bluuebunny/crossref_metadata_2025 huggingface dataset:
Calendaricities and multimodality in the Eastern Mediterranean cyclonic activity
Authors: Osetinsky I. , Alpert P.
Published: April 2010

Abstract. Calendaricities, or the occurrence of weather anomalies on fixed calendar dates, are investigated for the Eastern Mediterranean (EM). The anomalies discussed here are the maxima and minima in the frequency of occurrence of the EM synoptic systems bearing rainfall. Those are mostly the Winter Lows passing over Cyprus en route eastward of the Ionian Sea where they are generated in situ or come to from N. Italy. The Winter Lows produce the rainfall over the central and northern EM areas, including Cyprus, Israel, Lebanon, NW Syria, W. Jordan. The southern EM areas, i.e. S. Israel and NE Egypt, get rainfall followed by floods due to the Winter Lows as well, and in addition, due to a small proportion of the mostly dry Red Sea Troughs that occasionally turn out to cause heavy rainfall. The analysis of the daily resolved data based on the NCEP/NCAR reanalysis is carried out. A comparison of two 28-yr periods, 1948–1975 and 1976–2003, different in global climatology, showed their similarity in the timing of peaks in EM cyclonic activity. The winter was found to have five maxima of cyclonic activity, centered on early February and nearly bell-shaped over their magnitudes. This supports the earlier hypotheses of multimodality in the EM rainfall. The Red Sea Troughs have their main peak of occurrence in the late October – early November, and their small rain-bearing proportion falls as well on this period of a year.
Data management and GIS in the Center for Disaster Management and Risk Reduction Technology (CEDIM): from integrated spatial data to the mapping of risk
Authors: Köhler P. , Müller M. , Sanders M. , Wächter J.
Published: April 2010

Abstract. The project "Risk Map Germany" of the Center for Disaster Management and Risk Reduction Technology (CEDIM) aims at the examination of existing and the development of new approaches for integrated risk assessment as well as the realisation of risk analyses for selected threats and regions. Hazard, vulnerability and risk maps display the results and provide valuable information for planning, insurances, emergency management, science and the public. This article describes the development of the basic information infrastructure for CEDIM and the "Risk Map Germany" providing components for the networking of participating institutions, for common data management, data dissemination and publication. While a web based project platform offers information and communication facilities for all the project members and also the presentation of CEDIM to the public, an integrated data base is prepared as foundation for cross-discipline but common risk assessment. It is made available by the spatial data service "CEDIM Data Center" which allows the project members to inform themselves about the characteristics of existing data and its applicability for their specific tasks by exploring GIS functionalities. Suitable data can be downloaded and further processed in their own work environment. The components' alignment with the principles of Spatial Data Infrastructures is required to accomplish the suppositions for long-term availability and accessibility of data, information and services.
CEDIM Risk Explorer – a map server solution in the project "Risk Map Germany"
Authors: Müller M. , Vorogushyn S. , Maier P. , Thieken A. H. , Petrow T. , Kron A. , Büchele B. , Wächter J.
Published: April 2010

Abstract. The project "Risk Map Germany" at the Center for Disaster Management and Risk Reduction Technology (CEDIM) aims at visualizing hazards, vulnerabilities and risks associated with natural and man made hazards. CEDIM as an interdisciplinary project unified various expertise like earthquake, storm and flood disaster research. Our aim was to visualize the manifold data exploration in thematic maps. The implemented Web-GIS solution "CEDIM Risk Explorer" represents the map visualizations of the different risk research. This Web-GIS integrates results from interdisciplinary work as maps of hazard, vulnerability and risk in one application and offers therefore new cognitions to the user by enabling visual comparisons. The present paper starts with a project introduction and a literature review of distributed GIS environments. Further the methods of map realization and visualization in the selected technical solution is worked out. Finally, the conclusions give the perspectives for future developments to the "CEDIM Risk Explorer".
A case study carried out with two different NWP systems
Authors: Kållberg P. , Montani A.
Published: April 2010

