Time filter

Source Type

Dobler C.,University of Innsbruck | Dobler C.,Alpnter for Climate Change Adaptation Technologies | Burger G.,University of Victoria | Burger G.,University of Potsdam | And 2 more authors.
Natural Hazards and Earth System Science | Year: 2013

The objectives of the present investigation are (i) to study the effects of climate change on precipitation extremes and (ii) to assess the uncertainty in the climate projections. The investigation is performed on the Lech catchment, located in the Northern Limestone Alps. In order to estimate the uncertainty in the climate projections, two statistical downscaling models as well as a number of global and regional climate models were considered. The downscaling models applied are the Expanded Downscaling (XDS) technique and the Long Ashton Research Station Weather Generator (LARS-WG). The XDS model, which is driven by analyzed or simulated large-scale synoptic fields, has been calibrated using ECMWF-interim reanalysis data and local station data. LARS-WG is controlled through stochastic parameters representing local precipitation variability, which are calibrated from station data only. Changes in precipitation mean and variability as simulated by climate models were then used to perturb the parameters of LARS-WG in order to generate climate change scenarios. In our study we use climate simulations based on the A1B emission scenario. The results show that both downscaling models perform well in reproducing observed precipitation extremes. In general, the results demonstrate that the projections are highly variable. The choice of both the GCM and the downscaling method are found to be essential sources of uncertainty. For spring and autumn, a slight tendency toward an increase in the intensity of future precipitation extremes is obtained, as a number of simulations show statistically significant increases in the intensity of 90th and 99th percentiles of precipitation on wet days as well as the 5- and 20-yr return values. © Author(s) 2013.


Huttenlau M.,Alpnter for Climate Change Adaptation Technologies | Huttenlau M.,University of Innsbruck | Stotter J.,Alpnter for Climate Change Adaptation Technologies | Stotter J.,University of Innsbruck | Stiefelmeyer H.,Federal Water Engineering Administration
Natural Hazards and Earth System Science | Year: 2010

Within the last decades serious flooding events occurred in many parts of Europe and especially in 2005 the Austrian Federal Province of Tyrol was serious affected. These events in general and particularly the 2005 event have sensitised decision makers and the public. Beside discussions pertaining to protection goals and lessons learnt, the issue concerning potential consequences of extreme and severe flooding events has been raised. Additionally to the general interest of the public, decision makers of the insurance industry, public authorities, and responsible politicians are especially confronted with the question of possible consequences of extreme events. Answers thereof are necessary for the implementation of preventive appropriate risk management strategies. Thereby, property and liability losses reflect a large proportion of the direct tangible losses. These are of great interest for the insurance sector and can be understood as main indicators to interpret the severity of potential events. The natural scientific-technical risk analysis concept provides a predefined and structured framework to analyse the quantities of affected elements at risk, their corresponding damage potentials, and the potential losses. Generally, this risk concept framework follows the process steps hazard analysis, exposition analysis, and consequence analysis. Additionally to the conventional hazard analysis, the potential amount of endangered elements and their corresponding damage potentials were analysed and, thereupon, concrete losses were estimated. These took the specific vulnerability of the various individual elements at risk into consideration. The present flood risk analysis estimates firstly the general exposures of the risk indicators in the study area and secondly analyses the specific exposures and consequences of five extreme event scenarios. In order to precisely identify, localize, and characterize the relevant risk indicators of buildings, dwellings and inventory, vehicles, and individuals, a detailed geodatabase of the existing stock of elements and values was established on a single object level. Therefore, the localized and functional differentiated stock of elements was assessed monetarily on the basis of derived representative mean insurance values. Thus, well known difference factors between the analysis of the stock of elements and values on local and on regional scale could be reduced considerably. The spatial join of the results of the hazard analysis with the stock of elements and values enables the identification and quantification of the elements at risk and their corresponding damage potential. Thereupon, Extreme Scenario Losses (ESL) were analysed under consideration of different vulnerability approaches which describe the individual element's specific susceptibility. This results in scenario-specific ranges of ESL rather than in single values. The exposure analysis of the general endangerment in Tyrol identifies (i) 105 330 individuals, (ii) 20 272 buildings and 50 157 dwellings with a corresponding damage potential of approx. EUR 20 bn. and (iii) 62 494 vehicles with a corresponding damage potential of EUR 1 bn. Depending on the individual extreme event scenarios, the ESL solely to buildings and inventory vary between EUR 0.9ĝ€"1.3 bn. for the scenario with the least ESL and EUR 2.2ĝ€"2.5 bn. for the most serious scenarios. The correlation of the private property losses to buildings and inventory with further direct tangible loss categories on the basis of investigation after the event in 2005, results in potential direct tangible ESL of up to EUR 7.6 bn. Apart from the specific study results a general finding shows that beside the further development of modelling capabilities and scenario concepts, the key to considerably decrease uncertainties of integral flood risk analyses is the development and implementation of more precise methods. These are to determine the stock of elements and values and to evaluate the vulnerability or susceptibility of affected structures to certain flood characteristics more differentiated. © Author(s) 2010.


