ALBERT

Description: Statistical detection and modeling of the over-dispersion of winter storm occurrence Natural Hazards and Earth System Science, 15, 1757-1761, 2015 Author(s): M. Raschke In this communication, I improve the detection and modeling of the over-dispersion of winter storm occurrence. For this purpose, the generalized Poisson distribution and the Bayesian information criterion are introduced; the latter is used for statistical model selection. Moreover, I replace the frequently used dispersion statistics by an over-dispersion parameter which does not depend on the considered return period of storm events. These models and methods are applied in order to properly detect the over-dispersion in winter storm data for Germany, carrying out a joint estimation of the distribution models for different samples.

Description: Impacts on wave-driven harbour agitation due to climate change in Catalan ports Natural Hazards and Earth System Science, 15, 1695-1709, 2015 Author(s): J. P. Sierra, M. Casas-Prat, M. Virgili, C. Mösso, and A. Sánchez-Arcilla The objective of the present work is to analyse how changes in wave patterns due to the effect of climate change can affect harbour agitation (oscillations within the port due to wind waves). The study focuses on 13 harbours located on the Catalan coast (NW Mediterranean) using a methodology with general applicability. To obtain the patterns of agitation, a Boussinesq-type model is used, which is forced at the boundaries by present/future offshore wave conditions extracted from recently developed high-resolution wave projections in the NW Mediterranean. These wave projections were obtained with the SWAN model forced by present/future surface wind fields projected, respectively, by five different combinations of global and regional circulation models (GCMs and RCMs) for the A1B scenario. The results show a general slight reduction in the annual average agitation for most of the ports, except for the northernmost and southernmost areas of the region, where a slight increase is obtained. A seasonal analysis reveals that the tendency to decrease is accentuated in winter. However, the inter-model variability is large for both the winter and the annual analysis. Conversely, a general increase with a larger agreement among models is found during summer, which is the period with greater activity in most of the studied ports (marinas). A qualitative assessment of the factors of variability seems to indicate that the choice of GCM tends to affect the spatial pattern, whereas the choice of RCM induces a more homogeneous bias over the regional domain.

Description: Towards predictive data-driven simulations of wildfire spread – Part II: Ensemble Kalman Filter for the state estimation of a front-tracking simulator of wildfire spread Natural Hazards and Earth System Science, 15, 1721-1739, 2015 Author(s): M. C. Rochoux, C. Emery, S. Ricci, B. Cuenot, and A. Trouvé This paper is the second part in a series of two articles, which aims at presenting a data-driven modeling strategy for forecasting wildfire spread scenarios based on the assimilation of the observed fire front location and on the sequential correction of model parameters or model state. This model relies on an estimation of the local rate of fire spread (ROS) as a function of environmental conditions based on Rothermel's semi-empirical formulation, in order to propagate the fire front with an Eulerian front-tracking simulator. In Part I, a data assimilation (DA) system based on an ensemble Kalman filter (EnKF) was implemented to provide a spatially uniform correction of biomass fuel and wind parameters and thereby, produce an improved forecast of the wildfire behavior (addressing uncertainties in the input parameters of the ROS model only). In Part II, the objective of the EnKF algorithm is to sequentially update the two-dimensional coordinates of the markers along the discretized fire front, in order to provide a spatially distributed correction of the fire front location and thereby, a more reliable initial condition for further model time-integration (addressing all sources of uncertainties in the ROS model). The resulting prototype data-driven wildfire spread simulator is first evaluated in a series of verification tests using synthetically generated observations; tests include representative cases with spatially varying biomass properties and temporally varying wind conditions. In order to properly account for uncertainties during the EnKF update step and to accurately represent error correlations along the fireline, it is shown that members of the EnKF ensemble must be generated through variations in estimates of the fire's initial location as well as through variations in the parameters of the ROS model. The performance of the prototype simulator based on state estimation (SE) or parameter estimation (PE) is then evaluated by comparison with data taken from a reduced-scale controlled grassland fire experiment. Results indicate that data-driven simulations are capable of correcting inaccurate predictions of the fire front location and of subsequently providing an optimized forecast of the wildfire behavior at future lead times. The complementary benefits of both PE and SE approaches, in terms of analysis and forecast performance, are also emphasized. In particular, it is found that the size of the assimilation window must be specified adequately with the persistence of the model initial condition and/or with the temporal and spatial variability of the environmental conditions in order to track sudden changes in wildfire behavior. The present prototype data-driven forecast system is still at an early stage of development. In this regard, this preliminary investigation provides valuable information on how to combine observations with a fire spread model in an efficient way, as well as guidelines to design the future system evolution in order to meet the operational requirements of wildfire spread monitoring.

Description: A method for predicting the factor of safety of an infinite slope based on the depth ratio of the wetting front induced by rainfall infiltration Natural Hazards and Earth System Science, 15, 1835-1849, 2015 Author(s): B.-G. Chae, J.-H. Lee, H.-J. Park, and J. Choi Most landslides in Korea are classified as shallow landslides with an average depth of less than 2 m. These shallow landslides are associated with the advance of a wetting front in the unsaturated soil due to rainfall infiltration, which results in an increase in water content and a reduction in the matric suction in the soil. Therefore, this study presents a modified equation of infinite slope stability analysis based on the concept of the saturation depth ratio to analyze the slope stability change associated with the rainfall on a slope. A rainfall infiltration test in unsaturated soil was performed using a column to develop an understanding of the effect of the saturation depth ratio following rainfall infiltration. The results indicated that the rainfall infiltration velocity due to the increase in rainfall in the soil layer was faster when the rainfall intensity increased. In addition, the rainfall infiltration velocity tends to decrease with increases in the unit weight of soil. The proposed model was applied to assess its feasibility and to develop a regional landslide susceptibility map using a geographic information system (GIS). For that purpose, spatial databases for input parameters were constructed and landslide locations were obtained. In order to validate the proposed approach, the results of the proposed approach were compared with the landslide inventory using a ROC (receiver operating characteristics) graph. In addition, the results of the proposed approach were compared with the previous approach used: a steady-state hydrological model. Consequently, the approach proposed in this study displayed satisfactory performance in classifying landslide susceptibility and showed better performance than the steady-state approach.

Description: Regional trends and controlling factors of fatal landslides in Latin America and the Caribbean Natural Hazards and Earth System Science, 15, 1821-1833, 2015 Author(s): S. A. Sepúlveda and D. N. Petley A new data set of landslides that caused loss of life in Latin America and the Caribbean in the 10-year period from 2004 and 2013 inclusive has been compiled, providing new insight into the impact of landslides in this key part of the world. This data set indicates that in the 10-year period a total of 11 631 people lost their lives across the region in 611 landslides. The geographical distribution of the landslides is highly heterogeneous, with areas of high incidence in parts of the Caribbean (most notably Haiti), Central America, Colombia, and southeast Brazil. There is significant interannual variation in the number of landslides, with the El Niño/La Niña cycle emerging as a key control. Our analysis suggests that on a continental scale the mapped factors that best explain the observed distribution are topography, annual precipitation and population density. On a national basis we have compared the occurrence of fatality-inducing landslide occurrence with the production of locally authored research articles, demonstrating that there is a landslide research deficit in Latin America and the Caribbean. Understanding better the mechanisms, distribution causes and triggers of landslides in Latin America and the Caribbean must be an essential first step towards managing the hazard.

Description: Drought assessment in the Dongliao River basin: traditional approaches vs. generalized drought assessment index based on water resources systems Natural Hazards and Earth System Science, 15, 1889-1906, 2015 Author(s): B. S. Weng, D. H. Yan, H. Wang, J. H. Liu, Z. Y. Yang, T. L. Qin, and J. Yin Drought is firstly a resource issue, and with its development it evolves into a disaster issue. Drought events usually occur in a determinate but a random manner. Drought has become one of the major factors to affect sustainable socioeconomic development. In this paper, we propose the generalized drought assessment index (GDAI) based on water resources systems for assessing drought events. The GDAI considers water supply and water demand using a distributed hydrological model. We demonstrate the use of the proposed index in the Dongliao River basin in northeastern China. The results simulated by the GDAI are compared to observed drought disaster records in the Dongliao River basin. In addition, the temporal distribution of drought events and the spatial distribution of drought frequency from the GDAI are compared with the traditional approaches in general (i.e., standard precipitation index, Palmer drought severity index and rate of water deficit index). Then, generalized drought times, generalized drought duration, and generalized drought severity were calculated by theory of runs. Application of said runs at various drought levels (i.e., mild drought, moderate drought, severe drought, and extreme drought) during the period 1960–2010 shows that the centers of gravity of them all distribute in the middle reaches of Dongliao River basin, and change with time. The proposed methodology may help water managers in water-stressed regions to quantify the impact of drought, and consequently, to make decisions for coping with drought.

Description: Hydroelastic analysis of ice shelves under long wave excitation Natural Hazards and Earth System Science, 15, 1851-1857, 2015 Author(s): T. K. Papathanasiou, A. E. Karperaki, E. E. Theotokoglou, and K. A. Belibassakis The transient hydroelastic response of an ice shelf under long wave excitation is analysed by means of the finite element method. The simple model, presented in this work, is used for the simulation of the generated kinematic and stress fields in an ice shelf, when the latter interacts with a tsunami wave. The ice shelf, being of large length compared to its thickness, is modelled as an elastic Euler-Bernoulli beam, constrained at the grounding line. The hydrodynamic field is represented by the linearised shallow water equations. The numerical solution is based on the development of a special hydroelastic finite element for the system of governing of equations. Motivated by the 2011 Sulzberger Ice Shelf (SIS) calving event and its correlation with the Honshu Tsunami, the SIS stable configuration is studied. The extreme values of the bending moment distribution in both space and time are examined. Finally, the location of these extrema is investigated for different values of ice shelf thickness and tsunami wave length.

Description: Pre-earthquake magnetic pulses Natural Hazards and Earth System Science, 15, 1873-1880, 2015 Author(s): J. Scoville, J. Heraud, and F. Freund A semiconductor model of rocks is shown to describe unipolar magnetic pulses, a phenomenon that has been observed prior to earthquakes. These pulses are suspected to be generated deep in the Earth's crust, in and around the hypocentral volume, days or even weeks before earthquakes. Their extremely long wavelength allows them to pass through kilometers of rock. Interestingly, when the sources of these pulses are triangulated, the locations coincide with the epicenters of future earthquakes. We couple a drift-diffusion semiconductor model to a magnetic field in order to describe the electromagnetic effects associated with electrical currents flowing within rocks. The resulting system of equations is solved numerically and it is seen that a volume of rock may act as a diode that produces transient currents when it switches bias. These unidirectional currents are expected to produce transient unipolar magnetic pulses similar in form, amplitude, and duration to those observed before earthquakes, and this suggests that the pulses could be the result of geophysical semiconductor processes.

