Vulnerabilities Switzerland

Buildings

With global warming, the demand for air conditioning will increase. Appropriate construction methods for new buildings and adequate renovation of existing buildings make it possible to cool buildings energy-efficiently and thereby minimise the costs. Overall the savings in heating energy are expected to be larger than the additional energy demand for cooling (3).

The possible increase in floods, heavy precipitation, storms and hail events can endanger buildings and lead to great financial damage. The changing risks require the adaptation of building regulations. The expected increase in winter precipitation may cause static problems for roofs at elevations where precipitation falls as snow. Too high snow loads can result in extensive damage or, in the worst case, even the collapse of the roof (3).

The risk of avalanches may change with global warming but it is unclear whether they will become more or less frequent (3).

The changing climate has the potential regionally to increase premature deterioration and weathering impacts on the built environment, exacerbating vulnerabilities to climate extremes and disasters and negatively impacting the expected and useful life spans of structures (4).  

Infrastructure

Small increases in climate extremes above thresholds or regional infrastructure ‘tipping points’ have the potential to result in large increases in damages to all forms of existing infrastructure nationally and to increase disaster risks (5). Since infrastructure systems, such as buildings, water supply, flood control, and transportation networks often function as a whole or not at all, an extreme event that exceeds an infrastructure design or ‘tipping point’ can sometimes result in widespread failure and a potential disaster (6).

Melting permafrost destabilises ground conditions. This may affect infrastructures which are placed at high altitude. Buildings, masts of cable cars, avalanche barriers etc. are vulnerable when anchored in permafrost ground (2). However, initial surveys indicate that to date the number of installations directly affected by this phenomenon is quite limited (1).

Shipping

Climate change will have an impact on discharge. Today, the Rhine has a stabile discharge thanks to meltwater supply and precipitation in the Alps in spring/summer, and precipitation in lower lying areas in autumn/winter.
The meltwater of the winter snow cover and of glaciers is currently an important source for regular discharge at times of low precipitation. This balancing effect will continually decline with the melting of glaciers. The probability
of extended periods with unusually low water levels will increase by 2050. This will probably affect the temporal reliability of Rhine shipping (3).

15% of the amount of foreign trade is transacted using Rhine ports; for mineral oil products this is as high as 35%. In 2003, transported tonnage and transport performance showed a decrease of 5.8 and 9.9%, respectively. This decrease was primarily due to the low water levels in the second half of the year (3).

Rail transport

The effects of climate change on the rail network can be attributed primarily to the possible increase in extreme weather events. Heavy precipitation events put line stability at risk, and storms and heat waves can cause damage to overhead contact wires and rails... The possibility that railway stretches built on artificially cut-out slopes in the midlands and the foothills of the Alps will slide away should not be underestimated. There, heavy precipitation may also lead to water logging, instability and hence to landslides. Above the snow line, larger winter precipitation amounts may result in an increase in the danger of avalanches or blocking of infrastructure (switch blocking, restricted visibility, snow piles on the lines) (3).

The heat-wave summer of 2003 showed the consequences of high temperatures on slope stability. In the course of that hot summer, a great number of rockfalls and rock avalanches were observed in the entire alpine region, in
particular at higher elevations and on north facing slopes. As areas with permafrost are very often located outside of settlement and infrastructure areas, the future risk is also limited (3).

The increase in summer temperatures affects the railway system. High temperatures lasting for days can result in lateral displacement of the tracks. This happens because expansion of the tracks due to the heat is blocked by the seamless welding (3).

Road transport

Similar to the railway system, the road network is also primarily at risk from extreme events. With preventive measures for new hazards and with adaptations in road making, disturbances and risks to road traffic will be kept largely constant (3).

If rivers and lakes burst their banks, excessive volumes of water may cause undercutting or, in flatter areas, floods. In mountain areas, heavy precipitation often results in landslides and mudflows. ... Just like the railway system, the road network may be affected by avalanches or avalanche risk. In conjunction with climate change, the risk will possibly increase at higher elevations, where larger precipitation amounts may fall as snow in winter. ... The risk of fallen trees by winterstorms is currently small and should not increase substantially in the future.

A related problem is the frequency of rock fall and debris flows which will increase due to the combination of melting glaciers, melting permafrost, rising snow line and more intense precipitation. This may present an additional risk to climbers and hikers at high altitudes. Furthermore, the increasing threat to traffic routes from extreme events may lead to more instances where access to individual tourist resorts in the Alps is limited (1).

Snow and ice can cause major problems for communities due to closed roads or airports. For future decades less snowfall is projected in the Alps. This will very likely reduce road accidents, temporary airport closures as well as the costs for winter road maintenance at the end of the century (7). 

Adaptation strategies Switzerland

Buildings

With global warming, the demand for air conditioning will increase. In new buildings, appropriate construction methods can make the installation of airconditioners superfluous. Architectural measures can make a considerable contribution, for instance sun protection, room depth, window size and orientation, and architectural landscape elements, such as trees, lawns and water features. In residential buildings, adequate construction
usually avoids the need for cooling devices, in particular because of the nighttime cooling through opening the windows (3).

The expected increase in intensity and frequency of extreme weather events endangers damageable elements of the building shell. Today’s construction standards, which are based on the mean climatic values of past observation periods, need to be adapted to the future climate. In order to minimise the risk of roof collapse, the possible future increase in snow load must be considered in the planning of private and public buildings (3).

Rail transport

With regard to avalanches, the railways have a land register of the relevant avalanche tracks. Already today, critical areas are secured with protective galleries or are closely monitored during heavy snowfall. The safeguarding of further avalanche tracks could be realised relatively straightforwardly in the event that such a need arises (3).

The SBB aims at a defined forest profile along all forested route sections. In the vicinity of the tracks, small bushes and scrubs are preferred, and with increasing distance more highly growing trees, so that a clear profile is generated. Thus, falling trees can rarely cause damage anymore (3).

Construction methods can be adapted with some extra costs, so that the tracks withstand higher temperatures without damage (3).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Switzerland.

1. Federal Office for the Environment FOEN (Ed.) (2009)
2. Müller et al. (2003), in: Federal Office for the Environment FOEN (Ed.) (2009)
3. OcCC/ProClim- (2007)
4. Auld (2008b); Larsen et al. (2008); Stewart et al. (2011), all in: IPCC (2012)
5. Coleman (2002); Munich Re (2005); Auld (2008b); Larsen et al. (2008); Kwadijk et al. (2010); Mastrandrea et al. (2010), all in: IPCC (2012)
6. Ruth and Coelho (2007); Haasnoot et al. (2009), both in: IPCC (2012)
7. Schmucki et al. (2017)