Spain

Avalanches, Landslides and Rock fall Spain

Vulnerabilities

Most of western Europe (with the partial exception of France) suffers relatively few significant landslides. By contrast, the Mediterranean basin (e.g. southern Italy and the eastern Iberian Peninsula) and the mountain regions of central and eastern Europe are particularly vulnerable to these events. High tectonic activity and relatively recent sand and clay deposits increase these regions’ susceptibility to landslides, and this vulnerability increases if urbanisation and poor forest management are present (1).

There is an increasing frequency of landslides in Spain, and these are estimated to have caused the national economy losses amounting to some 36 million euro/year during the 1990s (2).

IPCC conclusions in 2012

In 2012 the IPCC concluded that there is high confidence that changes in heat waves, glacial retreat, and/or permafrost degradation will affect high mountain phenomena such as slope instabilities, mass movements, and glacial lake outburst floods, and medium confidence that temperature-related changes will influence bedrock stability. There is also high confidence that changes in heavy precipitation will affect landslides in some regions (4). There has been an apparent increase in large rock slides during the past two decades, and especially during the first years of the 21st century in the European Alps (5) in combination with temperature increases, glacier shrinkage, and permafrost degradation.

There is medium confidence that high-mountain debris flows will begin earlier in the year because of earlier snowmelt, and that continued mountain permafrost degradation and glacier retreat will further decrease the stability of rock slopes. There is low confidence regarding future locations and timing of large rock avalanches, as these depend on local geological conditions and other non-climatic factors (4). Research has not yet provided any clear indication of a change in the frequency of debris flows due to recent deglaciation. In the French Alps, for instance, no significant change in debris flow frequency has been observed since the 1950s in terrain above elevations of 2,200 m (6). Processes not, or not directly, driven by climate, such as sediment yield, can also be important for changes in the magnitude or frequency of alpine debris flows (7).

Adaptation strategies

The response to the expected increase in the frequency and gravity of extreme events should be to restore and set back in security major hydro-geological risk areas. Security regulations for buildings in rivers’ expansion areas and in areas at risk of landslides and avalanches need to be applied. Low vegetal cover areas need to be reforested with the aim of mitigating the climate warming effects and adapting the territory to induced risks (soil defence, desertification) (3).

An even more efficient system of meteorological early warning should be introduced in the higher risk areas for floods and landslides, in order to intervene in a preventive way where it is already known that emergencies will happen (3).

In southern Europe the risk of landslides is reduced through revegetation on scree slopes, which enhances cohesion and slope stability coupled with improved hazard mitigation (8).

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 Spain.