The Alps are known as “Europe’s water tower”.
Their glaciers provide 40 percent of Europe’s fresh water.
Pure and abundant, alpine streams fill major rivers, including the Danube, Rhine, Po, and Rhone, making irrigation and transportation possible in large parts of Europe.
But these glaciers are facing an uncertain future, as studies show that temperatures in the Alps are increasing at a rate that’s more than twice the global average.
Umberto Morra di Cella is a technical researcher looking to make that furture less uncertain. He told us:
“We’re in the Aosta Valley, in the north-western corner of Italy. Here’s a site where we have placed a meteorological station at an altitude of 3100 meters that allows us to collect data used to drive the model simulations of glacier and snow dynamics.”
Scientists need to know the quality and quantity of snow covering the hard-to-access mountain tops.
Here in the Aosta Valley, measurements are collected by a network of automated weather stations, managed by the regional environmental protection agency ARPA, as Morra di Cella explains:
“The relevant parameters that are being measured are the thickness of the snow, air temperature, solar radiation, wind speed and direction and the surface temperature that is being detected by this infrared thermometer.”
Analysing the data results in the so called ‘snow-water equivalent,’ accurately measuring the frozen water supply before it melts into rivers.
“This box is sending collected data via mobile phone networks – GPRS and GSM. That allows us to monitor in real time all the parameters we’re interested in,” says Morra di Cella.
All the weather stations in the regional network are powered by solar panels, and automatically transmit measurements to local research and meteorological bureaus.
Sara Ratto, a geologist at the Centro Funzionale in Valle d’Aosta describes what they do there:
“We are at the regional “Functional Centre,” which makes forecasts of the weather and natural emergencies, like floods and landslides. We also prepare a bulletin summarising rain and river levels in the region.”
The narrow valleys of the alpine region are threatened by natural hazards, often linked to the changing climate.
According to recent research, the next few decades will make snow melt earlier, increasing the likelihood of floods and avalanches in winter and spring.
Scientists here are busy building models to make early predictions of dangerous developments.
Hervé Stevenin, a hydrologist at the Functional Centre told us:
“We’re using satellites as instruments for measuring the extent of the snow cover, and the data on snow density and water content provided by ARPA. We use all that data, together with our meteorological forecast, in a hydrological computer model to transfer that water into hydrological networks and estimate the flow levels in the most sensitive areas. This way we can see where there’s a threat to local communities – and warn them of probable floods.”
This study is a part of a major European Union research project, ACQWA, run by more than three dozen scientific partners in several regions in and outside Europe.
The project’s goal is to assess the impact of climate change- both negative and positive – on water resources in mountainous regions.
Automatic weather stations are not the only method of remote monitoring used in the Italian Alps. This site is situated under an unstable hanging glacier. Large blocks of ice sometimes fall down, threatening locals and tourists – but, of course, climbing up the glacier to take measurements would be too dangerous.
Instead, the “Secure Mountain Foundation” – another participant in the ACQWA project – is studying the perilous mass of ice using its three-dimensional computer double.
Fabrizio Diotri is an environmental engineer working on the project.
“How did we make this model? We used close-range photogrammetry – we took several pictures of the hanging glacier from different angles, from a helicopter, and then reconstructed the three-dimensional structure of this object,” he says.
As a result, all the measurements and dissections are taken quickly and accurately with a simple click of the mouse button.
Still, security issues are not the only climate-related concern that needs to be examined. Local economies are also under threat. What will happen to the famous ski resorts when the Alps get warmer?
Prognoses are troubling: most of the Alpine glaciers could keep melting until the end of the century, endangering the lives of millions of people living in vast lowland areas.
Martin Beniston, an ACQWA project coordinator at the University of Geneva paints an unsettling picture:
“The best case scenario is that until 2100 about 50% of glaciers will disappear, and the worst-case scenario is about 90%. Obviously, that will completely change the morphology of what we’re calling “Europe’s water tower” – the Alpine domain. We already have certain conflicts of interests concerning water usage between energy, tourism and agricultural sectors, and obviously there’s a risk of their aggravation, if water becomes more scarce.”
One example is neighbouring Switzerland, which relies on hydropower stations for 60% of its energy supply. This clean and renewable energy source may be severely affected by projected water shortages.
The narrow underground tunnels lead us to the foot of 220-metre high Verzasca Dam nearby Locarno.
The concrete arch, made famous in one of the James Bond movies, holds 100 million cubic meters of water. It generates over 100MW of electricity, supporting the local power network at periods of high consumption.
How dramatically this industry will suffer from changing precipitation rates is also a subject of scientific examination.
For Franco Romerio, a researcher at the University of Geneva’s Institute for Environmental Studies we could see the consequences in our homes:
“We need to understand the link between water running in these mountains and the electric current in our homes. So the climate change is bringing a major change indeed – the problem is that there will be more water in spring, but in July and August its levels will drop, and that will impact production on hydropower plants of this type – so the whole energy sector security needs to be rethought.”
The international project is due to present its findings by 2013. Researchers have little doubt that water in many sensitive regions will become rarer because of reduced snow and ice amounts over the next few decades. Receding glaciers will pose multiple threats to regional economies and the safety of local communities. However, knowing what to expect should make it easier to adapt to changing environment.