By IANS,
Sydney : Glaciers in the southern Alps have lost 2.2 billion tonnes of permanent ice in a year since April 2007, the fourth highest annual loss since monitoring began.
For the past 32 years, the New Zealand based National Institute of Water & Atmospheric Research (NIWA) has been surveying 50 glaciers in the southern Alps, using a small fixed wing aircraft, to record the height of the snow line at the end of summer
NIWA principal scientist Jim Salinger said photographs taken on this year’s survey showed the glaciers had lost much more ice than they had gained during the past glacier year, reports Sciencealert.com.
“As a result of La Niña conditions over New Zealand, more easterlies, and warmer than normal temperatures, there was less snowfall in the southern Alps and more snowmelt.
“The higher the snow line, the more snow is lost to feed the glacier. On average, the snow line this year was about 130 metres above where it would need to be to keep the ice mass constant,” Salinger said.
Salinger said these results match trends of ice mass lost globally. International monitoring of mountains glaciers by the World Glacier Monitoring Service in Switzerland shows most glaciers are retreating.
Of the glaciers where continuous data is available, the mean annual average loss in ice thickness since 1980 is close to half a metre per year.