1 - Technische Universität München, Lehrstuhl für Ingenieurgeologie
1 - Technische Universität München, Lehrstuhl für Ingenieurgeologie
1 - Technische Universität München, Lehrstuhl für Ingenieurgeologie
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Metropolises<br />
and “their” Alps
Metropolises<br />
and “their” Alps<br />
<strong>München</strong> 2010
ForumAlpinum 2010<br />
6–9 October 2010, Munich<br />
Metropolises and “their” Alps<br />
Organisation:<br />
Gefördert durch:<br />
L E B E N S M I N I S T E R I U M<br />
B A Y<br />
E R N . D E<br />
sowie die<br />
Stiftung zur Förderung der Wissenschaften in Bayern<br />
© Bayerische Akademie der Wissenschaften, <strong>München</strong> 2010<br />
Bezugsadresse:<br />
Verlag der Bayerischen Akademie der Wissenschaften<br />
Alfons-Goppel-Str. 11, 80539 <strong>München</strong>, info@badw.de, www.badw.de<br />
Koordination und Gesamtredaktion: Dr. Ellen Latzin, Eva Samuel-Eckerle<br />
Redaktion, Layout, Satz und Umschlagentwurf: Elisabeth Lukas-Götz M.A., Thomas Böck, <strong>München</strong><br />
Titelfoto: Dr. Markus Weber, <strong>München</strong><br />
Druck und Bindung: Druckhaus Köthen GmbH, Friedrichstraße 11/12, 06366 Köthen<br />
Gedruckt auf säurefreiem, alterungsbeständigen Papier<br />
Das Werk einschließlich aller Abbildungen ist urheberrechtlich geschützt.<br />
Alle Rechte liegen bei der Bayerischen Akademie der Wissenschaften.<br />
ISCAR<br />
International Scientific Committee<br />
on Research in the Alps<br />
Schwarztorstrasse 9, CH-3007 Bern<br />
Online-Publikation im Verlag der Österreichischen Akademie der Wissenschaften<br />
http://epub.oeaw.ac.at/<br />
doi:10.1553/forumalpinum2010<br />
ISBN-Online: 978-3-7001-6866-9
Plenary Session 4<br />
Seismic Modelling Using High Performance<br />
Computing for Ground Motion Prediction in<br />
Alpine Terrain (Martin Käser, Verena Hermann,<br />
Christian Pelties)<br />
Ground motion prediction plays an important role<br />
in the estimation of seismic hazard. However, the<br />
accurate and reliable prediction of possible peak<br />
ground accelerations or velocities requires a detailed<br />
knowledge of the subsurface and thus the<br />
full complexity of a geological model must be<br />
considered in ground motion simulations. In particular,<br />
Alpine regions can be strongly affected by<br />
local site effects due to the accumulation of soft<br />
sediments in the valley floors. Additionally, topographic<br />
features of a rough relief can cause amplifications<br />
as well as reductions of the amplitude<br />
of ground motion amplitudes. Topography therefore<br />
is a critical issue in the model building process<br />
for numerical calculations of seismic wave<br />
phenomena in mountainous regions. We will give<br />
an overview of recent developments of the Discontinuous<br />
Galerkin (DG) Finite Element method<br />
and focus on its advantages for seismic modeling<br />
especially in Alpine terrain. We also will show the<br />
entire workflow for highly-accurate seismic simulations<br />
and highlight some of our latest results<br />
Mountain regions are particularly sensitive to climate<br />
change. Changes in glaciers, snow and permafrost<br />
and corresponding impacts on natural<br />
hazards in high-mountain systems could, in fact,<br />
be among the most direct visible signals of global<br />
warming and may seriously threaten human lives<br />
and infrastructures in high mountain regions. Although<br />
great advances in the recognition, prediction<br />
and mitigation of landslides have been made<br />
in the last few years, major events especially in alpine<br />
regions still claim a high social and economical<br />
tribute. Through extreme weather conditions,<br />
as e.g. the intense rainfall in August 2005, instable<br />
slopes can be activated and endanger people, settlements<br />
