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• 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]

• Context: Among natural disturbances, wind storms cause the greatest damage to forests in Austria. • Aim: The aim of this study is to quantify the effects of site, stand and meteorological attributes on the wind disturbance regime at the operational scale of forest stands. • Methods: We used binomial generalized linear mixed models (GLMMs) to quantify the probability of damage events and linear mixed models (LMMs) to explain the damage intensity at the forest stand level in four management units with a total forest area of approximately 28,800 ha. • Results: Timber stock volume, stand age, elevation, previous disturbances, wind gust speed and frozen state of soil contributed in explaining probability of wind damage. While the model of disturbance probability correctly classified 90 % of all cases in the data set (specificity 95 %, sensitivity 26 %), the model for damage intensity explained only low percentages of the variation in the observed damage data (full model R = 0.38, fixed effects-only model R = 0.09; cross-validation in the four forest management units yielded similar R values). • Conclusion: The developed models indicated that decreasing the proportion of Norway spruce ( Picea abies [L.] Karst), limiting stand age and reducing the timber stock in course of tending treatments in stands exposed to wind disturbance can mitigate the risk and the expected damage intensity. High gust speeds and salvage cuts after earlier damage increase the probability of further wind disturbance events. [ABSTRACT FROM AUTHOR]

Highlights: [•] Modelling probability and intensity of bark beetle disturbances at stand scale. [•] Stand, site and climate data provided at large spatial scale and high resolution. [•] Temporal and spatial autocorrelation taken into account in a mixed model framework. [•] Bark beetle phenology included in the models. [•] Models can be used for risk analysis outside of the study area. [ABSTRACT FROM AUTHOR]

Key message: Autumn and spring frost events caused wide variation in the survival of juvenile Douglas-fir in Austrian forest sites located in the transition zone from Atlantic to continental climate. Survival rate can be optimized by planting provenances originating from an altitudinal belt of 500–1400 m in North America. Neither the variety nor the climate of origin of planted Douglas-fir provenances influence its response to frost events. Context: Understanding the risks of frost during late spring and early autumn is crucial for planting non-native Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco) as an alternative tree species under climate change in Europe. Aims: We investigate the role of early and late frost events on the survival of juvenile Douglas-fir and tested whether survival depends on seed origin. Methods: With data from 19 provenance trials across Austria, we modeled the effects of early and late frost events on juvenile survival rate, accounting for random variations due to site condition and provenance origin. Results: Wide variations (37–93%) in the juvenile survival rate of Douglas-fir were mainly driven by early and late frost events (daily Tmin < 0 °C), summer drought, and continentality. Juvenile survival declined with an increasing number of frost events within the observation period and prevailing warm spells preceding the frost events. The seed origin of the tested provenances had a minor effect and was related to the altitude, but not to the variety or the climate of provenance origin. Conclusion: For planting Douglas-fir in the transition zone from Atlantic to continental climates, typical in Austrian forests, the local site conditions and the probability of the occurrence of early and late frosts should be considered, while provenance selection should rather focus on productivity. [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]

Extreme events, such as heat waves and floodings, constitute major challenges for all organizations and institutions responsible for protection, support and medical assistance of civilians. Therefore the ongoing enhancement of alert and warning systems is highly desirable. In particular the investigation of climate change driven effects on extreme events will help agencies to plan their medium to long term resources. We thus investigate the relationship between large scale synoptic weather patterns and extreme events on the regional scale in Austria and thereby focus on studying how the frequency, duration and intensity of weather patterns change under global warming by performing nonstationary regression. Furthermore the impact of these trends in the large scale weather patterns on extreme precipitation and temperature events in Austria is analyzed. Achieved results shall significantly support disaster protection and relief organizations' anticipatory medium to long term planning of resources. [ABSTRACT FROM AUTHOR]