Abstract. A model intercomparison between two atmospheric models, the non–hydrostatic Lokal Modell (LM) and the hydrostatic HIgh Resolution Limited Area Model (HIRLAM) is carried out for a one-week period, including a case of cyclogeneis leading to heavy precipitation over Northern Italy. The two models, very different in terms of data-assimilation and numerics, provide different results in terms of forecasts of surface fields. Opposite diurnal biases for the two models are found in terms of screen level temperatures. HIRLAM wind speed forecasts are too strong, while LM precipitation forecasts have larger extremes. The intercomparison exercise identifies some systematic differences in the weather products generated by the two systems and sheds some light on the biases of the two numerical weather prediction systems.
Development of a methodology to assess man-made risks in Germany
Authors: Borst D. , Jung D. , Murshed S. M. , Werner U.
Published: April 2010

Abstract. Risk is a concept used to describe future potential outcomes of certain actions or events. Within the project "CEDIM – Risk Map Germany – Man-made Hazards" it is intended to develop methods for assessing and mapping the risk due to different human-induced hazards. This is a task that has not been successfully performed for Germany so far. Concepts of catastrophe modelling are employed including the spatial modelling of hazard, the compilation of different kinds of exposed elements, the estimation of their vulnerability and the direct loss potential in terms of human life and health. The paper is divided in two sections: First, an analytic framework for assessing the broad spectrum of human-induced risks is introduced. This approach is then applied for three important types of human-induced hazards that are representative for a whole class of hazards: Accidents due to nuclear power plants (NPP) or air traffic, and terrorism. For the analysis of accidents, risk is measured with respect to getting injured or dying when living in certain buffer zones around hazard locations. NPP hazard expert knowledge is used and supplemented with observations on aging effects leading to a proprietary index value for the risk. Air traffic risk is modelled as an area related phenomenon based on available accident statistics leading to an expected value of risk. Terrorism risk is assessed by the attraction certain elements (like embassies in the case of conventional threats) display in the eye of potential aggressors. For non-conventional targets like football games, a detailed approach measuring their susceptibility to different kinds of attacks within predefined scenarios was developed; this also allows a ranking of attack modes.
Sediment transport and deposition during extreme sea storm events at the Salerno Bay (Tyrrhenian Sea): comparison of field data with numerical model results
Authors: Budillon F. , Vicinanza D. , Ferrante V. , Iorio M.
Published: April 2010

Abstract. Seismic stratigraphy and core litho-stratigraphy in the Salerno Bay inner shelf (Southern Tyrrhenian Sea) reveal significant storm deposition episodes over the last 1 ky. Three major events are preserved as decimetre thick silt/sand layers bounded at their base by erosional surfaces and sealed in the muddy marine sequences between 25 and 60 m of depth. Geochronology and chrono-stratigraphy on core sediment point towards a recurrence of major sea storms between 0.1 and 0.3 ky and put the last significant event in the 19th century, when no local meteorological time series is available. A modelling of extreme sea-storms with a return period of about 0.1 ky is here proposed based on historical hindcast and aims at explaining the occurrence of such unusual deep and thick sand deposits in the northern sector of the bay. Results highlight the vulnerability of the northern coast of the Salerno Bay to the south western sea storms which can drive waves up to about 8 m high and wave period of about 13 s. With these conditions an intense combined flow current is formed and might account for winnowing fine sand down to the depth of 40 m at least. The numerical model thus confirms a possible sand transport in the bottom boundary layer due to wave-current interaction and could corroborate the interpretation of the most recent sand layers, included in the cores, as being generated under extreme sea storm conditions.
Probabilistic seismic hazard map for Bulgaria as a basis for a new building code
Authors: Simeonova S. D. , Solakov D. E. , Leydecker G. , Busche H. , Schmitt T. , Kaiser D.
Published: April 2010

