades since WWI.
Wait; no it wouldn't. It just means snow covered dead bodies. If you put markers at the front of glaciers, and they get wiped out by movement, the glacier is advancing. If you markers at the front, and then open ground appears between them and the glacier, it is retreating. It turns out people actually do that.
Retreat of glaciers since 1850
Other researchers have found that glaciers across the Alps appear to be retreating at a faster rate than a few decades ago. In a paper published in 2009 by the University of Zurich, the Swiss glacier survey of 89 glaciers found 76 retreating, 5 stationary and 8 advancing from where they had been in 1973. [18] The Trift Glacier had the greatest recorded retreat, losing 350 m (1,150 ft) of its length between the years 2003 and 2005. [18] The Grosser Aletsch Glacier is the largest glacier in Switzerland and has been studied since the late 19th century. Aletsch Glacier retreated 2.8 km (1.7 mi) from 1880 to 2009. [19] This rate of retreat has also increased since 1980, with 30%, or 800 m (2,600 ft), of the total retreat occurring in the last 20% of the time period. [19]
Morteratsch (right) and Pers (left) glaciers in 2005
The Morteratsch Glacier in Switzerland has had one of the longest periods of scientific study with yearly measurements of the glacier's length commencing in 1878. The overall retreat from 1878 to 1998 has been 2 km (1.2 mi) with a mean annual retreat rate of approximately 17 m (56 ft) per year. This long-term average was markedly surpassed in recent years with the glacier receding 30 m (98 ft) per year during the period between 1999–2005. Similarly, of the glaciers in the Italian Alps, only about a third were in retreat in 1980, while by 1999, 89% of these glaciers were retreating. In 2005, the Italian Glacier Commission found that 123 glaciers in Lombardy were retreating. [20] A random study of the Sforzellina Glacier in the Italian Alps indicated that the rate of retreat from 2002 to 2006 was much higher than in the preceding 35 years. [21] To study glaciers located in the alpine regions of Lombardy, researchers compared a series of aerial and ground images taken from the 1950s through the early 21st century and deduced that between the years 1954-2003 the mostly smaller glaciers found there lost more than half of their area. [22] Repeat photography of glaciers in the Alps indicates that there as been significant retreat since studies commenced. [23]
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