Description: Mediterranean cyclone characteristics related to precipitation occurrence in Crete, Greece Natural Hazards and Earth System Science, 15, 1807-1819, 2015 Author(s): V. Iordanidou, A. G. Koutroulis, and I. K. Tsanis The characteristics of the cyclone tracks that caused precipitation events of variable intensity for the period 1979–2011 over the island of Crete are presented. The data set used for cyclone identification is the 0.5° × 0.5°, 30 years European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim mean sea-level pressure. Cyclone characteristics are calculated with the aid of the Melbourne University algorithm (MS scheme). Daily precipitation data from a dense gauging network over the island of Crete are also used for the classification of the precipitation events in terms of rain accumulation (intensity). Daily precipitation is classified in three categories and the associated cyclones are chosen according to their distance from Crete island. The seasonal and annual cycle of the physical characteristics of the cyclone tracks are investigated with respect to the cyclones' relative position to the island of Crete. It was found that cyclones affecting Crete most frequently approach from the western side of the island and the actual cyclone centers associated with precipitation events are usually located northwest and southeast of the Crete domain. Cyclone-induced rainfall increases in function to cyclones' depth, radius and propagation velocity increase as well as cyclones' pressure decrease. Spring cyclones that affect Crete with rainfall present lower pressures and higher cyclone propagation velocity in contrast to the ones associated with winter and autumn precipitation events. The examination of the relation between cyclone characteristics and precipitation occurrence provides valuable information related to forecasting potential and management of the water resources and the rainfall extremes.

Description: Probabilistic hurricane-induced storm surge hazard assessment in Guadeloupe, Lesser Antilles Natural Hazards and Earth System Science, 15, 1711-1720, 2015 Author(s): Y. Krien, B. Dudon, J. Roger, and N. Zahibo Current storm surge hazard maps in the French West Indies are essentially based on simple statistical methods using limited historical data and early low-resolution models which do not take the effect of waves into account. In this paper, we infer new 100-year and 1000-year surge levels in Guadeloupe from the numerical modelling of storm surges induced by a large set of synthetic events that are in statistical agreement with features of historical hurricanes in the North Atlantic Basin between 1980 and 2011. Computations are performed using the wave-current coupled model ADCIRC–SWAN with high grid resolutions (up to 40–60 m) in the coastal and wave dissipation areas. This model is validated against observations during past events such as hurricane HUGO (1989). Results are generally found to be in reasonable agreement with past studies in areas where surge is essentially wind-driven, but found to differ significantly in coastal regions where the transfer of momentum from waves to the water column constitutes a non-negligible part of the total surge. The methodology, which can be applied to other islands in the Lesser Antilles, allows storm surge level maps to be obtained that can be of major interest for coastal planners and decision makers in terms of risk management.

Description: Hydrochemical characteristics of hot spring waters in the Kangding district related to the Lushan M S = 7.0 earthquake in Sichuan, China Natural Hazards and Earth System Science, 15, 1149-1156, 2015 Author(s): Z. Chen, X. Zhou, J. Du, C. Xie, L. Liu, Y. Li, L. Yi, H. Liu, and Y. Cui Hydrogeochemistry of 10 hot springs in the Kangding district was investigated by analyzing cation and anion concentrations in the spring water. The water samples were collected in the 5 days after the Lushan M S = 7.0 earthquake, which occurred on 20 April 2013. The spring waters are classified into seven chemical types based on their hydrochemical compositions. Compared with hydrochemical data before the Lushan earthquake, concentrations of Ca 2+ , HCO 3 - and total dissolved solid (TDS) in water samples from the Guanding, Erdaoqiao, Gonghe, Erhaoying, Tianwanhe and Caoke springs significantly increased, which may be the result of a greater increase in groundwater from carbonate rocks, and water–carbonate rock interactions, enhanced by the increment of CO 2 . Concentrations of Na + , Cl - and SO 4 2- in water samples from the Guanding, Zheduotang, Xinxing and Gonghe springs decreased, indicating a dilution of shallow waters. Concentrations of Na + and SO 4 2- in water samples from the Erhaoying spring water increased, which may be attributed to water–granite interactions enhanced by H 2 S. The results indicated that hydrochemical components of spring water could be used as an effective indicator for earthquakes.

Description: Preface: Current advances in analysis, modelling and mitigation of the costs of natural hazards Natural Hazards and Earth System Science, 15, 1157-1162, 2015 Author(s): H. Kreibich, L. M. Bouwer, and R. Schwarze

Description: How historical information can improve estimation and prediction of extreme coastal water levels: application to the Xynthia event at La Rochelle (France) Natural Hazards and Earth System Science, 15, 1135-1147, 2015 Author(s): T. Bulteau, D. Idier, J. Lambert, and M. Garcin The knowledge of extreme coastal water levels is useful for coastal flooding studies or the design of coastal defences. While deriving such extremes with standard analyses using tide-gauge measurements, one often needs to deal with limited effective duration of observation which can result in large statistical uncertainties. This is even truer when one faces the issue of outliers, those particularly extreme values distant from the others which increase the uncertainty on the results. In this study, we investigate how historical information, even partial, of past events reported in archives can reduce statistical uncertainties and relativise such outlying observations. A Bayesian Markov chain Monte Carlo method is developed to tackle this issue. We apply this method to the site of La Rochelle (France), where the storm Xynthia in 2010 generated a water level considered so far as an outlier. Based on 30 years of tide-gauge measurements and 8 historical events, the analysis shows that (1) integrating historical information in the analysis greatly reduces statistical uncertainties on return levels (2) Xynthia's water level no longer appears as an outlier, (3) we could have reasonably predicted the annual exceedance probability of that level beforehand (predictive probability for 2010 based on data until the end of 2009 of the same order of magnitude as the standard estimative probability using data until the end of 2010). Such results illustrate the usefulness of historical information in extreme value analyses of coastal water levels, as well as the relevance of the proposed method to integrate heterogeneous data in such analyses.

Description: READY: a web-based geographical information system for enhanced flood resilience through raising awareness in citizens Natural Hazards and Earth System Science, 15, 1645-1658, 2015 Author(s): R. Albano, A. Sole, and J. Adamowski As evidenced by the EU Floods Directive (2007/60/EC), flood management strategies in Europe have undergone a shift in focus in recent years. The goal of flood prevention using structural measures has been replaced by an emphasis on the management of flood risks using non-structural measures. One implication of this is that public authorities alone not only take responsibility for flood management. A broader range of stakeholders, who may personally experience the negative effects of flooding, also take on responsibility for protecting themselves. Therefore, it is vital that information concerning flood risks is conveyed to those who may be affected in order to facilitate the self-protection of citizens. Experience shows that problems persist even where efforts have been made to communicate flood risks. There is a need for the development of new tools that are able to rapidly disseminate flood-risk information to the general public. To be useful these tools must be able to present information relevant to the location of the user. Moreover, the content and design of the tool need to be adjusted to laypeople's needs. Dissemination and communication influence both people's access to and understanding of natural risk information. Such a tool could be a useful aid to effective management of flood risks. To address this gap, a web-based geographical information system (WebGIS) has been developed through the collaborative efforts of a group of scientists, hazard and risk analysts and managers, GIS analysts, system developers and communication designers. This tool, called "READY: Risk, Extreme Events, Adaptation, Defend Yourself", aims to enhance the general public knowledge of flood risk, making citizens more capable of responding appropriately during a flood event. The READY WebGIS has allowed for the visualization and easy querying of a complex hazard and risk database thanks to a high degree of interactivity and easily read maps. In this way, READY has enabled fast exploration of alternative flood scenarios or past calamitous events. Combined also with a system of graphic symbols designed ad hoc for communication of self-protection behaviours, it is believed READY could lead to an increase in citizen participation, informed discussion and consensus building. The platform has been developed for a site-specific application: the Basilicata region, Italy, has been selected as pilot application area. The goal of the prototype is to raise citizen awareness of flood risks and to build social capacity and enhanced resilience to flood events.

Description: Scenario-based numerical modelling and the palaeo-historic record of tsunamis in Wallis and Futuna, Southwest Pacific Natural Hazards and Earth System Science, 15, 1763-1784, 2015 Author(s): G. Lamarche, S. Popinet, B. Pelletier, J. Mountjoy, J. Goff, S. Delaux, and J. Bind We investigated the tsunami hazard in the remote French territory of Wallis and Futuna, Southwest Pacific, using the Gerris flow solver to produce numerical models of tsunami generation, propagation and inundation. Wallis consists of the inhabited volcanic island of Uvéa that is surrounded by a lagoon delimited by a barrier reef. Futuna and the island of Alofi form the Horn Archipelago located ca. 240 km east of Wallis. They are surrounded by a narrow fringing reef. Futuna and Alofi emerge from the North Fiji Transform Fault that marks the seismically active Pacific-Australia plate boundary. We generated 15 tsunami scenarios. For each, we calculated maximum wave elevation (MWE), inundation distance and expected time of arrival (ETA). The tsunami sources were local, regional and distant earthquake faults located along the Pacific Rim. In Wallis, the outer reef may experience 6.8 m-high MWE. Uvéa is protected by the barrier reef and the lagoon, but inundation depths of 2–3 m occur in several coastal areas. In Futuna, flow depths exceeding 2 m are modelled in several populated areas, and have been confirmed by a post-September 2009 South Pacific tsunami survey. The channel between the islands of Futuna and Alofi amplified the 2009 tsunami, which resulted in inundation distance of almost 100 m and MWE of 4.4 m. This first ever tsunami hazard modelling study of Wallis and Futuna compares well with palaeotsunamis recognised on both islands and observation of the impact of the 2009 South Pacific tsunami. The study provides evidence for the mitigating effect of barrier and fringing reefs from tsunamis.

Description: Predicting storm-triggered debris flow events: application to the 2009 Ionian Peloritan disaster (Sicily, Italy) Natural Hazards and Earth System Science, 15, 1785-1806, 2015 Author(s): M. Cama, L. Lombardo, C. Conoscenti, V. Agnesi, and E. Rotigliano The main assumption on which landslide susceptibility assessment by means of stochastic modelling lies is that the past is the key to the future. As a consequence, a stochastic model able to classify past known landslide events should be able to predict a future unknown scenario as well. However, storm-triggered multiple debris flow events in the Mediterranean region could pose some limits on the operative validity of such an expectation, as they are typically resultant of a randomness in time recurrence and magnitude and a great spatial variability, even at the scale of small catchments. This is the case for the 2007 and 2009 storm events, which recently hit north-eastern Sicily with different intensities, resulting in largely different disaster scenarios. The study area is the small catchment of the Itala torrent (10 km 2 ), which drains from the southern Peloritani Mountains eastward to the Ionian Sea, in the territory of the Messina province (Sicily, Italy). Landslides have been mapped by integrating remote and field surveys, producing two event inventories which include 73 debris flows, activated in 2007, and 616 debris flows, triggered by the 2009 storm. Logistic regression was applied in order to obtain susceptibility models which utilize a set of predictors derived from a 2 m cell digital elevation model and a 1 : 50 000 scale geologic map. The research topic was explored by performing two types of validation procedures: self-validation, based on the random partition of each event inventory, and chrono-validation, based on the time partition of the landslide inventory. It was therefore possible to analyse and compare the performances both of the 2007 calibrated model in predicting the 2009 debris flows (forward chrono-validation), and vice versa of the 2009 calibrated model in predicting the 2007 debris flows (backward chrono-validation). Both of the two predictions resulted in largely acceptable performances in terms of fitting, skill and reliability. However, a loss of performance and differences in the selected predictors arose between the self-validated and the chrono-validated models. These are interpreted as effects of the non-linearity in the domain of the trigger intensity of the relationships between predictors and slope response, as well as in terms of the different spatial paths of the two triggering storms at the catchment scale.