Abstract. A seismic hazard map proposed as part of a new building code for Bulgaria is presented here on basis of the recommendations in EUROCODE 8. Seismic source zones within an area of about 200 km around Bulgaria were constructed considering seismicity, neotectonic and geological development. The most time consuming work was to establish a homogeneous earthquake catalogue out of different catalogues. The probabilistic seismic hazard assessment in terms of intensities is performed following Cornell (1968) with the program EQRISK (see McGuire, 1976), modified by us for use of intensities. To cope with the irregular isoseismals of the Vrancea intermediate depth earthquakes a special attenuation factor is introduced (Ardeleanu et al., 2005), using detailed macroseismic maps of three major earthquakes. The final seismic hazard is the combination of both contributions, of zones with crustal earthquakes and of the Vrancea intermediate depth earthquakes zone. Calculations are done for recurrence periods of 95, 475 and 10 000 years.
The East Aegean Sea strong earthquake sequence of October–November 2005: lessons learned for earthquake prediction from foreshocks
Authors: Papadopoulos G. A. , Latoussakis I. , Daskalaki E. , Diakogianni G. , Fokaefs A. , Kolligri M. , Liadopoulou K. , Orfanogiannaki K. , Pirentis A.
Published: April 2010

Abstract. The seismic sequence of October–November 2005 in the Samos area, East Aegean Sea, was studied with the aim to show how it is possible to establish criteria for (a) the rapid recognition of both the ongoing foreshock activity and the mainshock, and (b) the rapid discrimination between the foreshock and aftershock phases of activity. It has been shown that before the mainshock of 20 October 2005, foreshock activity is not recognizable in the standard earthquake catalogue. However, a detailed examination of the records in the SMG station, which is the closest to the activated area, revealed that hundreds of small shocks not listed in the standard catalogue were recorded in the time interval from 12 October 2005 up to 21 November 2005. The production of reliable relations between seismic signal duration and duration magnitude for earthquakes included in the standard catalogue, made it possible to use signal durations in SMG records and to determine duration magnitudes for 2054 small shocks not included in the standard catalogue. In this way a new catalogue with magnitude determination for 3027 events was obtained while the standard catalogue contains 1025 events. At least 55 of them occurred from 12 October 2005 up to the occurrence of the two strong foreshocks of 17 October 2005. This implies that foreshock activity developed a few days before the strong shocks of 17 October 2005 but it escaped recognition by the routine procedure of seismic analysis. The onset of the foreshock phase of activity is recognizable by the significant increase of the mean seismicity rate which increased exponentially with time. According to the least-squares approach the b-value of the magnitude-frequency relation dropped significantly during the foreshock activity with respect to the b-value prevailing in the declustered background seismicity. However, the maximum likelihood approach does not indicate such a drop of b. The b-value found for the aftershocks that followed the strong shock of 20 October 2005 is significantly higher than in foreshocks. The significant aftershock-foreshock difference in b-value is valid not only if the entire aftershock sequence is considered but also if only the segment of aftershocks that occurred within the first 24-h or the first 48-h after the mainshock of 20 October 2005 are taken into account. This difference in b-value should be examined further in other foreshock-aftershock sequences because it could be used as a diagnostic of the mainshock occurrence within a few hours after its generation.
Use of remote sensing and seismotectonic parameters for seismic hazard analysis of Bangalore
Authors: Sitharam T. G. , Anbazhagan P. , Ganesha Raj K.
Published: April 2010

