This study describes the results of two large-scale tests of dry granular flows interacting with a flexible barrier. Motions of multiple granular flows and their interaction behaviors with the flexible barrier are presented and analyzed. Impact forces on the flexible ring net directly and on the supporting structures have been measured and compared. The comparison result indicates the impact force reduced by the flexible ring net. Simple methods for impact force estimation are also verified. Hide

This study investigates the role of the clustering of extratropical cyclones in driving wintertime wind losses across a large European region. To do this over 900 years of climate model data has been used and analysed. The main conclusion of this work is that cyclone clustering acts to increase wintertime wind losses by 10–20 % when compared to the losses from a random series of cyclones, with this specifically being for the higher loss years. Hide

Coping with avalanche hazard has long tradition in alpine countries. Hazard mapping proved to be one of the most effective methods. In this paper we develop a new approach to automatically delineate avalanche release areas and connect them to state-of-the-art numerical avalanche simulations. This enables computer based hazard indication mapping over large areas such as entire countries. This is of particular interest, where hazard maps not yet exist such as in developing countries. Hide

The aim of this study is to investigate the differences in the mappable characteristics of earthquake-triggered and rainfall triggered landslides in terms of their frequency-area relationships, spatial distributions and relation with causal factors, and to evaluate whether separate susceptibility maps generated for specific landslide size and triggering mechanism are better than a generic landslide susceptibility assessment including all landslide sizes and triggers. Hide

We present a comprehensive sensitivity analysis considering changes along the complete flood risk chain to understand how changes in different drivers affect flood risk. Results show that changes in dike systems or in vulnerability may outweigh changes in often investigated components, such as climate change. Although the specific results are conditional on the case study and assumptions, they highlight the need for a broader consideration of potential drivers of change in a comprehensive way. Hide

we investigate the energy dissipation capacity of a single ring under different amount of tensile loading. A numerical model of the ring net for application in modelling flexible barriers is then presented.We find the release of boundary conditions can increase the overall flexibility of the ring net. As the impact angle increases, the impact energy of the rock will experience a gradual decline. The derived energy dissipation formulas provide a theoretical basis for engineering barriers. Hide

In this research drought risk in Turkey were analyzed by using drought hazard and vulnerability indexes. The methodology is developed in the first time for calculating aforementioned indexes. Results illustrate that, not only climatic variables but also social characteristic of region are essential for drought risk assessment. Results also shows that If drought hazard index is lower and drought vulnerability index is high, drought risk may higher. Hide

Very large wildfires have high human, economic and ecological impacts. Preventing such events is a major objective of the new fire policy set up in France in 1994, which is oriented towards fast and massive fire suppression. This study investigates the effect of this policy on the largest fires. We estimate the burnt area corresponding to fires that occur every 5, 20 and 50 years in average (so-called return periods) in southern France. Hide

This paper proposes an innovative method for optimizing the transmissions of high throughput satellites based on weather forecasts. Such transmissions are particularly sensitives to the presence of hydrometeors which attenuates the signal. A model to forecast the attenuation based on forecasted rainfall amounts is presented. The valuable contribution of weather forecasts in the system optimization is demonstrated as well as the benefit of using ensemble forecast over deterministics forecasts. Hide

We present an analysis of wave recordings along the south and south-west coasts of the United Kingdom, during the winter of 2013–2014. The storm that led to the collapse of the seawall at Dawlish is analysed in detail. The distribution of energy with wave period revealed a bimodal shape, with peaks in energy at approximately 7secs and 14secs. In many instances conditions lay outside the limits of empirical design formulae, providing an explanation for the extensive damage that occurred. Hide

This manuscript presents the comparison of two numerical models, which model tsunami inundation that incorporates the built environment of coastal communities. It was found that the 2D model did not accurately capture the important details of the flow near initial impact due to the transiency and large vertical variation of the flow. The 3D model was able to capture transient characteristic of the flow, but at a much higher computational cost. Hide

We adopted the projected rainfall coupled with simulations including landslide, debris flow, and loss assessment to investigate the impact on sediment-related disaster. The Xindian watershed upstream from Taipei was identified and two extreme rainfall from the late 20th and 21st centuries were selected. The economic losses are projected to increase by 27.8 % due to the increasing disasters caused by climate change. The influence on downstream city will be mainly in the form of indirect impact. Hide

The objective of this paper is to present a new methodology for the analysis of the seismic induced tsunami hazard. The proposed methodology mainly relies on uncertainty quantification techniques and the construction and validation of some emulators, or meta-models, used instead of the original models for the construction of a numerical tsunamis database. The methodology was tested with tsunamis generated by the Azores-Gibraltar Fracture Zone and potentially impacting the French Coast. Hide

Multi-satellite/sensor observations and ground-based measurements combined with the HYSPLIT model were used to analyse the dynamical processes of the origin and transport of the strong dust storm. The optical and microphysical properties of the dust particles were analysed using AERONET measurements. The combined observations revealed comprehensive information about the dynamic transport of dust and the dust affected regions, and the effect of dust storms on the aerosol properties. Hide