Description: Review Article: Atmospheric conditions inducing extreme precipitation over the eastern and western Mediterranean Natural Hazards and Earth System Sciences, 15, 2525-2544, 2015 Author(s): U. Dayan, K. Nissen, and U. Ulbrich This review discusses published studies of heavy rainfall events over the Mediterranean Basin, combining them in a more general picture of the dynamic and thermodynamic factors and processes that produce heavy rain storms. It distinguishes the western and eastern Mediterranean in order to point out specific regional peculiarities. The crucial moisture for developing intensive convection over these regions can be originated not only from the adjacent Mediterranean Sea but also from distant upwind sources. Transport from remote sources is usually in the mid-tropospheric layers and associated with specific features and patterns of the larger-scale circulations. The synoptic systems (tropical and extratropical) that account for most of the major extreme precipitation events and the coupling of circulation and extreme rainfall patterns are presented. Heavy rainfall over the Mediterranean Basin is caused at times in concert by several atmospheric processes working at different atmospheric scales, such as local convection, upper synoptic-scale-level troughs, and mesoscale convective systems. Under tropical air-mass intrusions, convection generated by static instability seems to play a more important role than synoptic-scale vertical motions. Locally, the occurrence of torrential rains and their intensity is dependent on factors such as temperature profiles and implied instability, atmospheric moisture, and lower-level convergence.

Description: Climate change adaptation frameworks: an evaluation of plans for coastal Suffolk, UK Natural Hazards and Earth System Sciences, 15, 2511-2524, 2015 Author(s): J. Armstrong, R. Wilby, and R. J. Nicholls This paper asserts that three principal frameworks for climate change adaptation can be recognised in the literature: scenario-led (SL), vulnerability-led (VL) and decision-centric (DC) frameworks. A criterion is developed to differentiate these frameworks in recent adaptation projects. The criterion features six key hallmarks as follows: (1) use of climate model information; (2) analysis of metrics/units; (3) socio-economic knowledge; (4) stakeholder engagement; (5) adaptation of implementation mechanisms; (6) tier of adaptation implementation. The paper then tests the validity of this approach using adaptation projects on the Suffolk coast, UK. Fourteen adaptation plans were identified in an online survey. They were analysed in relation to the hallmarks outlined above and assigned to an adaptation framework. The results show that while some adaptation plans are primarily SL, VL or DC, the majority are hybrid, showing a mixture of DC/VL and DC/SL characteristics. Interestingly, the SL/VL combination is not observed, perhaps because the DC framework is intermediate and attempts to overcome weaknesses of both SL and VL approaches. The majority (57 %) of adaptation projects generated a risk assessment or advice notes. Further development of this type of framework analysis would allow better guidance on approaches for organisations when implementing climate change adaptation initiatives, and other similar proactive long-term planning.

Description: UAV-based urban structural damage assessment using object-based image analysis and semantic reasoning Natural Hazards and Earth System Science, 15, 1087-1101, 2015 Author(s): J. Fernandez Galarreta, N. Kerle, and M. Gerke Structural damage assessment is critical after disasters but remains a challenge. Many studies have explored the potential of remote sensing data, but limitations of vertical data persist. Oblique imagery has been identified as more useful, though the multi-angle imagery also adds a new dimension of complexity. This paper addresses damage assessment based on multi-perspective, overlapping, very high resolution oblique images obtained with unmanned aerial vehicles (UAVs). 3-D point-cloud assessment for the entire building is combined with detailed object-based image analysis (OBIA) of façades and roofs. This research focuses not on automatic damage assessment, but on creating a methodology that supports the often ambiguous classification of intermediate damage levels, aiming at producing comprehensive per-building damage scores. We identify completely damaged structures in the 3-D point cloud, and for all other cases provide the OBIA-based damage indicators to be used as auxiliary information by damage analysts. The results demonstrate the usability of the 3-D point-cloud data to identify major damage features. Also the UAV-derived and OBIA-processed oblique images are shown to be a suitable basis for the identification of detailed damage features on façades and roofs. Finally, we also demonstrate the possibility of aggregating the multi-perspective damage information at building level.

Description: Effects of soil settlement and deformed geometry on a historical structure Natural Hazards and Earth System Science, 15, 1051-1059, 2015 Author(s): Y. Yardım and E. Mustafaraj Protecting the historical character of a valued structure during the assessment and damage repair process is a very challenging task for many engineers. Heritage protection is complicated by a lack of design details and restrictions on sample extraction needed to obtain accurate material properties and limited studies on the restoration of certain types of historical structures. This study aims to assess the effects of soil settlement on a structure's stress concentrations and the value of laser scanning techniques on structure analysis in obtaining correct data of settlement vs. deformation. Terrestrial laser scanner (TLS) data are used to analyse the 500-year-old historical structure of Naziresha's Mosque. The obtained TLS data allow an accurate definition of the imperfect geometry patterns lying on every side of the structure. The soil profile and general crack formation together with TLS measurement proves that the structure deformed toward the south façade, where a railway and motorway are also located. Stress concentration and mode period results have a considerable difference, which highlights earthquake vulnerability and failure mechanisms and changes the strategy of possible retrofitting.

Description: On a report that the 2012 M 6.0 earthquake in Italy was predicted after seeing an unusual cloud formation Natural Hazards and Earth System Science, 15, 1061-1068, 2015 Author(s): J. N. Thomas, F. Masci, and J. J. Love Several recently published reports have suggested that semi-stationary linear-cloud formations might be causally precursory to earthquakes. We examine the report of Guangmeng and Jie (2013), who claim to have predicted the 2012 M 6.0 earthquake in the Po Valley of northern Italy after seeing a satellite photograph (a digital image) showing a linear-cloud formation over the eastern Apennine Mountains of central Italy. From inspection of 4 years of satellite images we find numerous examples of linear-cloud formations over Italy. A simple test shows no obvious statistical relationship between the occurrence of these cloud formations and earthquakes that occurred in and around Italy. All of the linear-cloud formations we have identified in satellite images, including that which Guangmeng and Jie (2013) claim to have used to predict the 2012 earthquake, appear to be orographic – formed by the interaction of moisture-laden wind flowing over mountains. Guangmeng and Jie (2013) have not clearly stated how linear-cloud formations can be used to predict the size, location, and time of an earthquake, and they have not published an account of all of their predictions (including any unsuccessful predictions). We are skeptical of the validity of the claim by Guangmeng and Jie (2013) that they have managed to predict any earthquakes.

Description: Land cover changes and forest landscape evolution (1985–2009) in a typical Mediterranean agroforestry system (high Agri Valley) Natural Hazards and Earth System Science, 15, 1201-1214, 2015 Author(s): T. Simoniello, R. Coluzzi, V. Imbrenda, and M. Lanfredi The present study focuses on the transformations of a typical Mediterranean agroforestry landscape of southern Italy (high Agri Valley – Basilicata region) that occurred over 24 years. In this period, the valuable agricultural and natural areas that compose such a landscape were subjected to intensive industry-related activities linked to the exploitation of the largest European onshore oil reservoir. Landsat imagery acquired in 1985 and 2009 were used to detect changes in forest areas and major land use trajectories. Landscape metrics indicators were adopted to characterize landscape structure and evolution of both the complex ecomosaic (14 land cover classes) and the forest/non-forest arrangement. Our results indicate a net increase of 11% of forest areas between 1985 and 2009. The major changes concern increase of all forest covers at the expense of pastures and grasses, enlargement of riparian vegetation, and expansion of artificial areas. The observed expansion of forests was accompanied by a decrease of the fragmentation levels likely due to the reduction of small glades that break forest homogeneity and to the recolonization of herbaceous areas. Overall, we observe an evolution towards a more stable configuration depicting a satisfactory picture of vegetation health.

Description: Internal structure of event layers preserved on the Andaman Sea continental shelf, Thailand: tsunami vs. storm and flash-flood deposits Natural Hazards and Earth System Science, 15, 1181-1199, 2015 Author(s): D. Sakuna-Schwartz, P. Feldens, K. Schwarzer, S. Khokiattiwong, and K. Stattegger Tsunami, storm and flash-flood event layers, which have been deposited over the last century on the shelf offshore Khao Lak (Thailand, Andaman Sea), are identified in sediment cores based on sedimentary structures, grain size compositions, Ti / Ca ratios and 210 Pb activity. Individual offshore tsunami deposits are 12 to 30 cm in thickness and originate from the 2004 Indian Ocean Tsunami. They are characterized by (1) the appearance of sand layers enriched in shells and shell debris and (2) the appearance of mud and sand clasts. Storm deposits found in core depths between 5 and 82 cm could be attributed to recent storm events by using 210 Pb profiles in conjunction with historical data of typhoons and tropical storms. Massive sand layers enriched in shells and shell debris characterize storm deposits. The last classified type of event layer represents reworked flash-flood deposits, which are characterized by a fining-upward sequence of muddy sediment. The most distinct difference between storm and tsunami deposits is the lack of mud and sand clasts, mud content and terrigenous material within storm deposits. Terrigenous material transported offshore during the tsunami backwash is therefore an important indicator to distinguish between storm and tsunami deposits in offshore environments.

Description: Development of high-resolution multi-scale modelling system for simulation of coastal-fluvial urban flooding Agnieszka Indiana Olbert, Joanne Comer, Stephen Nash, and Michael Hartnett Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-238,2016 Manuscript under review for NHESS (discussion: open, 0 comments) A novel nested flood model (MSN_Flood) is applied to simulate complex coastal-fluvial urban flooding in order to critically examine the model's capability to forecast evolution of urban inundation. The model demonstrates high accuracy of outputs without incurring the computational expense of high spatial resolution over the entire model domain. MSN_Flood provides full characteristics of water levels and flow regimes necessary for flood hazard identification and flood risk assessment.

Description: Comparison and validation of global and regional ocean forecasting systems for the South China Sea Xueming Zhu, Hui Wang, Guimei Liu, Charly Régnier, Xiaodi Kuang, Dakui Wang, Shihe Ren, Zhiyou Jing, and Marie Drévillon Nat. Hazards Earth Syst. Sci., 16, 1639-1655, doi:10.5194/nhess-16-1639-2016, 2016 This paper examined the performances of two operational ocean forecasting systems, Mercator Océan in France and SCSOFS in China, based on observed satellite and in situ data obtained in 2012. The comparison and validation are focused on the ocean circulations, the structures of temperature and salinity, and some mesoscale activities in the South China Sea. Finally, some recommendations have been proposed for both systems to improve their performances in the near future.

Description: Enhancing local action planning through quantitative flood risk analysis: a case study in Spain Jesica Tamara Castillo-Rodríguez, Ignacio Escuder-Bueno, Sara Perales-Momparler, and Juan Ramón Porta-Sancho Nat. Hazards Earth Syst. Sci., 16, 1699-1718, doi:10.5194/nhess-16-1699-2016, 2016 This article presents a method to incorporate and promote quantitative flood risk analysis to support local action planning against flooding. The conducted research work aims at providing a framework for local flood risk analysis and to support risk-informed decision-making (e.g. urban planning and development, flood risk management, civil protection). This article shows the added value of a risk-informed perspective, applied to a real case study in Spain.

Description: Meteorological factors driven glacial till changing and the associated periglacial debris flows in Tianmo Valley, southeast Tibetan Plateau Mingfeng Deng, Ningsheng Chen, and Mei Liu Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-251,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Initiation of deris flows in Tianmo valley shows annual temperature spiked and glacier retreat quickly before the three debris flows, while they did not occur when glacier retreat is sharpest, resulting from the bared glacial till is frozen as the melting of internal ice lags behind glacial retreat. The activity of the glacial till can be enhanced by prolonged high air temperature. Finally, either rainfall or continuous percolation of ice ablation water flows can generate periglacial debris flows.

