Search

Lake surface temperature (LST) is a key characteristic of lakes, shaping the ecological properties of these inland water bodies and their environment. This study aims at establishing a long-term, high-quality, monthly LST dataset within the European Alps reaching back to 1880, which is provided to the scientific community for further research. Therefore monthly temperature records from Austrian lakes covering a period of about six decades are digitized from hydrological yearbooks. Clustering techniques (rotated empirical orthogonal functions and hierarchical cluster analysis) are used to identify groups of lakes signified by inner similarity and outer separation. These are not only used for an overall quality assessment, but also provide optimal starting conditions for the application of a homogenization procedure, warranting homogeneous LST data from 1950 onwards. LST reconstructions back to 1880 are derived from atmospheric covariates (provided by HISTALP) via sets of transfer-functions. Applied transfer-functions have passed a selection process ensuring mathematical, physical and quality requirements. They are selected from about 160 million candidates according to skill, which is determined through a comprehensive assessment based on validation experiments and several performance measures. Results show overall high skill following a seasonal cycle. From 1880 to 1950 LSTs feature generally slight increases accompanied by a succession of climate states. These are in alignment with outstanding climate periods and sustained, far-reaching repercussions triggered by significant events, which are known from historical documents. LST developments throughout the second half of the twentieth century up to date are characterized by a decline until the mid-1980s, indicating the impact of industrial aerosols. This behaviour is superseded by a steep increase, revealing the gradual unmasking of the anthropogenic greenhouse effect by the continuous reduction of aerosol loads in the atmosphere. The latter substantiates man-made climate change, whose prove is based on atmospheric variables by different data pertaining to the hydrosphere. Potential research hypotheses corresponding to various fields of science that may be investigated by using the here established LST dataset are considered. We hope that these data sets and associated findings will make a contribution to the broader research community. [ABSTRACT FROM AUTHOR]

• Vulnerability curves may overestimate loss for some events. • Vulnerability indices complement vulnerability curves giving better insights into the interaction between a building and a physical process. • Process intensity is a key variable for the assessment of physical vulnerability. • Indices should be constantly updated using data from upcoming events and a wider indicator inventory. • Sensitivity analysis of some variables is a valuable support for improved damage and event documentation. Vulnerability analysis is crucial to assess natural hazard risk. Methods for vulnerability assessment include indices as well as vulnerability curves. Vulnerability curves make use of empirical data to show the relationship between the process intensity and the resulting degree of loss on each affected building whereas vulnerability indices are based on a number of indicators representing building characteristics and their surroundings. In the present paper, damage data from two relatively recent torrential events in the European Alps are used to compare results using a vulnerability curve (Beta model) and a physical vulnerability index (PVI). Following the application of both methods, their strengths and weaknesses are outlined. Vulnerability curves constitute a valuable quantitative method for the assessment of physical vulnerability but, in the present study, they tend to overestimate damages. On the other hand, vulnerability indices better support the understanding of local-scale damage patterns but they require detailed data and further research on weighting and indicator selection. The study leads to the conclusion that both methods complement each other providing better insights into the physical vulnerability of buildings exposed to torrential hazards. Furthermore, uncertainties associated with the two approaches are related to the required data. Therefore, a sensitivity analysis is carried out showing that process intensity is a key variable for the assessment of vulnerability, whereas, differences in the calculation of the degree of loss based on different building values are less important. Finally, the paper gives clear recommendations for improved event and damage documentation and provides an outlook on future needs in vulnerability assessment, including constant updating of both methods based on recent events. [ABSTRACT FROM AUTHOR]

Due to an administrative error the incorrect, unrevised version of this paper has appeared online initially and for some time. The original article has now been corrected. [ABSTRACT FROM AUTHOR]

Because effects of climate change and an increase in elements at risk, mountain hazard loss increased throughout Europe. Yet, factors influencing loss, i.e. vulnerability, have gained less attention to date. Vulnerability is defined as the degree of loss resulting from the hazard impact on buildings. Recent studies have focused on evaluating vulnerability to dynamic flooding using proxies from case studies and based on empirical ex-post approaches. However, the transferability to other case studies and, therefore, the ability of such models to actually predict future losses is limited. To overcome this gap, we present a beta model based on loss data from the European Alps, which clearly shows that a single vulnerability function is sufficient to predict losses resulting from different types of torrential hazards and to provide probabilities of destruction under specific scenarios. As a result, the curves are transferable and may significantly increase the predictive power of risk analyses. • We assess physical vulnerability of buildings exposed to torrential hazards. • A beta model was used to link process magnitude to the degree of loss. • The model can be used for loss prediction considering all damage stages from possible no loss to complete destruction. • The model is applicable to dynamic flooding with varying sediment concentration. [ABSTRACT FROM AUTHOR]