Abstract. Deterministic Seismic Hazard Analysis (DSHA) for the Bangalore, India has been carried out by considering the past earthquakes, assumed subsurface fault rupture lengths and point source synthetic ground motion model. The sources have been identified using satellite remote sensing images and seismotectonic atlas map of India and relevant field studies. Maximum Credible Earthquake (MCE) has been determined by considering the regional seismotectonic activity in about 350 km radius around Bangalore. The seismotectonic map has been prepared by considering the faults, lineaments, shear zones in the area and past moderate earthquakes of more than 470 events having the moment magnitude of 3.5 and above. In addition, 1300 number of earthquake tremors having moment magnitude of less than 3.5 has been considered for the study. Shortest distance from the Bangalore to the different sources is measured and then Peak Horizontal Acceleration (PHA) is calculated for the different sources and moment magnitude of events using regional attenuation relation for peninsular India. Based on Wells and Coppersmith (1994) relationship, subsurface fault rupture length of about 3.8% of total length of the fault shown to be matching with past earthquake events in the area. To simulate synthetic ground motions, Boore (1983, 2003) SMSIM programs have been used and the PHA for the different locations is evaluated. From the above approaches, the PHA of 0.15 g was established. This value was obtained for a maximum credible earthquake having a moment magnitude of 5.1 for a source Mandya-Channapatna-Bangalore lineament. This particular source has been identified as a vulnerable source for Bangalore. From this study, it is very clear that Bangalore area can be described as seismically moderately active region. It is also recommended that southern part of Karnataka in particular Bangalore, Mandya and Kolar, need to be upgraded from current Indian Seismic Zone II to Seismic Zone III. Acceleration time history (ground motion) has been generated using synthetic earthquake model by considering the revised regional seismotectonic parameters. The rock level PHA map for Bangalore has been prepared and these maps are useful for the purpose of seismic microzonation, ground response analysis and design of important structures.
Hybrid Adaptive Filter development for the minimisation of transient fluctuations superimposed on electrotelluric field recordings mainly by magnetic storms
Authors: Konstantaras A. , Varley M. R. , Vallianatos F. , Makris J. P. , Collins G. , Holifield P.
Published: April 2010

Abstract. The method of Hybrid Adaptive Filtering (HAF) aims to recover the recorded electric field signals from anomalies of magnetotelluric origin induced mainly by magnetic storms. An adaptive filter incorporating neuro-fuzzy technology has been developed to remove any significant distortions from the equivalent magnetic field signal, as retrieved from the original electric field signal by reversing the magnetotelluric method. Testing with further unseen data verifies the reliability of the model and demonstrates the effectiveness of the HAF method.
Factors affecting seismic response of submarine slopes
Authors: Biscontin G. , Pestana J. M.
Published: April 2010

Abstract. The response of submerged slopes on the continental shelf to seismic or storm loading has become an important element in the risk assessment for offshore structures and "local" tsunami hazards worldwide. The geological profile of these slopes typically includes normally consolidated to lightly overconsolidated soft cohesive soils with layer thickness ranging from a few meters to hundreds of meters. The factor of safety obtained from pseudo-static analyses is not always a useful measure for evaluating the slope response, since values less than one do not necessarily imply slope failure with large movements of the soil mass. This paper addresses the relative importance of different factors affecting the response of submerged slopes during seismic loading. The analyses use a dynamic finite element code which includes a constitutive law describing the anisotropic stress-strain-strength behavior of normally consolidated to lightly overconsolidated clays. The model also incorporates anisotropic hardening to describe the effect of different shear strain and stress histories as well as bounding surface principles to provide realistic descriptions of the accumulation of the plastic strains and excess pore pressure during successive loading cycles. The paper presents results from parametric site response analyses on slope geometry and layering, soil material parameters, and input ground motion characteristics. The predicted maximum shear strains, permanent deformations, displacement time histories and maximum excess pore pressure development provide insight of slope performance during a seismic event.
Were freak waves involved in the sinking of the Tanker "Prestige"?
Authors: Lechuga A.
Published: April 2010

Abstract. This paper deals with the possible involvement of freak, rogue or giant waves in the damage suffered by the Tanker Prestige, which eventually led to its sinking. By reason of their very characteristics, giant waves are hard to record. Their more or less sudden appearance makes them fairly elusive objects, except for the consequences they produce. However, some hints with regard to the probability of their occurrence can be derived from considering how close the maritime weather of the area of interest is to the situation which is optimal for their generation. This paper takes into account the wave field in the area and at the time of the Prestige accident and investigates how near or how far the wave field was to the instability conditions that are favourable to the generation of freak waves in the different approximations. This paper explores mostly the modulation instability which is one of the most common mechanisms to produce freak waves: it leads to the decomposition of an initially homogeneous train of Stokes waves firstly into a series of groups of waves, whose envelope then produces the so-called "solitons", that then collapse in the form of a giant wave. This mechanism mainly occurs in deep waters. Zakharov studied it in 1968 and, independently, Benjamin and Feir analysed it in 1967. This paper proves that the wave field was conspicuously two dimensional with two main wave components travelling in directions almost orthogonal to each other. This means that the wave field was well outside the instability domain. Therefore it is concluded that freak waves were very unlikely generated and it is improbable that they were responsible for the accident.
3-D HOS simulations of extreme waves in open seas
Authors: Ducrozet G. , Bonnefoy F. , Le Touzé D. , Ferrant P.
Published: April 2010

