The long-term effect of strong earthquakes on the geological hazards in mountainous areas is an underestimated issue, but the integrated use of field monitoring, remote sensing and real-time predictive modelling can help to set-up effective early warning systems, provide timely alarms, optimize rescue operations and perform more accurate secondary hazard assessments. With this paper we wish to stimulate an open discussion on post-seismic slope stability and on its implications for policy makers. Hide

Discharge forecasts are affected by meteorological and hydrological uncertainties, particularly difficult to handle when dealing with Mediterranean flash-flood. In this work, an intercomparison of two hydrometeorological ensemble strategies is presented for heavy precipitation events that affected semi-arid Spanish catchments. Both stategies are more beneficial than a deterministic approach when conveying information to end-users. Their skill is enhanced by shorter forecasting lead-times. Hide

Flood loss modelling is subject to large uncertainty that is often neglected. Most models are deterministic, and large disparities exist among them. Adopting a single model may lead to inaccurate loss estimates and sub-optimal decision-making. This paper proposes the use of multi-model ensembles to address such issues. We demonstrate that this can be a simple and pragmatic approach to obtain more accurate loss estimates and reliable probability distributions of model uncertainty. Hide

We present a procedure that allows the operational generation of daily forecasts of fire danger over Mediterranean Europe. The procedure combines historical information about radiative energy released by fire events with daily meteorological forecasts. Results obtained show that about 80 % of severe events releasing daily energy above 10 000 GJ belong to the Extreme class of fire danger. The procedure is expected to assist in wildfire management and in decision making on prescribed burning. Hide

One of the main volcanic processes affecting road infrastructure are lahars, which are flows of water and volcanic material running down the slopes of a volcano. In this paper, a bridge failure model due to lahars is proposed and, based on this, fragility curves are developed and parameterized. The fragility curves were validated for a 95 % confidence level using empirical data. Validated models confirm that decks fail mainly due to piers and/or abutment overturning rather than sliding forces. Hide

The paper attempts at evolving a new technique for assessing current state of land degradation. Assessment of current state of land degradation is difficult because this phenomena includes complex process. This assessment using RS and GIS seems to be more realistic in finding the degree of degradation because it is more related to its impact on land productivity. It is hoped that this attempt, which is the first attempt of its kind in the world, will be found applicable for other regions. Hide

This study illustrates the development and implementation of a novel rapid response storm impact survey that combined the use of drone based aerial photogrammetry with numerical modeling. The comprehensive approach employed in this pilot case study was conducted on the Emilia-Romagna coast (Italy), in the immediate aftermath of an extreme storm event that impacted the shoreline on the 5th–6th February 2015 called the Saint Agatha Storm. Hide

By analysing a comprehensive loss dataset of affected private households after a recent river flood event in Northern Italy, we tackle the problem of flood damage estimation in Emilia-Romagna (Italy). We develop empirical uni- and multi-variable loss models for residential sector. Outcomes highligh that the latter seem to outperform the first ones and, in addition, results show a higher accuracy of uni-variable models based on local data compared to literature ones derived for different context. Hide

The likelihood of severe weather events in synoptically weakly forced thunderstorm (WFT) environments is best characterized by lapse-rate-based parameters. These measures, also among the most accurate model-derived variables, are posited to best capture the subtle convective environmental differences that favor WFT severity. Forecasters should consider weighting their WFT forecasts in favor of lapse-rate-based parameters over others may be more sensitive to model biases. Hide

The objective of this study is to test and evaluate the following FFDRS, to propose possible modifications that would better adapt these systems to the Mediterranean conditions. The implemented forest fire danger rating systems are the Canadian Forest Fire Danger Rating System (CFFDRS), and Keetch-Byram Drought Index (KBDI) of the American National Forest Fire Danger Rating System (NFFDRS). Hide

Remotely Piloted Aerial Systems can acquire on-demand ultra-high resolution images that can be used for the identification of active processes like landslides or volcanic activities but also for the definition of effects of earthquakes, wildfires and floods. In this paper, we present a review of published literature that describes experimental methodologies developed for the study and monitoring of natural hazards. Hide