This paper proposes a new method that integrated the Analytic Hierarchy Process (AHP) and the Difference Method (MD) to assess susceptibility of geological hazards within MapGIS environment. The major principle of this method is that predict the probability of occurring geological hazards based on occurrence mechanism of occurred geological hazards and the geological conditions that caused geological hazards. Most of areas of the study area are under the moderate and low susceptibility zones. Hide

A catastrophic flood south of the Alps in 1868 is assessed using documentaries, a reanalysis, and the earliest high-resolution weather simulation so far. Simulated weather dynamics agree well with observations and damage reports, while simulated peak water levels are biased. No flood-causing effect by low forest cover is found, but such a paradigm was used to implement afforestation. The simulations – supported by historical methods – have potential to shed new light on long past weather events. Hide

An early warning system with a risk-based approach for drought assessment in the Bolivian Altiplano was established using satellite imagery data focusing on ENSO phases. During warm ENSO phase resulted a great difference in risk and crop yield. ENSO early warning forecasts and possible crop deficits could be established, including the identification of hotspots for the growing season. Our approach could lead a proactive approach for drought management that can include risk reduction instruments. Hide

In this paper the investigation of the main climatic mudflow conditions in Uzbekistan based on local observational data and peer-reviewed material from non-English literature which is widely missing in scientific, peer-reviewed international literature making it accessible for an international research community for the first time. Hide

Climate change is susceptible to affect the safety of water infrastructures such as dams. However, related information is vast and scattered, and the assessment of these impacts remains complex. This article seeks a multidisciplinary review of the potential impacts of climate change in every component of dam safety. This will provide useful information for dam owners and dam safety practitioners in their decision-making process. Hide

Anticipating the flight path of a bouncing object wields fascination over playing children and scientists alike. While the path of a ball can be judged easily, the erratic rebound behaviour of complex shaped forms are intriguing. Here, we focus on the time scales and rotation changes during real rock-ground impacts while travelling down a slope. Specialized sensors inside the rock track those changes and reveal contact times in the millisecond range defining the overall flightpath behaviour. Hide

This paper reviews the computation of Coastal Vulnerability Indexes (CVI) of a coast towards inundation, due to a known model. We refer to the original proposal, detailing in a second moment the CVI computation through an accurate investigation of the local wave climate. We prove that the resulting vulnerability is very sensitive due to the wave features taken into account, which have to be properly assessed. The research is the follow-up of a wider project set along the bay of lalzit (Albania). Hide

In Merapi volcano, lava dome failure may generate pyroclastic flow and threaten populations who living on its flanks. Here, I assessed the potential hazard of the Merapi lava dome by using drone photogammetry and numerical modeling. Results show a weak structural depression that associated with high thermal at the southern Merapi lava dome sector. The southern lava dome sector may further destabilize by a typical rainfall at Merapi summit and produce pyroclastic flow up to 4 kilometers distance. Hide

The source model was considered as a stochastic submarine earthquake. As the noise intensity increases, the amplitude and oscillation of the tsunami wave increases. The amount of water displaced increases as the length of the source model increases. The potential energy increases as the height of the wave increases. The L² norm can be useful when there are no adequate data about the bottom topography. The average velocity may provide warning of a tsunami approach, based on velocity oscillations. Hide

Two forecasting chains are forced by information from numerical weather predictions. The framework presented in the companion paper by Antonetti et al. has been set up for the Swiss Verzasca basin. The forecasts obtained with the uncalibrated RGM-PRO model are compared to forecasts yielded by the calibrated PREVAH-HRU model. Results shows that the uncalibrated model is able to compete with the calibrated operational prediction system and was consistently superior for high-flow situations. Hide

To predict timing and magnitude peak runoff meteorological and calibrated hydrological models are commonly coupled. A flash floods forecasting chain is presented based on a process-based runoff generation module with no need for calibration. This chain has been evaluated using data for the Emme catchment (Switzerland). The outcomes of this study show that operational FF predictions in ungauged basins can benefit from the use of information on runoff processes. This paper has a companion paper. Hide

Certain general rules about the effect of impact angle on coefficients of restitution in rockfall simulation hold regardless of the laboratory test scales and conditions. Increasing impact angle will induce reductions in R_n and R_E, whereas it will have a trivial impact on R_t. A small impact angle will likely cause the rebound angle to exceed the impact angle, which usually causes a higher R_n and lower R_E. This leads to extreme scatter results of restitution and hinders the trajectory prediction. Hide

Tropical Cyclone (TC) Debbie crossed the northeast coast of Australia on 27 March 2017. A multi-sector consortium collected data throughout the event to produce a holistic picture of hazards and impacts at the coast. While water levels and waves were unprecedented for this area since monitoring began, TC Debbie can be regarded a near-miss in terms of widespread coastal flooding. This work provides a rare case study of cross-sector data sharing in a natural hazard context in Australia. Hide

Natural hazard losses are sensitive to the dependency between extreme values of the hazard variable at different spatial locations, hence it is important to correctly identify and quantify dependency to avoid poor quantification of risk. Through application to a large dataset of windstorm hazard footprints, this study demonstrates how extreme value methods can be used in a novel way to explore and quantify extremal dependency in hazards and the impact this has on the resulting hazard losses. Hide