Abstract. In the present paper we propose a method for studying extreme-wave appearance based on the Higher-Order Spectral (HOS) technique proposed by West et al. (1987) and Dommermuth and Yue (1987). The enhanced HOS model we use is presented and validated on test cases. Investigations of freak-wave events appearing within long-time evolutions of 2-D and 3-D wavefields in open seas are then realized, and the results are discussed. Such events are obtained in our periodic-domain HOS model by using different kinds of configurations: either i) we impose an initial 3-D directional spectrum with the phases adjusted so as to form a focused forced event after a while, or ii) we let 2-D and 3-D wavefields defined by a directional wave spectrum evolve up to the natural appearance of freak waves. Finally, we investigate the influence of directionality on extreme wave events with an original study of the 3-D shape of the detected freak waves.
On the influence of wind on extreme wave events
Authors: Touboul J.
Published: April 2010

Abstract. This work studies the impact of wind on extreme wave events, by means of numerical analysis. A High Order Spectral Method (HOSM) is used to generate freak, or rogue waves, on the basis of modulational instability. Wave fields considered here are chosen to be unstable to two kinds of perturbations. The evolution of components during the propagation of the wave fields is presented. Their evolution under the action of wind, modeled through Jeffreys' sheltering mechanism, is investigated and compared to the results without wind. It is found that wind sustains rogue waves. The perturbation most influenced by wind is not necessarily the most unstable.
A southeastern Mediterranean PV streamer and its role in December 2001 case with torrential rains in Israel
Authors: Krichak S. O. , Alpert P. , Dayan M.
Published: April 2010

Abstract. A precipitation event of unprecedented intensity took place over northern part of Israel during 4 December 2001–5 December 2001. The case was associated with formation of a Cyprus Low cyclone over the Asia Minor. In the current study the synoptic developments over the eastern part of the Mediterranean region are simulated with the MM5 nonhydrostatic model and analyzed based on dynamic tropopause patterns calculated from the simulation results. According to the results, a powerful potential vorticity (PV) streamer system played a major role in the process over the southeastern Mediterranean region. The PV streamer created conditions for seclusion of moist air masses from the equatorial East Africa and Atlantics during the cyclone development. Condensation of the moisture, associated with the latent heat release processes have contributed to the intense thunderstorm activity and heavy precipitation of the event.
Application of different signal analysis methods to the ULF data for the 1993 Guam earthquake
Authors: Ida Y. , Hayakawa M. , Timashev S.
Published: April 2010

Abstract. Two different analysis methods; (1) mono-fractal analysis (based on Higuchi method) and (2) flicker noise spectroscopy, have been applied to the same ULF (frequency less than 10 Hz) electromagnetic data observed at Guam during 3 years including the 1993 August Guam earthquake. The results by these two methods are found to be very consistent with each other; that is, some precursory effects seem to start about 3 months before the earthquake. This gives us a strong support to the self-organizing critical process before the Guam earthquake.
Towards an empirical vulnerability function for use in debris flow risk assessment
Authors: Fuchs S. , Heiss K. , Hübl J.
Published: April 2010