The two contrary high-impact weather and climate events in the southern part of China occurred during the 1982/1983 and 2009/2010 cold season, additionally, the prominent climate patterns in the boreal winter-the North Atlantic Oscillation (NAO) and the two types of El Nino were under way. Based on previous studies, we made a further investigation on how the NAO and the El Nino worked together to make the two special events, including the asymmetric relationship of NAO with two types of El Nino. Hide

The multivariate evaluation method was applied to establish a landslide susceptibility assessment model along mountains roads. The relationships between the rainfall index, instability index, and landslide occurrence indicate that for a high instability index, even a small rainfall event could trigger a landslide. The instability index thus can effectively reflect landslide susceptibility. The results could serve as a reference for the prevention and mitigation of slope disasters on hillsides. Hide

Debris flow early warning always based on well calibrated rainfall thresholds. While for area where historical data is very insufficent to determine a rainfall threshold, it is necessary to develop a method to obtain the threshold by simplily using limited data. A quantitive method, a new thinking, to calculate the rainfall thershold is developed in this study, which combined the initiation mechanism of hydraulic-driven debris flow with the runoff yield and concentration laws of the watershed. Hide

We propose a method to evaluate a French document effectiveness made by mayors and addressed to the public in order to provide information on major hazards. Our results highlight potential dysfunctions of the document, their causes and consequences and list detection elements to identify those dysfunctions. Those detections elements are about three types (content, form and regulatory compliance) and will be used to build a future evaluation effectiveness model as a decision-aid tool for mayors. Hide

The aim of this paper is to evaluate the debris flow occurrence thresholds of the rainfall intensity-duration in the earthquake-affected areas of Sichuan province over the rainy seasons from 2012 to 2014. it is clear that radar-based rainfall estimate and threshold supplement the monitoring gap of EWS where rain gauge is scarce. A better understanding of relationship between rainfall and debris flow initiation can be enhanced by the radar with highly spatiotempral resolution. Hide

The objective of this research is to improve an index originally developed to assess physical consequences of a considered hazard, by including socio-economic characteristics of population information. Data from the French Census data and a survey on risk perception (questionnaires) were used to propose an index taking into account the three main phases of risk management: preparedness, crisis management and recovery. Hide

This study looks at the importance of coral reefs and sand dunes in protecting the coast against flooding by storms. Many reefs and dunes are being degraded by human activities, making coastal areas more vulnerable. A computer model is used to look at the effects of the reef and dune degradation on coastal flooding in Puerto Morelos, Mexico. Results show that the conservation of both the reef and dune is important to protect the coast and decrease infrastructure losses. Hide

We investigate the influence of uncertain identification of triggering instants on landslide early warning thresholds. Different realistic scenarios of landslide data retrieval are hypothesized to simulate uncertainty in triggering instants. Combined impacts of uncertainty respect to temporal discretization of data (hourly or daily) and criteria for singling-out rainfall events are assessed as well. Results show that thresholds can be significantly affected by these uncertainty sources. Hide

Large boulders have been found on platforms that conform the rocky coastline of Minorca Island (Balearic Islands), several tenths of meters from the edge of the cliff, up to 15 m above the sea level, and kilometres away from any inland escarpment. The age of the boulders, thedirection of imbrication and the estimation of run-up necessary for their placement, indicate dislodging and transport by North Africa tsunami waves that hit the coastline of Minorca. Hide

The paper presents a statistical analysis of socio-economic factors influencing vulnerability and exposure to severe weather. By means of statistical modelling, the risks of weather impacts can be predicted on very high spatial resolutions. Such model can serve as a basis for a broad range of tools or applications in emergency management and planning and thus might help to enhance resilience to severe weather. Hide

The infrequent coinciding of several hydrometeorological conditions common to the Western Boreal Plain, including low autumn soil moisture, modest snowpack, lack of spring precipitation, and high spring air temperatures and winds, ultimately led to the widespread Horse River Fire in May of 2016. Monitoring antecedent soil moisture would aid management strategies in producing of more accurate overwintered drought code calculations, providing early warning signals ahead of spring wildfire seasons. Hide

