An expert speaks on the glacier retreat debate

SciDev.net: The dispute about whether the Himalayan glaciers are shrinking has highlighted just how much more there is learn about the behaviour of glaciers (see Glacier dispute reveals holes in research). SciDev.Net caught up with Andreas Schild, director-general of the International Centre for Integrated Mountain Development (ICIMOD), based in mountainous Nepal, to find out what kind of research will yield those answers.

What do ICIMOD studies reveal about the behaviour of the Himalayan glaciers?

The glacial retreat debate has been too simplified. The data that is discussed usually deals with the information on the terminus, or snout (the end of a glacier) based on remote sensing or ground observation. A large majority of glaciers are in retreat, defined as the shifting of the snout. But we do not have information on how many metres most of the Hindu-Kush-Himalayan (HKH) glaciers are retreating or expanding by, or how much expansion or decrease in surface ice there has been….

…What, in ICIMOD's view, is the most cautious interpretation of the Himalayan glacier data?

We could agree that the vast majority of the HKH glaciers are retreating in terms of the snout position. It is also likely that there is ice mass loss in the glaciers below and altitude of 5,400 metres. But it is very difficult to conduct observations of glaciers in valleys. However, in northern Pakistan, glaciers are advancing in terms of the snout position and probably also in terms of ice mass. Winter precipitation in terms of snow has also intensified in northern Pakistan, probably because of climate change. Ultimately, there is no systematic data….

….What are the implications of the data debate for the people of the region?

The war among scientists does not affect people. What does affect them are the changes that are already taking place. These changes include alterations in rainfall patterns as well as glacial lake outburst floods (GLOFS), which occur when bodies of glacial melt water burst their banks….

View of Himalayan peaks near Kanchenjunga Base Camp, from the Zemathang glacier. Shot by Amar, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License