Jochem A.,alpnter for Climate Change Adaptation Technologies | Jochem A.,University of Innsbruck | Hofle B.,University of Heidelberg | Rutzinger M.,University of Innsbruck | Rutzinger M.,University of Twente
Remote Sensing | Year: 2011

In recent years there has been an increasing demand among home owners for cost effective sustainable energy production such as solar energy to provide heating and electricity. A lot of research has focused on the assessment of the incoming solar radiation on roof planes acquired by, e.g., Airborne Laser Scanning (ALS). However, solar panels can also be mounted on building facades in order to increase renewable energy supply. Due to limited reflections of points from vertical walls, ALS data is not suitable to perform solar potential assessment of vertical building facades. This paper focuses on a new method for automatic solar radiation modeling of facades acquired by Mobile Laser Scanning (MLS) and uses the full 3D information of the point cloud for both the extraction of vertical walls covered by the survey and solar potential analysis. Furthermore, a new method is introduced determining the interior and exterior face, respectively, of each detected wall in order to calculate its slope and aspect angles that are of crucial importance for solar potential assessment. Shadowing effects of nearby objects are considered by computing the 3D horizon of each point of a facade segment within the 3D point cloud. © 2011 by the authors.


Jochem A.,Alpnter for Climate Change Adaptation Technologies | Jochem A.,University of Innsbruck | Hollaus M.,Vienna University of Technology | Rutzinger M.,University of Innsbruck | And 2 more authors.
Sensors | Year: 2011

In this study, a semi-empirical model that was originally developed for stem volume estimation is used for aboveground biomass (AGB) estimation of a spruce dominated alpine forest. The reference AGB of the available sample plots is calculated from forest inventory data by means of biomass expansion factors. Furthermore, the semi-empirical model is extended by three different canopy transparency parameters derived from airborne LiDAR data. These parameters have not been considered for stem volume estimation until now and are introduced in order to investigate the behavior of the model concerning AGB estimation. The developed additional input parameters are based on the assumption that transparency of vegetation can bemeasured by determining the penetration of the laser beams through the canopy. These parameters are calculated for every single point within the 3D point cloud in order to consider the varying properties of the vegetation in an appropriate way. Exploratory Data Analysis (EDA) is performed to evaluate the influence of the additional LiDAR derived canopy transparency parameters for AGB estimation. The study is carried out in a 560 km2 alpine area in Austria, where reference forest inventory data and LiDAR data are available. The investigations show that the introduction of the canopy transparency parameters does not change the results significantly according to R2 (R2 = 0.70 to R2 = 0.71) in comparison to the results derived from, the semi-empirical model, which was originally developed for stem volume estimation. 2010 by the authors.


