A new study of 100 glaciers has shown that ice loss in 2006 was unprecedented. Between 1980 and 1999, average rates of loss were 30cm per year. In 2006, 1.5 metres were lost.
Overall, the data is not encouraging:
During 1980-1999, average loss rates had been 0.3 metres per year. Since the turn of the millennium, this rate had increased to about half a metre per year.
The record annual loss during these two decades – 0.7 metres in 1998 – has now been exceeded by three out of the past six year (2003, 2004 and 2006).
On average, one metre water equivalent corresponds to 1.1 metres in ice thickness. That suggests a further shrinking in 2006 of 1.5 actual metres and since 1980 a total reduction in thickness of ice of just over 11.5 metres or almost 38 feet.
Glaciers play a critical role in the fresh water cycle. They help to conserve winter snowfall, contributing to river flow in summer. They also affect patterns of downwind precipitation, especially past the Himalayas.
In his infamous address to the White House Press Corps, Stephen Colbert joked about how “your grandchildren will have no idea what a glacier is.” If these trends persist, that might be an accurate prediction.