Abstract. In quantitative risk assessment, risk is expressed as a function of the hazard, the elements at risk and the vulnerability. From a natural sciences perspective, vulnerability is defined as the expected degree of loss for an element at risk as a consequence of a certain event. The resulting value is dependent on the impacting process intensity and the susceptibility of the elements at risk, and ranges from 0 (no damage) to 1 (complete destruction). With respect to debris flows, the concept of vulnerability – though widely acknowledged – did not result in any sound quantitative relationship between process intensities and vulnerability values so far, even if considerable loss occurred during recent years. To close this gap and establish this relationship, data from a well-documented debris flow event in the Austrian Alps was used to derive a quantitative vulnerability function applicable to buildings located on the fan of the torrent. The results suggest a second order polynomial function to fit best to the observed damage pattern. Vulnerability is highly dependent on the construction material used for exposed elements at risk. The buildings studied within the test site were constructed by using brick masonry and concrete, a typical design in post-1950s building craft in alpine countries. Consequently, the presented intensity-vulnerability relationship is applicable to this construction type within European mountains. However, a wider application of the presented method to additional test sites would allow for further improvement of the results and would support an enhanced standardisation of the vulnerability function.
Extreme value modelling of storm damage in Swedish forests
Authors: Bengtsson A. , Nilsson C.
Published: April 2010

Abstract. Forests cover about 56% of the land area in Sweden and forest damage due to strong winds has been a recurring problem. In this paper we analyse recorded storm damage in Swedish forests for the years 1965–2007. During the period 48 individual storm events with a total damage of 164 Mm³ have been reported with the severe storm on 8 to 9 January 2005, as the worst with 70 Mm³ damaged forest. For the analysis, storm damage data has been normalised to account for the increase in total forest volume over the period. We show that, within the framework of statistical extreme value theory, a Poisson point process model can be used to describe these storm damage events. Damage data supports a heavy-tailed distribution with great variability in damage for the worst storm events. According to the model, and in view of available data, the return period for a storm with damage in size of the severe storm of January 2005 is approximately 80 years, i.e. a storm with damage of this magnitude will happen, on average, once every eighty years. To investigate a possible temporal trend, models with time-dependent parameters have been analysed but give no conclusive evidence of an increasing trend in the normalised storm damage data for the period. Using a non-parametric approach with a kernel based local-likelihood method gives the same result.
Very Weak Signals (VWS) detected by stacking method according to different astronomical periodicities (HiCum)
Authors: van Ruymbeke M. , Zhu P. , Cadicheanu N. , Naslin S.
Published: April 2010

Abstract. A stacking method to detect very weak signals is introduced in this paper. This method is to stack observed data in different well known periodicities according to the astronomical clock since majority geophysical observations are time based. We validated this method by applying it in four different cases. Interactions behind the observed parameters become obviously after it is stacked in two diurnal and semidiurnal tidal periodical waves. Amplitude and phase variations will be also measurable when a sliding windows stacking is used. This could be an important reference to find precursors before some earthquakes and volcanic events, corresponding to attenuations of medium patterns.
On the electric field transient anomaly observed at the time of the Kythira M=6.9 earthquake on January 2006
Authors: Konstantaras A. , Makris J. P. , Vallianatos F. , Varley M. R.
Published: April 2010

Abstract. The study of the Earth's electromagnetic fields prior to the occurrence of strong seismic events has repeatedly revealed cases were transient anomalies, often deemed as possible earthquake precursors, were observed on electromagnetic field recordings of surface, atmosphere and near space carried out measurements. In an attempt to understand the nature of such signals several models have been proposed based upon the exhibited characteristics of the observed anomalies and different possible generation mechanisms, with electric earthquake precursors (EEP) appearing to be the main candidates for short-term earthquake precursors. This paper discusses the detection of a ULF electric field transient anomaly and its identification as a possible electric earthquake precursor accompanying the Kythira M=6.9 earthquake occurred on the 8 January 2006.
Evaluation of seismic effects on the landslide deposits of Monte Salta (Eastern Italian Alps) using distinct element method
Authors: Marcato G. , Fujisawa K. , Mantovani M. , Pasuto A. , Silvano S. , Tagliavini F. , Zabuski L.
Published: April 2010