and goods in their surrounding. Recent<br />
landslides in the Alpine region demonstrate the<br />
need for a better understanding of the geological<br />
and physical processes, which lead to a spontaneous<br />
failure of a natural slope. Major rock-slides,<br />
such as Vajont (1963, Italy) or Randa (1991, Switzer-<br />
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obtained by applying the DG method on modern<br />
High Performance Computing infrastructure. �umerical<br />
case studies with respect to the effects of<br />
topography and soft sedimentary basins in the<br />
Grenoble region and at Mt. Hochstaufen in southeastern<br />
�avaria will be presented and compared<br />
to observational data to confirm the performance<br />
of our approach.<br />
References<br />
Chaljub, E., P. Moczo, S. Tsunoet al. (2010): Quantitative<br />
Comparison of Four �umerical Predictions of 3D Ground<br />
Motion in the Grenoble Valley, France. �ulletin of the Seismological<br />
Society of America 100,4 (in press).<br />
Igel, H., M. Käser & M. Stupazzini (2009): Simulation of<br />
Seismic Wave Propagation in Media with Complex Geometries.<br />
In: Encyclopedia of Complexity and System Science,<br />
edited by W.H.K. Lee, Springer Verlag.<br />
Käser, M., M. Dumbser & J. de la Puente (2006): An Efficient<br />
ADER-DG Method for 3D Seismic Wave Propagation in<br />
Media with Complex Geometry. In: ESG 2006, Third International<br />
Symposium on the Effects of Surface Geology on<br />
Seismic Motion 1: 455–464, Laboratoire Central des Ponts et<br />
Chaussées.<br />
Käser, M., J. de la Puente, C. Castro et al. (2008): Seismic<br />
Wave Field Modelling Using High Performance Computing.<br />
In: SEG Expanded Abstracts 27: 2884–2888.<br />
4/2 Landslides, Permafrost and Glaciers ―<br />
Increasing Mass Movement as a Sign of Global Warming<br />
Presentation: Ludwig �raun, Christoph Mayer<br />
Input: Michael Eineder, Christine Rothenbühler, Kurosch Thuro<br />
land), and recent minor events, such as Sibratsgfäll<br />
(1999, Austria), prove the destructive potential of<br />
these mass movements and highlight the need<br />
for a thorough investigation of the mechanics of<br />
these processes. Glacier and permafrost hazards<br />
in alpine regions include: outburst of glacier lakes,<br />
ice-avalanches, as well as destabilization of debris<br />
slopes and rock walls. The assessment of glacier<br />
and permafrost hazards requires systematic and<br />
integrative approaches. Presently, the most successful<br />
strategy is based on the combination of remote<br />
sensing, numerical modeling and local geophysical<br />
field surveys.<br />
The workshop will address glacier and permafrost<br />
hazards and deals with various aspects of detecting,<br />
monitoring and mitigation of slope movement<br />
at different time scales. While mitigation is<br />
the overall goal, the focus of this workshop lies in<br />
the presentation of new techniques for the detection<br />
and monitoring of small to large scale mass
movements. This includes new remote sensing<br />
techniques, as well as up-to-date developments in<br />
precise ground based point measurements.<br />
Remote Sensing of Mountain Regions with Space-<br />
Borne Radar (Michael Eineder)<br />
Since the year 1991 imaging radar systems are continuously<br />
operated on satellites for monitoring the<br />
earth. They work reliably day and night and even<br />
under cloudy or rainy conditions. The resolution<br />
of the established radar systems (e.g. ERS-1/2, E�-<br />
VISAT/ASAR) is on the order of 25 meters, which is<br />
well suited for global applications, but of limited<br />
use when it comes to regional monitoring, for example<br />
of alpine valleys.<br />
In the year 2007 Germany launched TerraSAR-X,<br />
the first instance of a new generation of SAR satellites<br />
for high resolution monitoring and mapping.<br />
