Martin Price : "All glaciers are already affected by climate change."

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Professor Martin Price, Director of the Centre for Mountain Studies at Perth College, University of the Highlands and Islands (United Kingdom) takes a critical look at the consequences of climate change for mountain ecosystems.

Interview by Agnès Bardon, UNESCO Bureau of Public Information.

Are there already any clear signs of the impact of climate change on mountain ecosystems?

Yes, on a number of different levels. In fact, mountains are particularly useful sites to study the impact of climate change on the environment. The first tangible indicator is the melting of glaciers. This phenomenon is already clearly happening in places like the Glacier National Park in the Rockies (USA), which is also a biosphere reserve, and the summit of Kilimanjaro (Tanzania), which is on the World Heritage List. But glaciers everywhere are being affected, and they have been shrinking for several years.
The second observable phenomenon started at the beginning of the 20th century and is still continuing today. It is particularly evident in the Alps and involves the migration of certain species of plant, which are now found at altitudes at which they were never able to grow before, because of the harsh climate.
Finally, some species of plant and animal are threatened with extinction, while others have already disappeared, like the Golden Toad, which used to live in the high altitude tropical forests of Costa Rica. According to WWF and the US NGO Conservation International, mountain-dwelling species are among those in the greatest danger. These are all concrete examples of the impact of climate change on the mountain environment.

How might the situation develop in the future?

It is always difficult to make these kinds of predictions. It is even more difficult in this case, as we have little data on the evolution of temperatures at mountain summits, because measurements are usually taken in the valleys and not at high altitude. Even so, we can predict that warming will continue, with further melting of glaciers. In the short term, of course, this will mean greater reserves of fresh water, but, in the long term, it will mean that these supplies will dry up for local populations. We can also predict an increase in the number of extreme events, like glacial lake outburst floods (GLOFs), mudslides and avalanches. There is also a risk that certain diseases, like malaria, will spread to high altitude regions where they have not previously been found.

Which regions are most at risk? Are preventive measures already in place?

Mountains in tropical and sub-tropical regions definitely face the greatest risk, because life is generally better there than in the adjacent valleys, and they usually have fertile soil. This means that they are densely populated. Any hazardous events happening in these regions will therefore have far-reaching effects. Regular measurements are already being taken of the levels of glacial lakes to prevent flooding. And, in some regions, foresters have already started to plant tree species that are able to survive and reproduce in a more clement environment. Since it is not possible to prevent climate change, it is important that mountain populations have the capacity to adapt to the new conditions.

To what extent can biosphere reserves play a role in impact assessment??

They constitute a unique network, representing a great diversity of mountain ecosystems spread over different latitudes and subjected to a variety of climates ranging from humid-maritime to dry continental. The central areas of these sites are little affected by human activity and, as a result, are exceptional sites for carrying out observations. The GLOCHAMORE research strategy, which was drawn up by about 100 scientists and biosphere reserve managers and launched in 2005, could be an additional tool for understanding the phenomena affecting mountainous regions. Its purpose is to plan and implement research activities. It covers areas as varied as climate, biodiversity, risk prevention, mountain economy and changes in land use.

• 14-11-2008