Alps — The impacts of climate change in Europe today

'Yesterday, I came back from leading a climb on the Matterhorn in Switzerland. We used the Hornli ridge, the famous route first climbed in 1865. I go there every summer. These well-used routes are becoming dangerous and several have been shut. The permafrost, which has held the rock together for hundreds or thousands of years, is melting. It melts during the day and freezes at night and this is causing the rock to crumble. This is happening at higher altitudes every year — it's moving up the mountains.'

Sebastian Montaz lives in Saint Gervais, a village in the Chamonix region of France. A mountain guide and ski instructor, he grew up in the French Alps but guides climbers and skiers across the Alpine region.

'Mountains normally change slowly. But here in the Alps we see the changes almost as each season changes. It has altered dramatically since I was a boy and who knows what the Alps will be when my daughter is grown up.'

'For the past five years, from June to July, it has not been possible to carry out mixed climbing where you climb on snow and ice. Now it's not safe from June until the end of September. Last winter we had the best snow in nine years but winters like that are now the exception,' says Sebastian.

Climate change is affecting the Alps from the composition of the permafrost that holds the rocks together, to the volume and quality of snow. Glaciers are retreating and ice and snow bridges are disappearing. The art of guiding in the mountains is changing as traditional routes become unsafe. Some glaciers, that could be traversed five years ago, have changed. The ice is gone and the rock underneath is exposed.

An icon of Europe

The Alps are an iconic symbol of Europe. One of the continent's prime tourist destinations, the range provides much more than holiday destinations. Forty per cent of Europe’s fresh water originates there, supplying tens of millions of Europeans in lowland areas. No wonder the Alps are sometimes called the 'water towers of Europe'.

This fresh water is vital, not only to the eight Alpine countries but a huge part of continental Europe. A recent EEA report, 'Regional climate change and adaptation — The Alps facing the challenge of changing water resources', considers the effects of climate change on fresh water supply and demand in key Alpine regions.

The Alps — a changing ecosystem

Mountains normally change slowly, as Sebastian Montaz observes. But the Alpine climate has changed significantly in the last hundred years, with temperatures increasing 2 °C: twice the global average. And Alpine glaciers are melting as a result. They have lost about half of their ice volume since 1850 and loss rates have accelerated strongly since the mid-1980s.

The snowline is also rising and patterns of precipitation (rain, snow, hail and sleet) are also changing. A large number of medium-size and small glaciers are likely to disappear within the first half of the century. It is estimated that regions currently receiving snowfall will increasingly experience winter rain instead, leading to fewer days with snow cover. This is affecting the way the mountains collect and store water in winter and distribute it again in the warmer summer months. Thus run-off is expected to increase in winter and decrease in summer.

The cycle of water and climate change

Water is collected and stored as snow and ice in glaciers, lakes, groundwater bodies and soil in the Alps during winter. It is then slowly released as the ice and snow melt throughout spring and summer, feeding rivers such as the Danube, Rhine, Po and Rhone, all of which have headwaters in the mountains. This makes water available when supply is dropping in the lowlands, and when demand is highest. 

The delicate interactions that underpin this ancient process of storage and release are now under threat from climate change. How will the Alpine ecosystems be affected by climate change? How will ecosystems services change? What can we do?

An ecosystem service under pressure

The Alpine 'water towers' are extremely sensitive and vulnerable to changes in meteorological and climatic processes, landscape and human water use. Alterations can affect the quality and quantity of water supplied to tens of millions of Europeans.

Climate change threatens to alter the Alpine 'water cycle' drastically. Changes in precipitation, snow-cover patterns and glacier storage are expected to alter the way water is transported. That means more droughts in summer, floods and landslides in winter, and greater variability in the water supply throughout the year. Water quality will also be affected.

Water shortages and more frequent extreme events, combined with ever increasing water demand (for irrigating agriculture or tourist influxes, for example), are likely to hurt ecosystem services and economic sectors. Households, agriculture, energy production, forestry, tourism, and river navigation will all suffer. This may exacerbate existing water resource problems and could lead to conflict between users both in the Alpine region and elsewhere. Southern Europe, in particular, is likely to face more frequent droughts.