Description: Analysis of slope processes in the Vallcebre landslide (Eastern Pyrenees, Spain) by means of Cross Correlation Function applied to high frequency monitoring data Marco Mulas, Jordi Corominas, Alessandro Corsini, and Jose Moya Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-253,2016 Manuscript under review for NHESS (discussion: open, 0 comments) In this work, the Cross-Correlation Function is used in order to quantitatively investigate the time-lagged correlation between high frequency monitoring data on rainfall, piezometric and displacement with the objective to evidence hydro-mechanical processes in the Vallcebre landslide (Eastern Pyrenees, Spain). The analysis highlighted and constrained in time a dual triggering mechanism in which factors controlling movement change from the upper to the lower part of the landslide.

Description: Vulnerability curves vs. vulnerability indicators: application of an indicator-based methodology for debris-flow hazards Maria Papathoma-Köhle Nat. Hazards Earth Syst. Sci., 16, 1771-1790, doi:10.5194/nhess-16-1771-2016, 2016 Two established methods for assessing the physical vulnerability of buildings to natural hazards (vulnerability indicators and vulnerability curves) are compared after beind applied at the same case study. The case study area is located in South Tyrol (Italy) and it is subject to debris flow hazard. The results indicate that both methods have advantages and disadvantages and should be used in combination rather than in isolation by practitioners.

Description: What if the 25 October 2011 event that struck Cinque Terre (Liguria) had happened in Genoa, Italy? Flooding scenarios, hazard mapping and damage estimation Francesco Silvestro, Nicola Rebora, Lauro Rossi, Daniele Dolia, Simone Gabellani, Flavio Pignone, Eva Trasforini, Roberto Rudari, Silvia De Angeli, and Cristiano Masciulli Nat. Hazards Earth Syst. Sci., 16, 1737-1753, doi:10.5194/nhess-16-1737-2016, 2016 During the autumn of 2011 two catastrophic, very intense rainfall events affected two different parts of the Liguria Region of Italy causing various flash floods. The first occurred in October and the second at the beginning of November. Both the events were characterized by very high rainfall intensities (〉 100 mm h −1 ) that persisted on a small portion of territory causing local huge rainfall accumulations (〉 400 mm 6 h −1 ). Two main considerations were made in order to set up this work. The first consideration is that various studies demonstrated that the two events had a similar genesis and similar triggering elements. The second very evident and coarse concern is that two main elements are needed to have a flash flood: a very intense and localized rainfall event and a catchment (or a group of catchments) to be affected. Starting from these assumptions we did the exercise of mixing the two flash flood ingredients by putting the rainfall field of the first event on the main catchment struck by the second event, which has its mouth in the biggest city of the Liguria Region: Genoa. A complete framework was set up to quantitatively carry out a “what if” experiment with the aim of evaluating the possible damages associated with this event. A probabilistic rainfall downscaling model was used to generate possible rainfall scenarios maintaining the main characteristics of the observed rainfall fields while a hydrological model transformed these rainfall scenarios in streamflow scenarios. A subset of streamflow scenarios is then used as input to a 2-D hydraulic model to estimate the hazard maps, and finally a proper methodology is applied for damage estimation. This leads to the estimation of the potential economic losses and of the risk level for the people that stay in the affected area. The results are interesting, surprising and in a way worrying: a rare but not impossible event (it occurred about 50 km away from Genoa) would have caused huge damages estimated between 120 and EUR 230 million for the affected part of the city of Genoa, Italy, and more than 17 000 potentially affected people.

Description: VISIR: technological infrastructure of an operational service for safe and efficient navigation in the Mediterranean Sea Gianandrea Mannarini, Giuseppe Turrisi, Alessandro D'Anca, Mario Scalas, Nadia Pinardi, Giovanni Coppini, Francesco Palermo, Ivano Carluccio, Matteo Scuro, Sergio Cretì, Rita Lecci, Paola Nassisi, and Luca Tedesco Nat. Hazards Earth Syst. Sci., 16, 1791-1806, doi:10.5194/nhess-16-1791-2016, 2016 Safety and efficiency of navigation can be enhanced through a better situational awareness at sea. We designed and realized an operational infrastructure for providing the navigators with optimal routes through various devices: PC, tablets, and smartphones. Sea-state and wind forecasts are used as inputs. Both motor- and sailboat routes are addressed by VISIR.

Description: Brief Communication: An update of the article "Modelling flood damages under climate change conditions – a case study for Germany" Fred Fokko Hattermann, Shaochun Huang, Olaf Burghoff, Peter Hoffmann, and Zbigniew W. Kundzewicz Nat. Hazards Earth Syst. Sci., 16, 1617-1622, doi:10.5194/nhess-16-1617-2016, 2016 We report that a considerable increase in flood-related losses can be expected in Germany in a future warmer climate. The general significance of the study is supported by the fact that the outcome of an ensemble of global climate models (GCMs) and regional climate models (RCMs) was used as a climate driver for a hydrological model considering more than 3000 river basins in Germany.

Description: Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts Hiroshi Takagi, Takahito Mikami, Daisuke Fujii, Miguel Esteban, and Shota Kurobe Nat. Hazards Earth Syst. Sci., 16, 1629-1638, doi:10.5194/nhess-16-1629-2016, 2016 Thin coastal dykes found in developing countries may suddenly collapse due to land subsidence, material ageing, earthquakes, a collision with vessels, etc. Such a failure could trigger a dyke-break-induced tsunami. To analyse the potential consequences of such a flooding event, a hydrodynamic model was created using the data from the authors' field surveys of a vulnerable coastal community in Jakarta. The countermeasure of using mangrove forest is also proposed to mitigate violent floods.

Description: Debris flow impact estimation on a rigid barrier Federico Vagnon and Andrea Segalini Nat. Hazards Earth Syst. Sci., 16, 1691-1697, doi:10.5194/nhess-16-1691-2016, 2016 This study has the aim of reviewing the dynamics of debris flow impact against rigid structures and providing a new simple formulation to predict peak thrust. The proposed equation differs from other formulations because it takes into account flow characteristics, material properties, and barrier dimensions. The developed model is sufficiently capable of predicting measured force during the laboratory tests.

Description: Using video games for volcanic hazard education and communication: an assessment of the method and preliminary results Lara Mani, Paul D. Cole, and Iain Stewart Nat. Hazards Earth Syst. Sci., 16, 1673-1689, doi:10.5194/nhess-16-1673-2016, 2016 Here, we aim to better understand the potential for using video games in volcanic hazard education with at-risk communities. A study using a bespoke-designed video game – St. Vincent's Volcano – was trialled on the Caribbean island of St. Vincent in 2015. Preliminary data analysis demonstrates 94 % of study participants had an improved knowledge of volcanic hazards after playing the game, leading us to conclude that video games could be a logical progression for education and outreach activities.

Description: Simple and approximate upper-limit estimation of future precipitation return-values Rasmus E. Benestad, Kajsa M. Parding, Abdelkader Mezghani, and Anita V. Dyrrdal Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-229,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We propose a strategy for quantifying the maximum effect a temperature change has on heavy precipitation amounts making use of the limited available sources of information: laws of physics, seasonal variations, mathematical estimation of probability, and large number of climate model results. An upper bound is estimated rather than most likely value.

Description: Partial reactivation of a huge deep-seated ancient rock slide: recognition, formation mechanism, and stability Minggao Tang, Qiang Xu, Yusheng Li, Runqiu Huang, Niek Rengers, and Xing Zhu Nat. Hazards Earth Syst. Sci., 16, 1719-1735, doi:10.5194/nhess-16-1719-2016, 2016 An important argument for the conclusion is the recognition of a regional compressive tectonic stress field in this area, which cannot lead to the formation of a fault graben, which needs a tensional tectonic stress field. Moreover, numerous unique geological features, sliding marks, and other relics of the ancient slide have been discovered in the field. A centrifuge model test shows that a deformation and failure process of "creep–crack–cut" and a type of "successive rotational rock slide" have occurred.

Description: Lightning risk assessment at a high spatial resolution using the resident sub-district scale: A case study in Beijing metropolitan areas Hai Bo Hu and Jing Xiao Li Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-231,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Lightning risk indexes identifying the potential number of dangerous lightning events (NDLEs) and ground sensitivity to lightning in resident sub-districts of Beijing metropolitan areas have been unprecedentedly estimated on a 5 m resolution grid. The gridded cloud to ground (CG) lightning stroke density was used in the NDLE calculation, on account of multiple contacts formed by CG lightning flash multiplicity. Meanwhile, in the NDLE estimates, the critical CG stroke gridded densities derived from the lightning location system (LLS) data were corrected for network detection efficiency (DE). This case study on resident sub-district indicates that the site-specific sensitivity to lightning, which is determined by the terrain factors related to lightning attachment, as well as lightning rod effects induced by nearby structures, differs greatly across types of underlying ground areas. The discrepancy of the NDLE which is the numerical product of sensitivity and CG stroke density, is predominated by the sensitivity on account of the relatively stationary CG stroke density in a resident sub-district scale. Conclusively, the visualization of lightning risk sensitivity and NDLE discrepancy in parts of a resident sub-district at high spatial resolution makes it convenient in risk reduction and risk control for lightning risk management.

Description: The unrest of the San Miguel volcano (El Salvador, Central America): installation of the monitoring network and observed volcano-tectonic ground deformation Alessandro Bonforte, Douglas Antonio Hernandez, Eduardo Gutiérrez, Louis Handal, Cecilia Polío, Salvatore Rapisarda, and Piergiorgio Scarlato Nat. Hazards Earth Syst. Sci., 16, 1755-1769, doi:10.5194/nhess-16-1755-2016, 2016 In this paper, we present the work done during an international cooperation between Italy and El Salvador, for implementing the multiparametric monitoring of the San Miguel volcano in El Salvador after its sudden unrest. In particular, the aim of this paper is to show and describe the installed geodetic network and to show, comment and interpret the very first detailed ground deformation data obtained on this volcano during an unrest period, useful for characterizing its unknown dynamics.

Description: Hydrodynamic modelling of coastal seas: the role of tidal dynamics in the Messina Strait, Western Mediterranean Sea Andrea Cucco, Giovanni Quattrocchi, Antonio Olita, Leopoldo Fazioli, Alberto Ribotti, Matteo Sinerchia, Costanza Tedesco, and Roberto Sorgente Nat. Hazards Earth Syst. Sci., 16, 1553-1569, doi:10.5194/nhess-16-1553-2016, 2016 This work explored the importance of considering the tidal dynamics when modelling the general circulation in the Messina Strait, a narrow passage connecting the Tyrrhenian and the Ionian Sea sub-basins in the Western Mediterranean Sea. The results highlight that tidal dynamics deeply impact the reproduction of the instantaneous and residual circulation pattern, waters thermohaline properties and transport dynamics both inside the Messina Strait and in the surrounding coastal and open waters.

Description: Heavy snow loads in Finnish forests respond regionally asymmetrically to projected climate change Ilari Lehtonen, Matti Kämäräinen, Hilppa Gregow, Ari Venäläinen, and Heli Peltola Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-184,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We studied the impact of projected climate change on the risk of snow-induced forest damage in Finland. Although winters are projected to become milder over the whole of Finland, our results suggest than in eastern and northern Finland the risk may increase while in southern and western parts of the country it is projected to decrease. This indicates that there is increasing need to consider the potential of snow damage in forest management in eastern and northern Finland.

Description: Review article: Potential application of surface methods for the monitoring of organic matter dynamics in marine systems Galja Pletikapić and Nadica Ivošević DeNardis Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-178,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We present the potential of non-invasive surface methods, the electrochemical method applied with atomic force microscopy imaging (AFM), and its application for monitoring needs undertaken in the Adriatic sea. Electrochemical approach enables simple and fast analysis of a large number of raw seawater samples due to the simultaneous differentiation of organic constituents in seawater. AFM allows direct visualization and structural organization of marine organic matter at nanometer scales.