We developed fragility functions of aquaculture rafts and eelgrass based on damage data and numerical simulation of the 2011 Great East Japan tsunami. These fragility functions explain damage characteristics of both items against tsunami flow velocity. By understanding these characteristics, damage estimation and loss assessment as well as marine/fishery disaster mitigation plan and management in other areas of the world from future tsunamis can be implemented. Hide

Global assessments of coastal flooding are based on the assumption that water propagation follows a bathtub pattern across the floodplain. Using a global model we find that this assumption can lead to overestimation of impacts, with an uncertainty range that can be of equal magnitude to uncertainties related to future sea-level rise. Our results highlight the importance of improving the representation of the spatial/temporal variation of water levels across floodplains of different landcover. Hide

Recently, landslides affecting pyroclastic covers of Campania Region induced victims and huge costs. Then, the development of Early Warning Systems represents a key issue for the area. However, the features of such soils make challenging the development of reliable predictive tools. The relevance of accounting for evaporative losses in slope hydrological balance regulating safety conditions is then discussed. To this aim, the landslide occurred in Nocera Inferiore in 2005 is used as test case. Hide

The study of a historical tornado that occurred about 100 years ago was motivated by the fact that rich photo material of the inflicted damage was available. It is important to rate especially strong tornadoes, because their number is in general low, and statistics of the frequency for such events and the subsequent risk assessment heavily rely on a sound data basis. We found out that the tornado reached intensity F4 on the Fujita Scale (maximum winds around 105 m/s) and caused 34 fatalities. Hide

In 2010 a sinkhole opened up in the urban area of Schmalkalden, Germany. Shear wave reflection seismic profiles were carried out around the sinkhole to investigate the reasons for the collapse. A strike-slip fault and a fracture network were identified that serve as fluid pathways for water leaching soluble rocks near the surface. The more complex the fault geometry and the more interaction between faults, the more fractures are generated and the more prone to sinkhole occurrence is the area. Hide

Flood risk estimates are characterised by significant uncertainties; accordingly, evaluating the reliability of such estimates (i.e. validating flood risk models) is crucial. Here, we discuss the state of art of flood risk models validation with the aim of identifying policy and research recommendations towards promoting more common practice of validation. The main conclusions from this review can be summarised as the need of higher quality data to perform validation and of benchmark solutions. Hide

42 % of India's landmass prone to landslides falls in North East Himalaya. One such majorly affected area is Chibo Pashyor located in Darjeeling Himalayas in the state of West Bengal, India. Early warning systems due to rainfall induced landslides has not yet been attempted in this region. This paper is an attempt towards the use of hydrological model which would be an initial step towards setting up of early warning system with an objective to protect human lives from rain-induced landslides. Hide

We proposed an integrated simulation including rainfall, landslides, and debris flows. In this simulation, the chain process is considered, and the potential effect or likely impact of compound disaster are also discussed on a watershed scale. Under extreme scenarios, the compound disaster becomes more series in our results and lead to increasing risk of stable water supply, isolated village effect, and other secondary disasters. A practical reference could be provided for further policy-making. Hide

This paper discusses how uncertainties resulting from lack of knowledge are considered in a number of different natural hazard areas including floods, landslides and debris flows, dam safety, droughts, earthquakes, tsunamis, volcanic ash clouds and pyroclastic flows, and wind storms. Since every analysis is necessarily conditional on the assumptions made about the nature of sources of such uncertainties it is also important to follow the guidelines for good practice suggested in Paper 2. Hide

Part 1 of this paper has discussed the uncertainties arising from gaps in knowledge or limited understanding of the processes involved in different natural hazard areas. These are the epistemic uncertainties that can be difficult to constrain, especially in terms of event or scenario probabilities. A conceptual framework for good practice in dealing with epistemic uncertainties is outlined and implications of applying the principles to natural hazard science are discussed. Hide