Water, a resource often taken for granted, is taking on a new value in the context of a changing climate.

On the streets of Vienna

'The water we get in Vienna travels at least 100 kilometres from the springs in the mountains,' says Dr. Gerhard Kuschnig, head of Spring Protection with the City of Vienna Waterworks. Dr. Kuschnig is several hundred kilometres away from the Alpine home of Sebastian, the mountain guide. But climate change is on his mind too.

'For now, there are no real problems with the quantity or quality of the water but the future is uncertain. Managing climate change means managing uncertainty. We want to make sure we are asking the right questions,' Dr. Kuschnig adds.

Two million people in the cities of Vienna and Graz and the surrounding areas depend on one section of the Austrian Alps for water. Therefore fresh water springs in the region are legally protected. The water aquifers (a body of saturated rock through which water can easily move) in these mountainous areas are extremely vulnerable due to the geological make‑up of the rock, the climate and land‑use activities, which together substantially influence the quality and quantity of the water available.

In adapting to climate change, one of the key challenges for this region is protecting the quantity and quality of fresh water. High‑quality water can only be assured in the long term by protecting the land through which water travels. Changes to the land, including new farming practices and construction, for example, all affect water quality and quantity. Vienna has been protecting the nearby mountain springs for more than 130 years, gradually gaining ownership of vast territories in the water protection and sanctuary areas. The water protection zone covers an area about 970 km² located in Styria and Lower Austria.

The water cycle

'The water runs through the surface layers of the rock, circulates inside the mountain and after reaching impermeable layers drains to springs, whereby it returns to the surface,' explains Dr. Kuschnig.

'The time span between infiltration (entering the ground) and discharge (returning to the surface via a spring) of water after a rainfall event is very short. Extreme events, such as heavy rainfall or rapid snow melting, mobilise large amounts of sediment which affect the water quality. Large amounts of sediment often cannot be filtered out within the short time before discharge. The likelihood of extreme weather events increases with climate change.'

Climate change

Changing climate conditions in the region, such as rising temperature, will influence the availability and quality of water directly through enhanced evaporation and changes in precipitation. Climate change is also causing indirect effects on water resources by altering vegetation.

Two-thirds of the protection zone is covered with forests. Like agriculture, the region’s forests are managed with the aim of protecting drinking water in mind. 'Our biggest threat at the moment from climate change is increased erosion as it threatens the forests. Without trees and proper foliage the soil will be washed away and it’s the soil that cleans the water. Temperature increases will mean new types of trees. Climate change equals uncertainty, new factors — and that is always a risk,' says Dr. Kuschnig.

Adaptation activities and experiences

In the meantime, education is an important task for the water authority. A water school has been teaching local children for the past 13 years about the importance of water and the landscape that provides it. Regular trips are offered to the mountain springs so that students can better understand where their water comes from. Information is also important for the farming community high up in the Alpine pastures. They also have a responsibility to protect land around the springs, especially from animal effluent.

Vienna Water is already involved in projects that bring together other actors in the water world to discuss impacts and adaptation to climate change. For example, a project called CC-WaterS brings together 18 organisations from eight countries to share experiences and discuss common adaptation approaches.

Adaptation policy

'Policy measures related to climate change adaptation are often drafted in response to extreme weather events that motivate demand for action,' says Stéphane Isoard, from the Vulnerability and Adaptation team at the EEA.

'The heatwave of 2003 is a case in point. However, strategies for adaptation that are based on more systematic analysis of vulnerable regions, sectors and people must be thought of now and implemented soon, if they are to be robust and effective in the future for coping with unavoidable impacts of climate change. Adapting to climate change and water-resource issues requires local management within a larger regional, national and EU context,' he says.

A key element will involve effective river‑basin management across national boundaries. For instance, there has been very little cooperation so far between countries in managing water shortages along river basins originating in or fed by the Alpine region. The EU is in a strong position to assist this process by improving the conditions for cooperation.

5. The Water Framework Directive

6. The Water Framework Directive