Description: GPS-derived ground deformation (2005–2014) within the Gulf of Mexico region referred to a stable Gulf of Mexico reference frame Jiangbo Yu and Guoquan Wang Nat. Hazards Earth Syst. Sci., 16, 1583-1602, doi:10.5194/nhess-16-1583-2016, 2016 The study establishes the first local reference frame for the Gulf of Mexico region using the observations from 13 GNSS sites. The root mean square (RMS) of the velocities of the 13 reference stations achieves 0.2 mm yr −1 in the horizontal and 0.3 mm yr −1 in the vertical directions. Land subsidence, faulting, and salt dome activities in the Houston region, Mexico City, and the southeastern Louisiana region are discussed and compared.

Description: GIS analysis of effects of future Baltic sea level rise on the island of Gotland, Sweden Karin Ebert, Karin Ekstedt, and Jerker Jarsjö Nat. Hazards Earth Syst. Sci., 16, 1571-1582, doi:10.5194/nhess-16-1571-2016, 2016 Future sea level rise is inevitable. We investigate the effects of 2 m sea level rise on the island of Gotland, Sweden. In a multi-criteria analysis we analyze the quantity of infrastructure that will be inundated, and the effect of saltwater intrusion in wells. Almost 100 km 2 (3 %) of Gotland's land area will be inundated. Important touristic and nature values will be strongest affected. Well salinization will greatly increase. Administrative planning is needed to prepare for changes.

Description: TESSA: design and implementation of a platform for Situational Sea Awareness M. Scalas, P. Marra, L. Tedesco, R. Quarta, E. Cantoro, A. Tumolo, D. Rollo, and M. Spagnulo Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-166,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This article describes the architecture of Sea Situational Awareness (SSA) platform, a major asset within "TESSA", an industrial research project funded by the Italian Ministry of Education and Research. The main aim of the platform is to collect, transform and provide forecast and observational data as information suitable for delivery across a variety of channels, like web and mobile; specifically, the ability to produce and provide forecast information suitable for creating SSA-enabled applications has been a critical driving factor when designing and evolving the whole architecture. Thus, starting from functional and performance requirements, the platform architecture is described in terms of its main building blocks and flows among them: front-end components that support end-user applications and map and data analysis components that allow for serving maps and querying data. Focus is directed to key aspects and decisions about the main issues faced, like interoperability, scalability, efficiency and adaptability, but it also considers insights about future works in this and similarly related subjects. Some analysis results are also provided in order to better characterize critical issues and related solutions.

Description: Hydrodynamic characterization of past flash-flood events and their associated hazards from dendrogeomorphological evidence in Caldera de Taburiente National Park (Canary Islands, Spain) Julio Garrote, Andrés Diez-Herrero, José M. Bodoque, María A. Perucha, Pablo Mayer, and Mar Genova Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-206,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The paper shows a study assessing different flooding scenarios based on the height of scars in trees as indicators for peak discharge estimation in an ungauged fluvial basin with sand and gravel riverbed. The use of scars on trees together with the combined use of 2D hydraulic model and LIDAR topographic data, has allowed a better peak discharge estimation of January, 11–13, 1997 flash flood and its related hazards, than estimation from rainfall data. This could improve flooding risk mapping.

Description: Brief communication "Loss and Damage from a catastrophic landslide in Nepal" Kees van der Geest and Markus Schindler Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-210,2016 Manuscript under review for NHESS (discussion: open, 0 comments) In August 2014, a major landslide struck in a densely populated district 80 km northeast of Nepal's capital Kathmandu, in Sindhupalchok District. This study combines evidence from surveyes and intereviews to assess impacts, and preventive and coping measures taken. The impacts relative to annual income show that the poor lost up to 14 times their annual income, as opposed to 3 times for the non-poor. The implications of these findings for discussions surrounding loss and damage are discussed.

Description: The catastrophic landfill flowslide at Hongao dumpsite on December 20, 2015 in Shenzhen, China Qiang Xu, Dalei Peng, Weile Li, Xiujun Dong, Wei Hu, Minggao Tang, and Fangzhou Liu Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-196,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The article aims at presenting the first-hand dataset and results from the field investigation, laboratory test, and numerical analysis for the flowslide occurred on December 20, 2015, in Shenzhen, China; A devastating event resulted in significant human and property losses. The article concluded that the landfill stagnated groundwater flow and resulted in high water pressure due to the absence of drainage system with both disposal rate and amount exceeding the maximum design capacity.

Description: Global distribution of winter lightning: a threat to wind turbines and aircraft Joan Montanyà, Ferran Fabró, Oscar van der Velde, Víctor March, Earle Rolfe Williams, Nicolau Pineda, David Romero, Glòria Solà, and Modesto Freijo Nat. Hazards Earth Syst. Sci., 16, 1465-1472, doi:10.5194/nhess-16-1465-2016, 2016 Lightning is one of the major threats to modern multi-megawatt wind turbines and a concern for new generation of aircraft. Both wind turbines and aircraft can initiate lightning and very favourable conditions for lightning initiation occur in winter thunderstorms. Moreover, winter thunderstorms are characterized for producing very energetic lightning. In this paper we present the global winter lightning activity. Japan, US, Mediterranean, Argentina and New Zealand are the most active areas.

Description: SeaConditions: a web and mobile service for safer professional and recreational activities in the Mediterranean Sea G. Coppini, P. Marra, R. Lecci, N. Pinardi, S. Cretì, M. Scalas, L. Tedesco, A. D'Anca, L. Fazioli, A. Olita, G. Turrisi, C. Palazzo, G. Aloisio, S. Fiore, A. Bonaduce, Y. Kumar, S. A. Ciliberti, I. Federico, G. Mannarini, P. Agostini, R. Bonarelli, S. Martinelli, G. Verri, L. Lusito, D. Rollo, A. Cavallo, A. Tumolo, T. Monacizzo, M. Spagnulo, R. Sorgente, A. Cucco, G. Quattrocchi, M. Tonani, M. Drudi, L. Panzera, A. Navarra, and G. Negro Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-176,2016 Manuscript under review for NHESS (discussion: open, 0 comments) SeaCondition aims to support the users providing the environmental information in due time and with the adequate accuracy in the marine and coastal environment enforcing users' Sea Situational Awareness. SeaConditions consists of a web and mobile application for the provision of meteorological and oceanographic observation and forecasting products. The iOS/Android apps were downloaded by more than 105 000 users and more than 100 000 users have visited the web version ( http://www.sea-conditions.com ).

Description: Stand-Alone Tsunami Alarm Equipment Akio Katsumata, Yutaka Hayashi, Kazuki Miyaoka, Hiroaki Tsushima, Toshitaka Baba, Patricio A. Catalán, Cecilia Zelaya, Felipe Riquelme Vasquez, Rodrigo Sanchez-Olavarria, and Sergio Barrientos Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-164,2016 Manuscript under review for NHESS (discussion: open, 0 comments) One of the quickest means of tsunami evacuation is transfer to higher ground soon after strong and long ground-shaking. Strong ground motion means that the hypocenter of the event is close to the current location, and long ground-shaking means that the size of the earthquake is large. We investigated the possibility to apply this to tsunami hazard alarm using single-site observation of ground shaking.

Description: Atmospheric and ionospheric coupling phenomena related to large earthquakes M. Parrot, V. Tramutoli, Tiger J. Y. Liu, S. Pulinets, D. Ouzounov, N. Genzano, M. Lisi, K. Hattori, and A. Namgaladze Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-172,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Since tens of years perturbations have been observed in the ionosphere prior to earthquakes (between a few hours and a few days before). But the mechanism to understand how the earthquake preparation in a seismic area can induce a change in the ionosphere is the subject of intense debate. In this paper we present various atmospheric and ionospheric perturbations observed prior to large earthquakes in order to support a model of coupling between the lithosphere, the atmosphere, and the ionosphere.

Description: Regional impacts of global change: seasonal trends in extreme rainfall, run-off and temperature in two contrasting regions of Morocco Kenza Khomsi, Gil Mahe, Yves Tramblay, Mohamed Sinan, and Maria Snoussi Nat. Hazards Earth Syst. Sci., 16, 1079-1090, doi:10.5194/nhess-16-1079-2016, 2016 The study investigates trends in mean and extreme rainfall, run-off, temperature and their relationship with large-scale atmospheric circulation. It focuses on two Moroccan watersheds; Bouregreg and Tensift, using data from 1977 to 2003. Results do not show a homogeneous behaviour in the catchments; the influence of the large-scale atmospheric circulation is different and a clear spatial dependence of the trend analysis is linked to the distance from the coast and the mountains.

Description: FLOPROS: an evolving global database of flood protection standards Paolo Scussolini, Jeroen C. J. H. Aerts, Brenden Jongman, Laurens M. Bouwer, Hessel C. Winsemius, Hans de Moel, and Philip J. Ward Nat. Hazards Earth Syst. Sci., 16, 1049-1061, doi:10.5194/nhess-16-1049-2016, 2016 Assessments of flood risk, on global to local scales, are becoming more urgent with ongoing climate change and with rapid socioeconomic developments. Such assessments need information about existing flood protection, still largely unavailable. Here we present the first open-source database of FLood PROtection Standards, FLOPROS, which enables more accurate modelling of flood risk. We also invite specialists to contribute new information to this evolving database.

Description: Surface movement above an underground coal longwall mine after closure André Vervoort Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-134,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Underground coal mining induces surface movement with damage to infrastructure. The best known phenomenon is the downward movement or subsidence during the life of the mine. However, it has been observed that after the closure of the mine there is first a period of still residual subsidence, followed by an upwards movement or uplift. This uplift is the direct result of the flooding of the underground workings. By conducting this research the long term impact of mining is better quantified.

Description: The street, an area exposed to earthquakes (the Lorca case, Spain 2011) M. B. Rojo, E. Beck, and C. Lutoff Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-115,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The Lorca earthquake (Spain, 11-05-2011) caused considerable damages, including a building collapse. This earthquake killed 9 persons affected outside the buildings, on the street, and more than 300 people injured. Studying this specific human exposure requires an adapted methodolgy. This article proposes a dynamic and spatio-temporal approach of individual mobility during the seismic crisis. Its application on Lorca case shows spatial and temporal variability of individual exposure level in the street during the hours following the shake. Not really studied until now, this specific human exposure deserves more attention particularly in zones of moderate seismicity, like Euromediterranean area.

Description: Empirical Study on Drought Adaptation of Regional Rainfed Agriculture in China Zhiqiang Wang, Qing Ma, Siyu Chen, Lan Deng, and Jingyi Jiang Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-94,2016 Manuscript under review for NHESS (discussion: open, 0 comments) With global warming, the risk of agricultural drought is increasing. Through the empirical analysis of this paper, it found that farmers and the government always spontaneously adjust their development demands and take measures to adapt to environmental change, thus a dynamic agricultural drought adaptation model with the regional characteristics was formed in the area. Agricultural drought risk (R) is the function of environment (E), demand (D) and adaptation (A), or R = f (E, D, A).

Description: Research trends on hazards, disasters, risk reduction and climate change in Indonesia: a systematic literature review Riyanti Djalante Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-112,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The paper examines progress in research related hazards, risks, disasters, disaster risk reduction and management in Indonesia. It also reviews the roles of Indonesian authors in those publications. The study finds that majority of research focusses on hazards while only recently they focusses on risk reduction and management. This study recommends future research needs and capacity building in writing and collaboration between Indonesia and international researchers.