Huttenlau M.,alpnter for Climate Change Adaptation Technologies | Huttenlau M.,University of Innsbruck | Stotter J.,University of Innsbruck
Natural Hazards | Year: 2011

In the context of natural hazard-related risk analyses, different concepts and comprehensions of the term risk exist. These differences are mostly subjected to the perceptions and historical backgrounds of the different scientific disciplines and results in a multitude of methodological concepts to analyse risk. The target-oriented selection and application of these concepts depend on the specific research object which is generally closely connected to the stakeholders' interests. An obvious characteristic of the different conceptualizations is the immanent various comprehensions of vulnerability. As risk analyses from a natural scientific-technical background aim at estimating potential expositions and consequences of natural hazard events, the results can provide an appropriate decision basis for risk management strategies. Thereby, beside the preferably addressed gravitative and hydrological hazards, seismo-tectonical and especially meteorological hazard processes have been rarely considered within multi-risk analyses in an Alpine context. Hence, their comparative grading in an overall context of natural hazard risks is not quantitatively possible. The present paper focuses on both (1) the different concepts of the natural hazard risk and especially their specific expressions in the context of vulnerability and (2) the exemplary application of the natural scientific-technical risk concepts to analyse potential extreme storm losses in the Austrian Province of Tyrol. Following the corresponding general risk concept, the case study first defines the hazard potential, second estimates the exposures and damage potentials on the basis of an existing database of the stock of elements and values, and third analyses the so-called Extreme Scenario Losses (ESL) considering the structural vulnerability of the potentially affected elements at risk. Thereby, it can be shown that extreme storm events can induce losses solely to buildings and inventory in the range of EUR 100-150 million in Tyrol. However, in an overall context of potential extreme natural hazard events, the storm risk can be classified with a moderate risk potential in this province. © 2011 Springer Science+Business Media B.V.


Achleitner S.,University of Innsbruck | Schober J.,Alpnter for Climate Change Adaptation Technologies | Schober J.,University of Innsbruck | Rinderer M.,University of Zürich | And 4 more authors.
Journal of Hydrology | Year: 2012

During recent years a hybrid model has been set up for the operational forecasting of flood discharges in the 6750km 2 Tyrolean part of the River Inn catchment in Austria. The catchment can be characterized as a typical alpine area with large variations in altitude. The paper is focused on the error analysis of discharge forecasts of four main tributary catchments simulated with hydrological water balance models. The selected catchments cover an area of 2230km 2, where the non-glaciated and glaciated parts are modeled using the semi-distributed HQsim and the distributed model SES, respectively.The forecast errors are evaluated as a function of forecast lead time and forecasted discharge magnitude using 14 events from 2007 to 2010. The observed and forecasted precipitation inputs were obtained under operational conditions. The mean relative bias of the forecasted discharges revealed to be constant with regard to the forecast lead time, varying between 0.2 and 0.25 for the different catchments. The errors as a function of the forecasted discharge magnitude showed large errors at lower values of the forecast hydrographs, where errors decreased significantly at larger discharges being relevant in flood forecasting. © 2011 Elsevier B.V.


Jochem A.,University of Innsbruck | Jochem A.,Alpnter for Climate Change Adaptation Technologies | Hofle B.,University of Heidelberg | Wichmann V.,Alpnter for Climate Change Adaptation Technologies | And 3 more authors.
Computers, Environment and Urban Systems | Year: 2012

Most algorithms performing segmentation of 3D point cloud data acquired by, e.g. Airborne Laser Scanning (ALS) systems are not suitable for large study areas because the huge amount of point cloud data cannot be processed in the computer's main memory. In this study a new workflow for seamless automated roof plane detection from ALS data is presented and applied to a large study area. The design of the workflow allows area-wide segmentation of roof planes on common computer hardware but leaves the option open to be combined with distributed computing (e.g. cluster and grid environments). The workflow that is fully implemented in a Geographical Information System (GIS) uses the geometrical information of the 3D point cloud and involves four major steps: (i) The whole dataset is divided into several overlapping subareas, i.e. tiles. (ii) A raster based candidate region detection algorithm is performed for each tile that identifies potential areas containing buildings. (iii) The resulting building candidate regions of all tiles are merged and those areas overlapping one another from adjacent tiles are united to a single building area. (iv) Finally, three dimensional roof planes are extracted from the building candidate regions and each region is treated separately. The presented workflow reduces the data volume of the point cloud that has to be analyzed significantly and leads to the main advantage that seamless area-wide point cloud based segmentation can be performed without requiring a computationally intensive algorithm detecting and combining segments being part of several subareas (i.e. processing tiles). A reduction of 85% of the input data volume for point cloud segmentation in the presented study area could be achieved, which directly decreases computation time. © 2011 Elsevier Ltd.