Abstract. The aim of the paper is to present the modelling of the ground effects of seismic waves on a large debris deposit lying on a steep mountain slope, with particular attention paid to the potential triggering of slope movements. The study site is a mass of 2.5 million m3 rock fall deposit, named "Monte Salta Landslide", located on the northern slope of the Vajont valley, at the border between Veneto and Friuli Venezia Giulia regions in north-eastern Italy. Several historical landslide events were reported in the area in the past, first one dating back to the 17th century. The landslide deposit completely mantles the slope with a thick cover of rock blocks. The Mt. Salta landslide is conditioned by the presence of Mt. Borgà regional thrust, which uplifts Jurassic limestone on the top of Cretaceous rock units. Above the thrust zone, folded and highly fractured rock mass dips steeply towards the slope free face, producing highly unstable setting. The study area has been classified as high seismic hazard and different vulnerable elements can be affected by the remobilisation of debris, among which a village, a national road and a big quarry that was opened, with the intent to exploit the part of the landslide deposit for construction purposes. In this study, numerical analysis was performed, to simulate the slope behaviour using distinct element method and applying UDEC code. The 2-D models were built on three cross-sections and elasto-plastic behaviour was assumed, both for rock matrix and discontinuities. The earthquake effect was modelled in pseudo-dynamic way, i.e. by magnifying the acceleration and applying also its horizontal component. The expected seismic acceleration in the study area was calculated on the basis of previous studies as equal to 0.28 g. The results proved that the increase of the vertical component alone has a small influence on the deformational behaviour of the system. Hence, the acceleration vector was deviated at 5° and then at 10° from the vertical. A small increment of the displacement was observed in the first case, whereas very large movements occurred in the second. Therefore, it can be concluded that, besides the magnitude of the earthquake, even small seismic waves in horizontal direction could trigger significant movements and therefore hazardous conditions. The modelled scenario should be helpful for planning of the functional countermeasure works and civil defence evacuation plan.
Ultrasound monitoring of applied forcing, material ageing, and catastrophic yield of crustal structures
Authors: Gregori G. P. , Lupieri M. , Paparo G. , Poscolieri M. , Ventrice G. , Zanini A.
Published: April 2010

Abstract. A new kind of data analysis is discussed – and a few case histories of actual application are presented – concerning the physical information attainable by acoustic emission (AE) records in geodynamically active or volcanic areas. The previous analyses of such same kind of observations were reported in several papers appeared in the last few years, and here briefly recalled. They are concerned with the inference of the forcing ("F") acting on the physical system, and on the ageing ("T") or fatigue of its "solid" structures. The new analysis here discussed deals with the distinction between a state of applied stress ("hammer regime"), compared to state of "recovery regime" of the system while it seeks a new equilibrium state after having been perturbed. For instance, in the case of a seismic event – and according to some kind of almost intuitive argument – the "hammer regime" is the phenomenon leading to the main shock, while the "recovery regime" deals with the well known aftershocks. Such same intuitive inference, however, can be investigated by a much more formal algorithm, aimed at envisaging the minor changes of the behaviour of the system, during its history and during its present dynamic evolution. As a demonstrative application, detailed consideration is given of AE records – each one lasting for a few years – collected on the Italian peninsula vs. records collected on the Kefallinìa Island (western Greece). Such two areas are well known being characterised by some great comparative difference in their respective tectonic setting. When considering planetary scale phenomena, they appear comparatively very close to each other. Hence, they are likely being presumably affected by similar large-scale external actions, although they ought to be expected to respond in some completely different way. Such facts are clearly manifested by some substantially different AE responses of the local crustal structures. However, a full understanding of such entire set of geodynamic and tectonic details ought to require several year data series of AE records, and/or (maybe) also simultaneous AE records collected within some suitable array of AE stations. Such understanding ought to permit the inference of the spatial features of the crustal stress propagation – including its diagnosis and "forecasting" – in addition to the temporal diagnosis and "prevision" that can be attained by isolated point-like AE recording stations. Additional analyses are in progress.
Detection of metallic and plastic landmines using the GPR and 2-D resistivity techniques
Authors: Metwaly M.
Published: April 2010