Description: From event analysis to global lessons: disaster forensics for building resilience Adriana Keating, Kanmani Venkateswaran, Michael Szoenyi, Karen MacClune, and Reinhard Mechler Nat. Hazards Earth Syst. Sci., 16, 1603-1616, doi:10.5194/nhess-16-1603-2016, 2016 We present a disaster forensics methodology: the post-event review capability (PERC), which responds to a need for learning about the successes and failures in disaster risk management (DRM) and resilience, uncovers the underlying drivers of increasing risk and makes actionable recommendations. We analyse seven PERC reports and find that across the globe policy makers and practitioners in DRM face strikingly similar challenges. These lessons highlight the importance of integrated risk reduction.

Description: An examination of land use impacts of sea level rise induced flooding Jie Song, Xinyu Fu, Yue Gu, Yujun Deng, and Zhong-Ren Peng Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-157,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We present a joint model which couples urban growth dynamics with coastal hazards. We use the SLEUTH platform to investigate three urban growth scenarios under different land use policies. We found that compact development may contribute to the region's vulnerability to sea level rise induced flooding, and that strict land development regulations may greatly mitigate such vulnerability. The findings highlight the importance of land use simulations in formulating coastal management plans.

Description: Natural hazard fatalities in Switzerland from 1946 to 2015 Alexandre Badoux, Norina Andres, Frank Techel, and Christoph Hegg Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-232,2016 Manuscript under review for NHESS (discussion: open, 0 comments) A database of fatalities caused by natural hazards in Switzerland was compiled for the period from 1946 to 2015: In 70 years, 635 events occurred causing 1023 fatalities. The most common causes of death were snow avalanches (37 %), followed by lightning (16 %), floods (12 %), windstorms (10 %), rockfalls (8 %) and landslides (7 %). The annual number of victims showed a distinct decrease over time. In comparison to other countries worldwide, the natural hazard fatality rate in Switzerland is quite low.

Description: Coastal flooding: impact of waves on storm surge during extremes. A case study for the German Bight Joanna Staneva, Kathrin Wahle, Wolfgang Koch, Arno Behrens, Luciana Fenoglio-Marc, and Emil V. Stanev Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-227,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This study addresses impact of wind, waves, tidal forcing and baroclinicity on the sea level. Their role is quantified and the results are compared with observations. The analyses of the coupled model results reveal a closer match with observations than for the stand-alone circulation model, especially during the extremes. The improved performance resulting from the new developments justifies further use of coupled models for improvement of coastal flooding predictions.

Description: Influence of expertise on rockfall hazard assessment using empirical methods Adeline Delonca, Thierry Verdel, and Yann Gunzburger Nat. Hazards Earth Syst. Sci., 16, 1657-1672, doi:10.5194/nhess-16-1657-2016, 2016 Rockfall hazard zoning analyses can be based on qualitative observations. For this reason, expertise is of great importance in determining the hazard. To test this hypothesis, an experiment is proposed to evaluate the importance of subjective assessment: three populations with different level of expertise assessed the level of rockfall hazard on three sites using a qualitative and a quantitative method. A statistical analysis shows that there is a non-significant influence of the level of expertise.

Description: The role of EMODnet Chemistry in the European challenge for Good Environmental Status Matteo Vinci, Alessandra Giorgetti, and Marina Lipizer Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-226,2016 Manuscript under review for NHESS (discussion: open, 0 comments) EMODnet initiative aims to provide access to European marine data in an interoperable and free of restrictions way. The Chemistry lot focus on the fulfillment of EU MSFD and INSPIRE directives requirements to assess eutrophication and contaminants. It could play two main roles: provide standardized and quality checked buffers of data for specific Regions and act as an umbrella for standards, best practices and infrastructure to aggregate at Regional level the single member states.

Description: Drift simulation of MH370 debris using superensemble techniques Eric Jansen, Giovanni Coppini, and Nadia Pinardi Nat. Hazards Earth Syst. Sci., 16, 1623-1628, doi:10.5194/nhess-16-1623-2016, 2016 In March 2014, a commercial airliner vanished without a trace. The main wreckage of the plane was never recovered, except for some small parts that washed up more than 17 months after the disappearance. In this paper we show a method to model the most likely trajectories of floating debris from the aircraft. The results show that the assumed area of the crash site is compatible with the recovered debris and predict that further debris may be found along the African east coast.

Description: Construction and design defects in the residential buildings and observed earthquake damage types in Turkey Natural Hazards and Earth System Science, 15, 931-945, 2015 Author(s): M. T. Cogurcu Turkey is situated in a very active earthquake region. In the last century, several earthquakes resulted in thousands of deaths and enormous economic losses. In 1999, the Kocaeli earthquake had an approximate death toll of more than 20 000, and in 2011 the Van earthquake killed 604 people. In general, Turkish residential buildings have reinforced concrete structural systems. These reinforced concrete structures have several deficiencies, such as low concrete quality, non-seismic steel detailing and inappropriate structural systems including several architectural irregularities. In this study, the general characteristics of Turkish building stock and the deficiencies observed in structural systems are explained, and illustrative figures are given with reference to the Turkish Earthquake Code 2007. The poor concrete quality, lack of lateral or transverse reinforcement in beam–column joints and column confinement zones, high stirrup spacings, under-reinforced columns and over-reinforced beams are the primary causes of failures. Other deficiencies include weak-column–stronger-beam formations, insufficient seismic joint separations, soft-story or weak-story irregularities and short columns. Similar construction and design mistakes are also observed in other countries situated on active earthquake belts. Existing buildings still have these undesirable characteristics, and so to prepare for future earthquakes they must be rehabilitated.

Description: Assessing domestic water use habits for more effective water awareness campaigns during drought periods: a case study in Alicante, eastern Spain Natural Hazards and Earth System Science, 15, 963-972, 2015 Author(s): H. March, M. Hernández, and D. Saurí The design of water awareness campaigns could benefit from knowledge of the specific characteristics of domestic water use and the factors that may influence certain water consumption habits. This paper investigates water use in 450 households in 10 municipalities of drought-prone Alicante (Spain). We aim to increase knowledge about existing domestic water behaviors and therefore help to improve the design and implementation of future water awareness campaigns and even to consolidate reductions in water use after drought periods. The survey suggests that awareness campaigns should revise their scope and their channels of diffusion on a regular basis. In a more specific way, for the Alicante case we propose policy-oriented recommendations on the scope of action for further reductions.

Description: Interdependence and dynamics of essential services in an extensive risk context: a case study in Montserrat, West Indies Natural Hazards and Earth System Science, 15, 947-961, 2015 Author(s): V. L. Sword-Daniels, T. Rossetto, T. M. Wilson, and S. Sargeant The essential services that support urban living are complex and interdependent, and their disruption in disasters directly affects society. Yet there are few empirical studies to inform our understanding of the vulnerabilities and resilience of complex infrastructure systems in disasters. This research takes a systems thinking approach to explore the dynamic behaviour of a network of essential services, in the presence and absence of volcanic ashfall hazards in Montserrat, West Indies. Adopting a case study methodology and qualitative methods to gather empirical data, we centre the study on the healthcare system and its interconnected network of essential services. We identify different types of relationship between sectors and develop a new interdependence classification system for analysis. Relationships are further categorised by hazard conditions, for use in extensive risk contexts. During heightened volcanic activity, relationships between systems transform in both number and type: connections increase across the network by 41%, and adapt to increase cooperation and information sharing. Interconnections add capacities to the network, increasing the resilience of prioritised sectors. This in-depth and context-specific approach provides a new methodology for studying the dynamics of infrastructure interdependence in an extensive risk context, and can be adapted for use in other hazard contexts.

Description: Hail events across the Greater Metropolitan Severe Thunderstorm Warning Area Natural Hazards and Earth System Science, 15, 973-984, 2015 Author(s): A. A. Rasuly, K. K. W. Cheung, and B. McBurney This study addresses the recent climatology of hail occurrence in the Greater Metropolitan Severe Thunderstorm Warning Area (GMSTWA) of New South Wales (NSW). The study area is a sprawling suburban area with a population of nearly 4.7 million and one of Australia's largest metropoles. The main objective is to highlight the recent temporal–spatial fluctuations of hail event frequencies and magnitudes (sizes) for each of recognized and vastly inhabited local government areas (LGAs). The relevant hail event data from 1989 to 2013 were initially derived from the severe storm archive of the Australian Bureau of Meteorology. A climatologically oriented GIS technique was then applied in the examining and mapping procedure of all hail events and hail days reported throughout the study area. By applying a specific criterion, severe hail (defined as 2 cm or more in diameter) was cautiously selected for relevant analysis. The database includes 357 hail events with sizes 2–11 cm which occurred in 169 hail days (a day in which a hail event at least more than 2 cm reported) across the region during the past 25 years. The hail distribution patterns are neither temporally nor spatially uniform in magnitude throughout the study area. Temporal analysis indicated that most of hail events occur predominately in the afternoons with peak time of 1–5 p.m. Australian eastern standard time (EST). They are particularly common in spring and summer, reaching maximum frequency in November and December. There is an average of 14.3 events per year, but a significant decreasing trend in hail frequency and associated magnitude in the recent years has been identified. In turn, spatial analyses also established three main distribution patterns over the study area which include the Sydney metropolitan, the coastal and the most pronounced topographic effects. Based on the understanding of the favorable factors for thunderstorm development in the GMSTWA, the potential impacts from climate variability and future climate change have been briefly discussed.

Description: Accuracy of velocities from repeated GPS measurements Natural Hazards and Earth System Science, 15, 875-884, 2015 Author(s): V. Akarsu, D. U. Sanli, and E. Arslan Today repeated GPS measurements are still in use, because we cannot always employ GPS permanent stations due to a variety of limitations. One area of study that uses velocities/deformation rates from repeated GPS measurements is the monitoring of crustal motion. This paper discusses the quality of the velocities derived using repeated GPS measurements for the aim of monitoring crustal motion. From a global network of International GNSS Service (IGS) stations, we processed GPS measurements repeated monthly and annually spanning nearly 15 years and estimated GPS velocities for GPS baseline components latitude, longitude and ellipsoidal height. We used web-based GIPSY for the processing. Assuming true deformation rates can only be determined from the solutions of 24 h observation sessions, we evaluated the accuracy of the deformation rates from 8 and 12 h sessions. We used statistical hypothesis testing to assess the velocities derived from short observation sessions. In addition, as an alternative control method we checked the accuracy of GPS solutions from short observation sessions against those of 24 h sessions referring to statistical criteria that measure the accuracy of regression models. Results indicate that the velocities of the vertical component are completely affected when repeated GPS measurements are used. The results also reveal that only about 30% of the 8 h solutions and about 40% of 12 h solutions for the horizontal coordinates are acceptable for velocity estimation. The situation is much worse for the vertical component in which none of the solutions from campaign measurements are acceptable for obtaining reliable deformation rates.

