21 January 2010 | EN | 中文
Schild: We must be careful in making sweeping statements based on snout position and the state of glacial lakes
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.
To provide scientifically robust data we need to study glacier mass balance — the difference between snow accumulation and snow melt. But such data has not been forthcoming from the countries of the region. Studying the glaciers of the HKH has not been a priority for governments.
Take for example the report prepared by V. K. Raina, released by India's Ministry of Environment and Forests. Its findings are based on a number of expeditions but there is no mass balance data. The photographic observations of snout position must be qualified.
Since the 1950s, France and the United States have been conducting mass balance studies in India and Nepal. Meanwhile the Indian government began such studies in 2000 on three glaciers, I believe. Their findings have not been published, perhaps because of the controversy.
At ICIMOD we have a highly systematic overview based on remote sensing. But our information is not comprehensive. In collaboration with UNESCO and the Institute of Tibetan Plateau Research, we are conducting training on mass balance studies for regional representatives.
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.
How does ICIMOD view the current dispute over the IPCC prediction of 2035?
About a year-and-a-half ago, I participated in a seminar where this figure was launched. And I said: "I would not bet a plate of Swiss chocolate that this figure is correct". It has no solid basis, there are many factors at play. Take for instance the situation in northern Pakistan. Similarly there is more precipitation in the Tibetan plateau, probably because of climate change. This might mean more precipitation in the winter which might change the glacier, possibly making it advance.
In the same report, the IPCC made another prediction. They said that the surface of the HKH glaciers would decrease from 500,000 square kilometres to 100,000 square kilometres. Now, our studies suggest that the actual surface of these glaciers is in fact between 108,000 to 112,000 square kilomoetres [not 500,000]. This is our current understanding.
These numbers indicate the way in which some IPCC people seem to be working. Unfortunately, the debate on this figure is now politicising the larger issue.
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.
What is the way forward?
In the next few days, you will see most international organisations making statements on the debate. But they have no direct scientific information either. Many of these agencies will conclude by saying more research is needed, which is a healthy position to take. But it is very important that national agencies take responsibility for this research. The international agencies will start projects, but these will only last for two or three years. We need strong, regional, long-term efforts to gather information.
The good news is that countries like China, Indian and Pakistan have begun to clearly demonstrate a will to work on this, both in terms of human resources and funds. ICIMOD will conduct its work using the same methodologies and databases as these governments so that we can share information. At the moment, we are studying critical glacial lakes, which increase vulnerabilities downstream in Nepal. These findings will be published in two months. We encourage similar studies in other countries in the region.
There are a number of good information-gathering initiatives in the works. One of these is a discussion to launch an international Third Pole (Tibetan plateau) programme, which emerged from a congress in Beijing last year. ICIMOD is considering how the region can be involved in this.
The positive side of all this debate is that there is now an understanding that the Himalayan glaciers do not affect just the mountain communities. Rather, they impact the entire Gangetic basin — which spans Bangladesh, China, India and Nepal, supporting a population of almost 500 million people —which is one of the most irrigated landscapes in the world, and also highly populated. We need to keep in mind what needs to be done in terms of adaptation locally, and a bottom-up approach is a necessary part of this.
Could you expand on the importance of paying attention to adaptation locally?
Having dealt with issues like excess precipitation or GLOFS, mountain communities have traditional adaptation mechanisms. We need to study these and see how they can be adjusted with new scientific knowledge. As a part of this effort, ICIMOD is looking at five watersheds in four countries, with a special view to people's reaction to water stress, meaning too much or too little water. This report is now on our website.
We currently also have a team in Chengdu, China, studying the Kosi basin there. We want a more systematic view of water basins, in addition to traditional practices, which are of course important. Government policy is also important; for instance, hydroelectricity and its monetary aspects will also be affected by climate change.
Would you like to add anything else on the issues at hand?
The question is what the positive and negative effects of this debate are. The positive aspect is that there is today an awareness that was lacking five years ago. And this issue of awareness has not been addressed, even in a forum such as the Copenhagen climate change meeting in December.
The negative aspect is that we are going forward without robust facts and figures. As things stand, we have the sceptics, the activists and in the middle, I suppose, the realists. The debate on facts and figures is used to conduct the global debate on mitigation.
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