The image raster of 1–3 meters, the X-band wavelength<br />
and the revisit cycle of 11 days are now much<br />
better suited to regional applications. The TerraSAR-X<br />
mission is carried out under what is known as a public-private<br />
partnership between the German Federal<br />
Ministry of Education and Research (�undesministerium<br />
<strong>für</strong> �ildung und Forschung; �M�F), the German<br />
Aerospace Center (DLR) and Astrium GmbH, DLR.<br />
The operation of TerraSAR-X is a success story since<br />
its launch and a great number of application exam-<br />
Georisks and Geo-Resources | Workshops<br />
ples have been demonstrated since. Application<br />
areas with high relevance for alpine regions are:<br />
– measurement of mountain topography and its<br />
changes<br />
– measurement of glacier extent and glacier motion<br />
vector field<br />
– measurement of tectonic changes<br />
– detection of larger landslides<br />
– measurement of creeping landslides with millimetric<br />
accuracy<br />
– structural monitoring of larger infrastructure<br />
such as bridges, dams and buildings<br />
Focusing on the above topics, the talk summarizes<br />
what satellite radar can accomplish today and<br />
outlines what could be done specifically for alpine<br />
regions in the future.<br />
References<br />
Adam, �., A. Parizzi, M. Eineder et al. (2009): Practical Persistent<br />
Scatterer Processing Validation in the Course of the Terrafirma<br />
Project. Journal of Applied Geophysics 69/1: 59–65. –65. 65.<br />
�amler, R., M. Eineder, �. Adam et al. (2009): Interferometric<br />
Potential of High Resolution Spaceborne SAR. Photogrammetrie<br />
Fernerkundung Geoinformation 5: 403–415. –415. 415. E.<br />
Schweizerbart‘sche Verlagsbuchhandlung, Stuttgart.<br />
doi: 10.1127/1432-8364/2009/0029.<br />
Eineder, M., �. Adam, R. �amler et al. (2009): Spaceborne<br />
Spotlight SAR Interferometry with TerraSAR-X. IEEE Transactions<br />
on Geoscience and Remote Sensing 47 (Issue 5):<br />
1524–1535. –1535. 1535.<br />
Fig. 1: With the double formation TerraSAR-X / TanDEM-X it will be possible to survey the whole surface<br />
of the earth (150 mill. km²) within 2.5 years (Source: EADS Astrium).<br />
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Plenary Session 4<br />
Rabus, �., M. Eineder, A. Roth et al. (2003): The Shuttle Radar<br />
Topography Mission (SRTM) – A �ew Class of Digital Elevation<br />
Models Acquired by Spaceborne Radar. ISPRS Journal<br />
of Photogrammetry & Remote Sensing 57/4: 241–262. –262. 262.<br />
doi: 10.1016/S0924-2716(02)00124-7.<br />
Hazards Related to Permafrost Degradation:<br />
the Example of Pontresina (Engadine Valley,<br />
Switzerland) (Christine Rothenbühler)<br />
Many features in the high mountain environment<br />
such as glaciers, permafrost, vegetation or soil<br />
are very climate-sensitive and could experience<br />
large changes in the future. As a consequence,<br />
the potential starting zones for natural hazards,<br />
the dynamics of processes, the areas potentially<br />
affected by natural hazards and the attractiveness<br />
of the landscape are likely to change as well.<br />
Therefore, the high mountains can be seen as a<br />
complex system in which various features react<br />
to the rising temperatures in different time scales<br />
and intensities. The geoinformation system “GIS-<br />
ALP” was developed to assess future changes in<br />
the Upper Engadine Valley. Several models, socalled<br />
modules, simulate the present and future<br />
distribution of landscape features and processes.<br />
The results of the modules can be visualised over<br />
a satellite image or in 3D, with the help of a digital<br />
elevation model. GISALP makes it possible for<br />
the first time to model not only one specific landscape<br />
feature or natural hazard process by itself,<br />
