|Adaptation strategies in montane regions are key to water security|
The important role played by mountains in freshwater supply and regulation justiﬁes their reputation as Water Towers of the world. They are home to the headwaters of the world’s major rivers, and about 40% of the population depends indirectly on mountain resources for water supply, agriculture, hydroelectricity and biodiversity. Mountains are among the most sensitive ecosystems to climate change and are being affected at a faster rate than other terrestrial habitat, putting their integrity and the services they provide at risk. In view of the urgent need for adaptation strategies and policies, an exhibition and High-level Panel Session was organized during UNESCO’s General Conference to share experiences, views and recommendations on coping with climate change impacts on water resources in mountainous areas.
Glaciers and snow resources act as critical buffers to the variability of water in time by providing water during the dry season, and by storing water in years of high snowfall and releasing it in hot and dry years. In other words, they store water when it is less needed, and release it when it is most needed. But climate change translates into changing precipitation patterns and temperatures, and glaciated regions are more vulnerable as temperatures are rising faster at higher elevations.
The panel discussion highlighted that glacier retreat is one of the most significant environmental changes observed in mountainous regions all over the world –in the Andes, Pamir, Tian Shan, Hindu Kush-Himalayas and Europe, where glaciers have retreated dramatically in a few short decades. Rising temperatures, changing precipitation patterns and black carbon depositions are currently under discussion by scientists as major causes of the strong glacier melt.
This is the most visible indicator of climate change, as shown in an exhibition organized jointly by the International Hydrological Programme and the Man and Biosphere Programme. Glacier melt leads to higher risks of natural hazards, especially floods and landslides that pose a threat to the often vulnerable populations in those regions.
There is a clear impact on river flows and their variability, affecting the water supply downstream. Biodiversity is also impacted, affecting mountain ecosystems such as montane forests, cloud forests, wetlands and grasslands that play vital roles in water storage and supply, erosion prevention, reduction of peak ﬂows, reduction of ﬂood risks, water ﬁltering and improvement of water quality. In other words, we know that water availability and quality is changing in these regions, and fast. »But we need to know more, much more about these impacts«, said Ms Irina Bokova, Director General of UNESCO, in her opening remarks. »This is why monitoring glacier mass balance and snow cover is so important.«
The panel made a case for increased collaboration between the scientific community and policy makers to develop science-based adaptation options and strategies. The panel deemed essential that the International Hydrology Programme (UNESCO-IHP), together with UNESCO’s Category 2 centres and in close cooperation with scientists worldwide, should continue to play a vital role to establish a scientific and technological base for the sustainable management of water resources threatened by global climate change.
Several experts called for cooperation at the regional level, to develop shared monitoring systems that would provide information on glacier mass dynamics and early warning systems to forecast floods or droughts. Inter-regional cooperation would also be helpful to share experiences and good practices between mountain regions.
In the coming years, UNESCO-IHP will focus on »Water Security: Responses to Local, Regional and Global Challenges« (Phase VIII, 2014–2020). Together with relevant specialized Category 2 Centres, the Programme will work to create a momentum for regional scientific collaboration particularly in monitoring glaciers, snow and permafrost conditions and evaluating the implications of climate change on water resources and will provide feedback to develop appropriate adaptive strategies that countries need.