Description: Levee reliability analyses for various flood return periods – a case study in southern Taiwan Natural Hazards and Earth System Science, 15, 919-930, 2015 Author(s): W.-C. Huang, H.-W. Yu, and M.-C. Weng In recent years, heavy rainfall conditions have caused disasters around the world. To prevent losses by floods, levees have often been constructed in inundation-prone areas. This study performed reliability analyses for the Chiuliao First Levee in southern Taiwan. The failure-related parameters were the water level, the scouring depth, and the in situ friction angle. Three major failure mechanisms were considered: the slope sliding failure of the levee and the sliding and overturning failures of the retaining wall. When the variability of the in situ friction angle and the scouring depth are considered for various flood return periods, the variations of the factor of safety for the different failure mechanisms show that the retaining wall sliding and overturning failures are more sensitive to the change of the friction angle. When the flood return period is greater than 2 years, the levee could fail with slope sliding for all values of the water level difference. The results of levee stability analysis considering the variability of different parameters could aid engineers in designing the levee cross sections, especially with potential failure mechanisms in mind.

Description: Monitoring and prediction in early warning systems for rapid mass movements Natural Hazards and Earth System Science, 15, 905-917, 2015 Author(s): M. Stähli, M. Sättele, C. Huggel, B. W. McArdell, P. Lehmann, A. Van Herwijnen, A. Berne, M. Schleiss, A. Ferrari, A. Kos, D. Or, and S. M. Springman Rapid mass movements (RMM) pose a substantial risk to people and infrastructure. Reliable and cost-efficient measures have to be taken to reduce this risk. One of these measures includes establishing and advancing the state of practice in the application of early warning systems (EWSs). EWSs have been developed during the past decades and are rapidly increasing. In this paper, we focus on the technical part of EWSs, i.e., the prediction and timely recognition of imminent hazards, as well as on monitoring slopes at risk and released mass movements. Recent innovations in assessing spatial precipitation, monitoring and precursors of the triggering and deformation of RMM offer new opportunities for next-generation EWSs. However, technical advancement can only be transferred into more reliable, operational EWSs with an adequate well-instructed dedicated staff. To this end, an intense dialog between scientists, engineers and those in charge of warning, as well as further experience with new comprehensive prototype systems jointly operated by scientists and practitioners, will be essential.

Description: Flood warnings in coastal areas: how do experience and information influence responses to alert services? Natural Hazards and Earth System Science, 15, 703-714, 2015 Author(s): G. Pescaroli and M. Magni Many studies discuss the economic and technical aspects of flood warnings. Less attention has been given to the social and behavioural patterns that affect alert services. In particular, the literature focuses on warnings activated in river basins or marine environments without providing clear evidence on Mediterranean coastal areas, even though these are subjected to growing flood risk related to climate change. This paper is a first attempt to bridge this gap. Our research develops an in-depth analysis of the village of Cesenatico on the Adriatic Sea coast. Here the municipality adopted two complementary warning systems: a siren and an alert via short message service (SMS). The analysis focuses on a survey conducted in 2011 and 2012 with 228 participants. The relationships between social and behavioural variables and warning services are investigated as well as flood preparedness and information dissemination. Qualitative evidence from informal interviews is used to support the understanding of key responses. The conclusions show how different social and behavioural patterns can influence the effectiveness and use of warning systems, regardless of the technology adopted and the structural mitigation measures implemented. Education, training and accountability are seen to be critical elements for implementation. Finally, the statistical output is used to suggest new questions and new directions for research.

Description: Corrigendum to "Wind waves in the Black Sea: results of a hindcast study" published in Nat. Hazards Earth Syst. Sci., 14, 2883–2897, 2014 Natural Hazards and Earth System Science, 15, 767-767, 2015 Author(s): V. S. Arkhipkin, F. N. Gippius, K. P. Koltermann, and G. V. Surkova No abstract available.

Description: Comparison of storm damage functions and their performance Natural Hazards and Earth System Science, 15, 769-788, 2015 Author(s): B. F. Prahl, D. Rybski, O. Burghoff, and J. P. Kropp Winter storms are the most costly natural hazard for European residential property. We compare four distinct storm damage functions with respect to their forecast accuracy and variability, with particular regard to the most severe winter storms. The analysis focuses on daily loss estimates under differing spatial aggregation, ranging from district to country level. We discuss the broad and heavily skewed distribution of insured losses posing difficulties for both the calibration and the evaluation of damage functions. From theoretical considerations, we provide a synthesis between the frequently discussed cubic wind–damage relationship and recent studies that report much steeper damage functions for European winter storms. The performance of the storm loss models is evaluated for two sources of wind gust data, direct observations by the German Weather Service and ERA-Interim reanalysis data. While the choice of gust data has little impact on the evaluation of German storm loss, spatially resolved coefficients of variation reveal dependence between model and data choice. The comparison shows that the probabilistic models by Heneka et al. (2006) and Prahl et al. (2012) both provide accurate loss predictions for moderate to extreme losses, with generally small coefficients of variation. We favour the latter model in terms of model applicability. Application of the versatile deterministic model by Klawa and Ulbrich (2003) should be restricted to extreme loss, for which it shows the least bias and errors comparable to the probabilistic model by Prahl et al. (2012).

Description: Spatial-Temporal Clustering of Tornadoes Bruce D. Malamud and Donald L. Turcotte Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-71,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We introduce a novel method for the spatio-temporal cluster analysis of severe tornado touchdowns that are part of tornado outbreaks. Tornado outbreaks, groups of tornadoes that occur close to each other temporally and spatially, constitute a severe hazard that have few quantitative measures. Our new approach, which we illustrate using two severe tornado outbreaks from 2011, differentiates between types of tornado outbreaks, and within outbreaks, identification of clusters in both time & space.

Description: A coupled wave-3D hydrodynamics model of the Taranto Sea (Italy): a multiple-nesting approach Maria Gabriella Gaeta, Achilleas G. Samaras, Ivan Federico, and Renata Archetti Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-95,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The present work describes an operational strategy for the development of a multiscale modelling system, based on a multiple–nesting approach and open–source numerical models. The strategy was applied and validated for the Gulf of Taranto in South Italy, scaling large–scale oceanographic model results to high–resolution coupled wave–3D hydrodynamics simulations for the area of Mar Grande in Taranto Sea. The spatial and temporal high – resolution simulations were performed using the open–source.

Description: Lightning and electrical activity during the Shiveluch volcano eruption on 16 November 2014 Boris M. Shevtsov, Pavel P. Firstov, Nina V. Cherneva, Robert H. Holzworth, and Renat R. Akbashev Nat. Hazards Earth Syst. Sci., 16, 871-874, doi:10.5194/nhess-16-871-2016, 2016 The Kamchatka volcano group is located near populated areas and international air routes. Due to this, explosive eruptions are a serious threat to their security. To decrease the risks, effective systems for remote detection of eruptions are necessary. WWLLN resolution is enough for the remote sensing of the volcano lightning activity in the early stage of ash cloud formation a few minutes after the eruption when electrification proceeds the most intensively.

Description: Flood forecasting using transboundary data with the fuzzy inference system: The Maritza (Meriç) River Abdurrahim Aydın, İbrahim Yücedağ, and Remzi Eker Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-86,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Because the section of the Maritza River inside the Turkish border is short, there is not adequate warning time for Turkey to alert the population against flash floods. Although early warning systems offer the population time to evacuate before floods, improving such systems involves multiple components, each with a cost. That's why, four fuzzy models were developed satisfactorily predict the flow regime with high accuracy from transboundary flow data originating from three gauging stations.

Description: The observed clustering of damaging extratropical cyclones in Europe Stephen Cusack Nat. Hazards Earth Syst. Sci., 16, 901-913, doi:10.5194/nhess-16-901-2016, 2016 Clusters of severe windstorms threaten solvency in the (re-)insurance industry. Risk management is made highly uncertain due to so few clusters of severe storms in the past few decades. This research brought together a wide variety of historical storm damage information spanning the past few centuries in Europe to increase our knowledge of clustering of damaging storms. Clustering was found to increase with more severe storms, with weaker signs of more clustering off the main storm track.

Description: Evaluation of the Search and Rescue Leeway model into the Tyrrhenian sea: a new point of view Antonia Di Maio, Mathew Vayalumkal Martin, and Roberto Sorgente Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-109,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The trajectories prediction of the floating objects above the sea surface represents an important task in the search and rescue (SAR) operations. In this paper we show how may be possible estimate the most probable search area by means of a stocastic model, schematizing appropriately the shape of the object and evaluating the forces acting on it. The LEEWAY model, a Montecarlo-based ensemble trajectory model, has been used; here not only the statistical law to calculate the leeway is employed but also an almost deterministic law inspired by the boundary layer theory. The model is nested with the sub-regional hydrodynamic model TSCRM (Thyrrenian Sicily Channel Regional Model) developed in the framework of PON-TESSA (National Operative Programs-TEchnology for the Situational Sea Awareness) project. The principal objective of the work is to validate the new approach of leeway calculation relying on a real event of Person in Water (PIW), occurred on July 2013 in the Thyrrenian Sea. The results show that assimilating a human body to a cylinder and estimating either the transition from laminar to turbulent boundary layer and the drag coefficients, may be possible to solve a forces balance equation which permits to estimate with good approximation the search area. This new point of view leads to the possibility to check the same approach also on other different categories of targets, so as to overcome in the future the limitations associated with calculation of leeway by means of the standard statistical law.

Description: Assessing the risk posed by natural hazards to infrastructures Unni Marie Kolderup Eidsvig, Krister Kristensen, and Bjørn Vidar Vangelsten Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-89,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This paper proposes a model for assessing the risk posed by natural hazards to infrastructures. The model prescribes a three level analysis with increasing level of detail, moving from qualitative to quantitative analysis. The focus is on a methodology for semi-quantitative analysis to be performed at the second level. The purpose of this type of analysis is to perform a screening of the scenarios of natural hazards threatening the infrastructures, identifying the most critical scenarios and investigating the need for further analyses (third level). The proposed semi-quantitative methodology considers the frequency of the natural hazard, different aspects of vulnerability including the physical vulnerability of the infrastructure itself and the societal dependency on the infrastructure. An indicator-based approach is applied, ranking the indicators on a relative scale according to pre-defined ranking criteria. The proposed indicators, which characterize conditions that influence the probability of an infrastructure break-down caused by a natural event, are defined as 1) Robustness and buffer capacity, 2) Level of protection, 3) Quality/Level of maintenance and renewal, 4) Adaptability and quality in operational procedures and 5) Transparency/complexity/degree of coupling. Further indicators describe the societal consequences of the infrastructure failure, such as Redundancy and/or substitution, Restoration effort/duration, Preparedness, early warning and emergency response and Dependencies and cascading effects. The aggregated risk estimate is a combination of the semi-quantitative vulnerability indicators, as well as quantitative estimates of the frequency of the natural hazard, the potential duration of the infrastructure malfunctioning (depending e.g. on the required restoration effort) and the number of users of the infrastructure. Case studies for two Norwegian municipalities are presented where risk posed by adverse weather and natural hazards to primary road, water supply and power network is assessed. The application examples show that the proposed model provides a useful tool for screening of potential undesirable events, contributing to a targeted reduction of the risk.

Description: Debris flow impact estimation on a rigid barrier Federico Vagnon and Andrea Segalini Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-80,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This study has the aim of reviewing the dynamics of debris flow impact against rigid structures and providing a new simple formulation to predict peak thrust. The equation proposed differs from other formulations because takes into account both flow characteristics and material properties and barrier dimensions. The model developed has a good capability to predict force measured during the laboratory tests.

Description: Local and regional smoke impacts from prescribed fires Owen F. Price, Bronwyn Horsey, and Ningbo Jiang Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-66,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We measured particulate levels at distances ranging from 50 m–20 km from two prescribed fires and compared the values to those predicted from an atmospheric dispersion model. The model performed well during the day but not for areas close to the fire (under 1 km) which experienced high pollution peaks and did not predict night-time pollution in one of the fires over an area of 120,000 hectares caused by a temperature inversion.