Fig. 2: Avalanche and Debris Flow Protection Above Pontresina, Engadine Valley, Switzerland.<br />
Photo: L. Braun, 17.6.2006.<br />
104<br />
but it allows us to look at the landscape as a synthesis<br />
of the different processes and to visualize<br />
its reaction to rising temperatures. Considering<br />
the results of several modules, it will become possible<br />
to calculate the attractiveness of the landscape.<br />
�y comparing the results from different<br />
years of one module, areas undergoing changes<br />
can be identified. A comparison of the changing<br />
areas among themselves allows statements<br />
about the speed, spatial distribution and acceleration<br />
of the changes. The results of the natural<br />
hazard modules can be overlayed with data of<br />
current infrastructure, and areas of potential future<br />
problems can be identified. In the Upper Engadine<br />
the economy depends largely on tourism,<br />
and an area with decreasing landscape attractiveness<br />
will also become a problem area. �y analysing<br />
a chain of natural hazard events, it is possible<br />
to assess the effects of the combination of an ice<br />
avalanche, rushing into a glacier lake and thereby<br />
causing a debris flow, for example.<br />
The above-mentioned methodology can be exemplified<br />
in the case of Pontresina. The slopes immediately<br />
above this tourist centre are famous for<br />
its impressive historical and recent construction<br />
work against snow avalanches and debris flows.<br />
Extensive research was carried out starting in 1989<br />
to ensure the safety and well-being of the visitors<br />
and residents of Pontresina. So far, Pontresina has<br />
been spared from major natural catastrophes,<br />
largely on account of far-sighted investments in<br />
avalanche and landslide defence systems. Pont-
esina began early on to address the possible effects<br />
of climate change, and today, as a pioneer in<br />
avalanche and landslide defence systems, boasts<br />
a range of comprehensive protection measures.<br />
Measurements in a more than 20 m deep rock<br />
glacier on Schafberg mountain above Pontresina<br />
show that its temperature is approximately at<br />
the melting point. The rock glacier is expected to<br />
thaw slowly over the coming years and decades,<br />
posing a new threat of landslides in the avalanche<br />
starting zone. The constructed dams, which blend<br />
in very well with the surrounding landscape, dispense<br />
the need to build approximately 10 km of<br />
avalanche defence, whilst protecting from new<br />
landslide and avalanche threats. The example of<br />
Pontresina shows how scientific investigations<br />
can help the communal government to protect<br />
the public from natural hazards related to global<br />
warming.<br />
References<br />
Kneisel, C., C. Rothenbühler, F. Keller et al. (2007): Hazard<br />
Assessment of Potential Periglacial Debris Flows �ased on<br />
GIS-based Spatial Modelling and Geophysical Field Surveys:<br />
A Case Study in the Swiss Alps. Permafrost and Periglacial<br />
Processes 18: 259–268. –268. 268.<br />
Meilwes, J., W. Haeberli, F. Keller et al. (2004): A Socio-economic<br />
and Landscape-ecological Examination of Rapidly<br />
Changing Climate-sensitive High-mountain Environments.<br />
Eco-complexity and Dynamics of the Cultural Landscape,<br />
Gießen.<br />
Rothenbühler, C. (2006): GISALP, Räumlich-zeitliche Modellierung<br />
der klimasensitiven Hochgebirgslandschaft des<br />
Oberengadins. Studien des Institutes <strong>für</strong> Tourismus und<br />
Landschaft (ITL). Academia Engiadina, Samedan.<br />
Low Cost 3D Early Warning System for Alpine<br />
Instable Slopes (Kurosch Thuro)<br />
Co-leaders of the project: Thomas Wunderlich, <strong>Technische</strong><br />
<strong>Universität</strong> <strong>München</strong>, <strong>Lehrstuhl</strong> <strong>für</strong> Geodäsie,<br />