De Paoli F.,University of Natural Resources and Life Sciences, Vienna | Bauer A.,University of Natural Resources and Life Sciences, Vienna | Bauer A.,Alpnter for Climate Change Adaptation Technologies | Leonhartsberger C.,University of Natural Resources and Life Sciences, Vienna | And 2 more authors.
Bioresource Technology | Year: 2011

The aims of this work were to determine the specific biogas yields of steam-exploded sugarcane straw and bagasse as well as to estimate their energy potential under Brazilian conditions. Steam-explosion was carried out under different time and temperature conditions. The specific biogas yields were analyzed in batch-tests according to VDI 4630.Results have shown that steam-explosion pre-treatment increased the specific biogas yields of straw and bagasse significantly compared to the untreated material. The utilization of these by-products can contribute to 5% of the total energy consumption and thereby higher energy independence in Brazil. Further efforts in defining the optimum pretreatment conditions with steam-explosion as well as implementing this technology in large scale plants should be made. © 2011 Elsevier Ltd.


Regional management of regional contexts such as Protected Areas demands the continuous involvement of local stakeholders and citizens. These groups are not only consumers, but also co-constructors of their cultural landscapes. To ensure their persistent support, however, regional management has to take into account instruments likely to guarantee this long-term public support. This is where social capital comes into play and contributes to voluntary engagement on a long-term basis. Though not always having intended to use its knowledge on social capital, the case of the Großes Walsertal Biosphere Reserve appears to have done a good job in bringing about this long-term public support while turning it into significant degrees of innovation and economic success.


Otto J.-C.,University of Salzburg | Keuschnig M.,University of Salzburg | Keuschnig M.,Alpnter for Climate Change Adaptation Technologies | Gotz J.,University of Salzburg | And 2 more authors.
Geografiska Annaler, Series A: Physical Geography | Year: 2012

Permafrost distribution in mid-latitude mountains is strongly controlled by solar radiation, snow cover and surface characteristics like debris cover. With decreasing elevation these factors have to counterbalance local positive air temperatures in order to enable permafrost conditions. We combine high resolution surface data derived from terrestrial laser scanning with geophysical information on the underground conditions using ground penetrating radar and electrical resistivity tomography and ground surface temperature data in order to understand the effects of surface characteristics on permafrost distribution in an Alpine catchment, Austrian Alps (Glatzbach, 47°2′23.49″N; 12°42′33.24″E, 2700-2900m a.s.l.). Ground ice and permafrost is found above an elevation of 2780m a.s.l. on north-east facing slopes in 2009, previous studies detected permafrost at the same site at 2740m a.s.l. in 1991. Analysis of surface roughness as a proxy for grain size distribution reveals that the lower boundary of discontinuous and sporadic permafrost is lowered on rough surfaces compared to fine-grain zones. At the same location modelled potential summer solar radiation in coarse grain zones is reduced by up to 40% compared to surfaces of fine grain sizes. The mostly patchy permafrost distribution at the Glatzbach can therefore be attributed to local surface cover characteristics, particularly regolith grain size and its influence on solar radiation. We conclude that the analysis of ground surface characteristics using very high resolution terrain data supports the assessment of permafrost in Alpine areas by identifying rough surface conditions favouring permafrost occurrence. © 2012 The authors. Geografiska Annaler: Series A, Physical Geography © 2012 Swedish Society for Anthropology and Geography.

Loading Alpnter for Climate Change Adaptation Technologies collaborators
Loading Alpnter for Climate Change Adaptation Technologies collaborators