Description: Regional prioritisation of flood risk in mountainous areas María Carolina Rogelis, Micha Werner, Nelson Obregón, and Nigel Wright Nat. Hazards Earth Syst. Sci., 16, 833-853, doi:10.5194/nhess-16-833-2016, 2016 A method to identify mountainous watersheds with the highest flood risk at the regional level is proposed and applied in Bogotá (Colombia). Vulnerability at the regional level was assessed and combined with an existing flood susceptibility indicator, thus providing an index that allows the watersheds to be prioritised. Results show that vulnerability can be expressed in terms of four constituent indicators and a sensitivity analysis shows that the classification of vulnerability is robust.

Description: Patterns and trends of high-impact weather in China during 1959–2014 Jun Shi, Kangmin Wen, and Linli Cui Nat. Hazards Earth Syst. Sci., 16, 855-869, doi:10.5194/nhess-16-855-2016, 2016 The spatial and temporal characteristics of the frequencies of four types of high-impact weather (HIW), i.e. snowfall, thunderstorms, fog and hailstorms, were analysed in China during 1959–2014. Results indicate a significant decrease in the number of snowfall days, thunderstorm days and thunderstorm spells in all six regions of China, with regional decreasing rates of 0.1–3.4 days, 1.6–5.1 days and 0.23–0.77 times per decade respectively. The number of foggy days, hailstorm days and snowfall spells decreased at rates of 0.2–1.8 days, 0.1–0.7 days and 0.14–0.44 times per decade respectively in almost all regions and fog and hailstorm spells decreased at rates of 0.06–0.17 and 0.001–0.043 times per decade respectively in most regions of China. Spatially, there was more snowfall in northeastern China and western China, and more thunderstorms in southern China and southwestern China. The number of fog events was larger in some high mountain stations, eastern China and central China. Hailstorms were concentrated on Qinghai–Tibet Plateau. Over the past 56 years, snowfall days, thunderstorm days and thunderstorm spells decreased in most parts of China, and hailstorm days decreased in northeastern China, most parts of northern China and Tibet, southern Qinghai and western Sichuan. The spatial trends of foggy days, foggy spells, snowfall spells and hailstorm spells were not significant in most parts of China. With global warming, some types of HIW are likely to increase in their intensities, so more mitigation and adaptation strategies are still essential for local government and the public in China.

Description: Maintenance and risk management of rockfall protection net fences through numerical study of deteriorations Andrea Luciani, Monica Barbero, Daniele Martinelli, and Daniele Peila Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-78,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Maintenance of rockfall protection net fences is fundamental for public administrations in order to guarantee risk mitigation. In this paper the influence of deteriorations on the behaviour of this works is analysed using a numerical simulation of the impact of rocks on net fences with different damages. The residual efficiency of a deteriorated net fence is extimated and the resulting variation of the risk mitigation is evaluated. This appraisal allows owners to better plan maintenance works.

Description: A quick earthquake disaster loss assessment method supported by dasymetric data for emergency response in China Jinghai Xu, Jiwen An, and Gaozong Nie Nat. Hazards Earth Syst. Sci., 16, 885-899, doi:10.5194/nhess-16-885-2016, 2016 The core contribution of this study is a new earthquake disaster loss estimation method for earthquake emergency response based on dasymetric exposure data, which consists of two phases: a pre-earthquake phase and a co-earthquake phase. This method can not only improve the speed and accuracy of earthquake disaster estimation for co-earthquake response, but it also provides the spatial distribution of possible deaths and building damage.

Description: Hazard mapping related to structurally controlled landslides in Southern Leyte, Philippines Paul Kenneth Luzon, Kristina Montalbo, Jam Galang, Jasmine May Sabado, Carmille Marie Escape, Raquel Felix, and Alfredo Mahar Francisco Lagmay Nat. Hazards Earth Syst. Sci., 16, 875-883, doi:10.5194/nhess-16-875-2016, 2016 To investigate the present-day morphology of the 2006 Guinsaugon landslide scar and potential failure that may occur, analysis of a 5 m resolution IfSAR-derived DTM was conducted using Coltop3D and Matterocking software to produce a structurally controlled landslide hazard map for Southern Leyte, Philippines. This type of simulated hazard maps would be useful for disaster prevention and to facilitate disaster risk reduction efforts for landslide-susceptible areas in the country.

Description: 〈b〉Wave run-up prediction and observation in a micro-tidal beach〈/b〉〈br〉 Diana Di Luccio, Guido Benassai, Giorgio Budillon, Luigi Mucerino, Raffaele Montella, and Eugenio Pugliese Carratelli〈br〉 Nat. Hazards Earth Syst. Sci., 18, 2841-2857, https://doi.org/10.5194/nhess-18-2841-2018, 2018〈br〉 Forecasting and hindcasting the action of sea storms on piers, coastal structures and beaches is important to mitigate their effects. To this end, with particular regard to low coasts and beaches, we have configured a computational model chain based partly on open-access models and partly on an ad-hoc-developed numerical calculator to evaluate beach wave run-up levels. The results were validated by a set of specially conceived video-camera-based experiments on a micro-tidal beach.

Description: 〈b〉Estimation of soil erosion considering soil loss tolerance in karst area〈/b〉〈br〉 Yue Cao, Shijie Wang, Xiaoyong Bai, Huiwen Li, Cheng Zeng, Yichao Tian, Fei Chen, Luhua Wu, and Mingming Wang〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-310,2018〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 Due to the soil holding capacity is very limited in karst area, it is necessary to consider the allowable loss of soil. Here we took thermodynamic dissolution model of carbonate rocks and the lithological characteristics to estimate soil loss tolerance, then corrected and quantitatively evaluated the soil erosion. We identified the spatial pattern of soil loss tolerance in karst area, found RUSLE overestimated soil erosion in karst area and proposed an idea for evaluating soil erosion in karst.

Description: 〈b〉InSAR Technique Applied to the Monitoring of the Qinghai-Tibet Railway〈/b〉〈br〉 Qingyun Zhang, Yongsheng Li, Jingfa Zhang, and Yi Luo〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-287,2018〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 Before the opening of the railway, the deformation of Qinghai-Tibet Railway was very small and considered stable. After opening, the overall stability of the railway section was good. The main deformation areas are concentrated in the areas where railway lines turn and geological disasters are concentrated. In order to ensure the safety of railway operation, it is necessary to carry out long-term time series observation along the Qinghai-Tibet Railway.

Description: 〈b〉High-spatial resolution probability maps of drought duration and magnitude across Spain〈/b〉〈br〉 Fernando Domínguez-Castro, Sergio M. Vicente-Serrano, Miquel Tomás-Burguera, Marina Peña-Gallardo, Santiago Beguería, Ahmed El Kenawy, Yolanda Luna, and Ana Morata〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-289,2018〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 We mapped – for the first time – the probability of occurrence of drought over Spain, with the overriding aim of improving current drought assessment, management and mitigation measures and strategies across the region. Spatially, our estimations suggest a higher probability of extreme drought events in southern and central areas of Spain, compared to northern and eastern regions. Nevertheless, there are strong differences between drought indices, as well as among drought timescales.

Description: 〈b〉Stochastic downscaling of precipitation in complex orography: a simple method to reproduce a realistic fine-scale climatology〈/b〉〈br〉 Silvia Terzago, Elisa Palazzi, and Jost von Hardenberg〈br〉 Nat. Hazards Earth Syst. Sci., 18, 2825-2840, https://doi.org/10.5194/nhess-18-2825-2018, 2018〈br〉 This study proposes a modification to a stochastic downscaling method for precipitation, RainFARM, to improve the representation of the statistics of the daily precipitation at fine scales (1 km) in mountain areas. This method has been demonstrated in the Alps and it has been found to reconstruct small-scale precipitation distribution. It can be employed in a number of applications, including the analysis of extreme events and their statistics and hydrometeorological hazards.

Description: 〈b〉Statistical theory of probabilistic hazard maps: a probability distribution for the hazard boundary location〈/b〉〈br〉 David M. Hyman, Andrea Bevilacqua, and Marcus I. Bursik〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-344,2018〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 In this work, we present new methods for calculating the mean, standard deviation, median, and modal locations of the boundaries of volcanic hazards. These calculations are based on a new, mathematically rigorous definition of a probabilistic hazard map – a way to map the probabilities of inundation by a given hazard. We apply this analysis to several models of volcanic flows: simple models of viscous flows, complex models of a tabletop granular flow, and a complex model of a volcanic mud flow.

Description: 〈b〉On the use of weather regimes to forecast meteorological drought over Europe〈/b〉〈br〉 Christophe Lavaysse, Jürgen Vogt, Andrea Toreti, Marco L. Carrera, and Florian Pappenberger〈br〉 Nat. Hazards Earth Syst. Sci., 18, 3297-3309, https://doi.org/10.5194/nhess-18-3297-2018, 2018〈br〉 Forecasting droughts in Europe 1 month in advance would provide valuable information for decision makers. However, these extreme events are still difficult to predict. In this study, we develop forecasts based on predictors using the geopotential anomalies, generally more predictable than precipitation, derived from the ECMWF model. Results show that this approach outperforms the prediction using precipitation, especially in winter and in northern Europe, where 65 % of droughts are predicted.

Description: 〈b〉Loss assessment of building and content damages from potential earthquake risk in Seoul, Korea〈/b〉〈br〉 Wooil Choi, Jae-Woo Park, and Jinhwan Kim〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-281,2018〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 In recent years, earthquakes have been occurring in Korea where no earthquakes occurred in the past.It is needed that appropriate response planning using simulations in countries with less earthquake risk management experiences. especially important to evaluate earthquake damage financially. This paper is a model study for urban earthquake risk management and it is meaningful to generate basis data of cost benefit analysis of disaster prevention plan by financial evaluation of earthquake damage.

Description: 〈b〉Numerical and remote techniques for operational beach management under storm group forcing〈/b〉〈br〉 Verónica Morales-Márquez, Alejandro Orfila, Gonzalo Simarro, Lluís Gómez-Pujol, Amaya Álvarez-Ellacuría, Daniel Conti, Álvaro Galán, Andrés F. Osorio, and Marta Marcos〈br〉 Nat. Hazards Earth Syst. Sci., 18, 3211-3223, https://doi.org/10.5194/nhess-18-3211-2018, 2018〈br〉 This work analyzes the response of a beach under a series of storms using a numerical model, in situ measurements and video imaging. Time recovery after storms is a key issue for local beach managers, who are pressed by tourism stakeholders to nourish the beach after energetic processes in order to reach the quality standards required by beach users.

Description: 〈b〉Preface: Landslide early warning systems: monitoring systems, rainfall thresholds, warning models, performance evaluation and risk perception〈/b〉〈br〉 Samuele Segoni, Luca Piciullo, and Stefano Luigi Gariano〈br〉 Nat. Hazards Earth Syst. Sci., 18, 3179-3186, https://doi.org/10.5194/nhess-18-3179-2018, 2018〈br〉

Description: 〈b〉Towards a comprehensive view of dust events from multiple satellite and ground measurements: exemplified by the May 2017 East Asian dust storm〈/b〉〈br〉 Lu She, Yong Xue, Jie Guang, Yahui Che, Cheng Fan, Ying Li, and Yanqing Xie〈br〉 Nat. Hazards Earth Syst. Sci., 18, 3187-3201, https://doi.org/10.5194/nhess-18-3187-2018, 2018〈br〉 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 a 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.