• Stablishing Austrias most comprehensive database of weather-triggered hazards. • Creation of an 'event space' (1950–2015) comprising more than 20000 hazards. • Objective derivation of hazard-inducing weather sequences (climate indices). • Characteristic linkage between weather sequences, process categories and regions. • Demonstration of general applicability across a wide topographical range. • Contribution to public protection through improving early warning strategies. Floodings and landslides are amongst the most devastating damage-processes worldwide. Associated risk levels are particularly high in topographically complex terrain. Along with the increase in climate-change induced extreme events, research devoted to the identification of so-called Climate Indices (CIs) describing weather phenomena triggering hazard-occurrences and -intensities gains rising emphasis. In this study we accomplish the first-time unification of the three most comprehensive cadastres on weather-induced hazard-processes, compiled and maintained by federal authorities. The therefrom resulting ‟event spaceˮ stretches seven decades from 1950 onwards and contains more than 20 000 hazard-occurrences, classified into different process-categories. Event data are analyzed together with a high-quality, daily-based dataset providing temperatures and precipitation-totals on a 1 km grid across the Austrian part of the European Alps. On the resulting unprecedented extent of extreme-weather triggered hazard-processes and gridded weather observations we are able to examine the hypothesis that daily sequences of precipitation-totals preceding damage-events allow for the detection of temporal weather-sequences uniquely allocatable to various hazard-categories in three orographically distinct regions in the European Alps. We pursue this research aim by analyzing for each hazard-category its quadratic form representing the physics contained in the observations. Resulting eigen-directions, invariant under its inherent second order tensor, are the sought-for total-sequences (CIs) and hence reject the alternative hypothesis. Therefore, precipitation total-sequences can be uniquely assigned to hazard-categories within each region. It is important to note that findings based on this novel, objective approach do not contradict, but rather add to attained research achievements by introducing this new perspective on the subject. Obtained CIs have substantial potential in research and applications. In civil defense, safeguarding critical infrastructure, early warning systems and the development of sustainable protection strategies, findings are in implementation by responsible decision-makers and in intense discussion with the European Freight and Logistics Leaders' Forum. [ABSTRACT FROM AUTHOR]

Floodings and landslides are amongst the most devastating damage-processes worldwide. Associated risk levels are particularly high in topographically complex terrain. Along with the increase in climate-change induced extreme-events, research devoted to the identification of so-called Climate Indices (CIs) describing weather phenomena triggering hazard-occurrences and intensities gain rising emphasis.In this study we accomplish the first-time unification of the three most comprehensive cadastres on weather-induced hazard-processes, compiled and maintained by federal authorities. The therefrom resulting 'event space' stretches seven decades from 1950 onwards and contains 20.000 hazard occurrences, classified into six different process-categories. Event data are analyzed together with a high-quality, daily-based dataset providing temperatures and precipitation totals on a 1 km grid across the Austrian part of the European Alps. On the resulting unprecedented extent of extreme-weather triggered hazard-processes and gridded weather observations, we are able to examine the hypothesis that daily sequences of precipitation-totals preceding damage-events allow for detecting temporal weather-sequences uniquely allocatable to various hazard-categories in three orographically distinct regions in the European Alps. We pursue this research aim by analyzing for each hazard-category its quadratic form representing the physics contained in the observations. Resulting eigen-directions, invariant under its inherent second order tensor, are the sought-for total-sequences (CIs) and hence reject the alternative hypothesis. Therefore, precipitation total-sequences can be uniquely assigned to every hazard category within each region, giving an overall of 18 CIs. It is important to note that findings based on this novel, objective approach do not contradict, but rather add to attained research achievements by introducing this new perspective on the subject. Obtained CIs have substantial potential in research and applications. In civil defense, safeguarding critical infrastructure, early warning systems and the development of sustainable protection strategies, findings are in implementation by responsible decision-makers and in intense discussion with the European Freight Leaders Forum. [ABSTRACT FROM AUTHOR]

Contents of this contribution sketch the derivation of this procedure and its successful application to the (so-far) largest and most complex civil-protection project implemented in Austria after WWII. Results, rely largely on three master theses carried out within a cooperation of the Climate Impact Team (CIT) at ZAMG, the BMNT and the Institute of Meteorology and Geophysics at the University of Vienna. Apart therefrom findings profit greatly from a close cooperation of CIT and the European Freight and Logistics Leaders' Forum (F&L). The goal is to support decision makers in designing and implementing efficient and sustainable protection against changing threats. This necessitates extensive preparatory work: (i) the generation of ensembles comprising regional-scale climate-change scenarios until 2100, driven by different pathways of mankind (RCPs: 2.6, 4.5 and 8.5, RCPs - Representative Concentration Pathways); (ii) facilitated under the umbrella of the BMNT: first-time integration of the three most comprehensive national cadasters of extreme-weather induced hazard-events; the outstanding scope and quality of these cadasters enable the compilation of the so-called 'event space', which is now Austria's most extensive database of weather driven hazard-processes (well above 20.000 records from 1948 onwards); this wealth of observations (we focus here on landslides and floodings) allows for (iii) in depth analyses (von Storch and Zwiers, 1999) of linkages between extreme weather and potential damage events, distinguishing at the same time (iv) amongst process-categories as well as sub-regions within Austria's share of the European Alps: 'Alpine Territory', 'Northern Lowlands' and the 'Southern Basin Chain'; blending (v) the 'event space' with spatial high-resolved, daily observations of precipitation totals and temperature values (SPARTACUS, Hiebl and Frei 2015, 2017) sets the frame required for the (vi) identification-procedure of region- and category-sensitive weather sequences triggering potential damage-events (so-called Climate Indices, CIs); step (vii) derives future CIs occurrences from previously downgescaled ensembles within 'near' (2036-2065) and 'remote' periods (2071-2100) and assesses results in terms of current levels; sustainable protection structures must withstand these 'near' (and 'remote') threat levels;Step (viii) finally demonstrates the successful application of the procedure calibrated by the expertise of our partners in charge of public protection protection, to Austria's (so far) largest project in public protection since WWII, in which methods currently available have not provided guidance. Presently BMNT surveys adjustments required for the integration of the procedure. Aside therefrom, its application to critical transport infrastructure is in discussion with the Forum of European Freight and Logistics Leaders (F\&L), because members are experiencing rises of supply-chain disruptions due to climate-change driven hazard events. [ABSTRACT FROM AUTHOR]