Otto Heunecke, <strong>Universität</strong> der �undeswehr<br />
<strong>München</strong>, Institut <strong>für</strong> Geodäsie.<br />
In the context of global climate change and the<br />
continuous extension of settlement areas in Alpine<br />
regions, especially due to tourism, an increasing<br />
conflict between land use and natural hazard prevention<br />
can be observed. This also includes deepseated<br />
landslides, which, if activated, can cause<br />
considerable damage to settlements and infrastructure<br />
and can even endanger lives. To date, the<br />
hazard potential of slow deep-seated landslides is<br />
often underestimated. For economic reasons such<br />
potentially dangerous instable slopes are often<br />
only monitored sporadically. The alpEWAS project<br />
(“development and testing of an integrative 3D<br />
Georisks and Geo-Resources | Workshops<br />
early warning system for alpine instable slopes”) is<br />
currently developing a low-cost 3D monitoring and<br />
early warning system for landslides based on three<br />
cost-efficient and innovative continuous measurement<br />
systems: Time Domain Reflectometry (TDR)<br />
for the detection of subsurface movements in boreholes,<br />
the low-cost global navigation satellite system<br />
(G�SS), and reflectorless video tacheometry<br />
(TPS) for highly precise and extensive measurements<br />
of surface movements.<br />
These measuring systems and further sensors, including<br />
e.g. a weather station and piezometers, are<br />
integrated into a wireless geo sensor network based<br />
on customary and therefore cost-efficient WLA�<br />
hardware. A computer centre manages all system<br />
operations, e.g. data collection and logging and controlling<br />
of the sensor nodes. The analysis of the spatially<br />
and timely highly resolved data will enable to<br />
identify correlations between triggering events (e.g.<br />
precipitation) and the movement of the landslide.<br />
This, together with numerical analyses of the landslide,<br />
will allow the definition of threshold values<br />
for the continuously monitored triggering factors,<br />
thus establishing an early warning system. In case<br />
of a likely event, the stake holders can be notified<br />
via email or SMS, enabling them to timely induce<br />
counter measures or evacuate the affected region.<br />
In 2008 the alpEWAS geo sensor network was<br />
installed at the Aggenalm landslide (Sudelfeld, �avaria)<br />
in order to prove the functionality and reliability<br />
of all system components (Fig. 3). To date all<br />
measuring systems and the network infrastructure<br />
are operational.<br />
References<br />
Singer, J., St. Schuhbäck, P. Wasmeier et al. (2009): Monitoring<br />
the Aggenalm Landslide Using Economic Deformation<br />
Measurement Techniques. Austrian Journal of Earth Sciences<br />
102/2: 20–34. –34. 34.<br />
Singer, J., K. Thuro & U. Sambeth (2006): Development of<br />
a Continuous 3D-monitoring System for Unstable Slopes<br />
Using Time Domain Reflectometry. Felsbau 24/3: 16–23. –23. 23.<br />
Thuro, K., J. Singer, J. Festl et al. (2010): �ew Landslide Monitoring<br />
Techniques – Developments and Experiences of the<br />
alpEWAS Project. Journal of Applied Geodesy (in print).<br />
Thuro, K., Th. Wunderlich & O. Heunecke, J. Singer, St.<br />
Schuhbäck, P. Wasmeier, J. Glabsch & J. Festl (2009): Low<br />
Cost 3D Early Warning System for Alpine Instable Slopes –<br />
the Aggenalm Landslide Monitoring System. Geomechanics<br />
& Tunnelling 3: 221–237. –237. 237.<br />
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Plenary Session 4<br />
Fig. 3: Schematic Illustration of the “alpEWAS” Integrative 3D Early Warning System for Instable Slopes Currently Installed<br />
at the Aggenalm Landslide, Sudelfeld, Bavaria.<br />
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