Abstract. Low and non-metallic landmines are one of the most difficult subsurface targets to be detected using several geophysical techniques. Ground penetrating radar (GPR) performance at different field sites shows great success in detecting metallic landmines. However significant limitations are taking place in the case of low and non-metallic landmines. Electrical resistivity imaging (ERI) technique is tested to be an alternative or confirmation technique for detecting the metallic and non-metallic landmines in suspicious cleared areas. The electrical resistivity responses using forward modeling for metallic and non-metallic landmines buried in dry and wet environments utilizing the common electrode configurations have been achieved. Roughly all the utilized electrode arrays can establish the buried metallic and plastic mines correctly in dry and wet soil. The accuracy differs from one array to the other based on the relative resistivity contrast to the host soil and the subsurface distribution of current and potential lines as well as the amplitude of the noises in the data. The ERI technique proved to be fast and effective tool for detecting the non-metallic mines especially in the conductive environment whereas the performances of the other metal detector (MD) and GPR techniques show great limitation.
Ionospheric conductivity effects on electrostatic field penetration into the ionosphere
Authors: Denisenko V. V. , Boudjada M. Y. , Horn M. , Pomozov E. V. , Biernat H. K. , Schwingenschuh K. , Lammer H. , Prattes G. , Cristea E.
Published: April 2010

Abstract. The classic approach to calculate the electrostatic field penetration, from the Earth's surface into the ionosphere, is to consider the following equation ∇·(σ·∇Φ)=0 where σ and Φ are the electric conductivity and the potential of the electric field, respectively. The penetration characteristics strongly depend on the conductivities of atmosphere and ionosphere. To estimate the electrostatic field penetration up to the orbital height of DEMETER satellite (about 700 km) the role of the ionosphere must be analyzed. It is done with help of a special upper boundary condition for the atmospheric electric field. In this paper, we investigate the influence of the ionospheric conductivity on the electrostatic field penetration from the Earth's surface into the ionosphere. We show that the magnitude of the ionospheric electric field penetrated from the ground is inverse proportional to the value of the ionospheric Pedersen conductance. So its typical value in day-time is about hundred times less than in night-time.
Strategy to design the sea-level monitoring networks for small tsunamigenic oceanic basins: the Western Mediterranean case
Authors: Schindelé F. , Loevenbruck A. , Hébert H.
Published: April 2010

Abstract. The 26 December 2004 Indian Ocean tsunami triggered a number of international and national initiatives aimed at establishing modern, reliable and robust tsunami warning systems. In addition to the seismic network for initial warning, the main component of the monitoring system is the sea level network. Networks of coastal tide gages and tsunameters are implemented to detect the tsunami after the occurrence of a large earthquake, to confirm or refute the tsunami occurrence. Large oceans tsunami monitoring currently in place in the Pacific and in implementation in the Indian Ocean will be able to detect tsunamis in 1 h. But due to the very short time of waves propagation, in general less than 1 h, a tsunami monitoring system in a smaller basin requires a denser network located close to the seismic zones. A methodology is proposed based on the modeling of tsunami travel time and waveform, and on the estimation of the delay of transmission to design the location and the spacing of the stations. In the case of Western Mediterranean, we demonstrate that a network of around 17 coastal tide gages and 13 tsunameters located at 50 km along the shore is required to detect and measure nearly all tsunamis generated on the Northern coasts of Africa.
Empirical analysis of Japanese flood risk acceptability within multi-risk context
Authors: Zhai G. , Ikeda S.
Published: April 2010

Abstract. This paper establishes a framework of a multi-risk context for analyzing acceptable risk beyond single-risk context and empirically examines how other risks affects flood risk acceptability based on Rational Action Paradigm (RAP) by using a survey conducted in the Toki-Shonai River region of Japan. The main findings obtained by cross-sectional analysis and covariance structure analysis within a multi-risk context can be summarized as follows. – Nearly half of the respondents accept no flood risk at all. – Flood risk acceptability depends on not only on the factors of flood risk itself (e.g. frequency, consequence, and characteristics), but also other types of risks involved in our technological society. – Flood risk acceptability is associated with a multi-risk context. Whether a risk is accepted depends on its perceived importance relative to others as well as the balance of its cost and benefit. Providing budget information and ensuring preparedness for flood risk may also affect the acceptability.
Thunderstorm nowcasting by means of lightning and radar data: algorithms and applications in northern Italy
Authors: Bonelli P. , Marcacci P.
Published: April 2010

Abstract. Thunderstorms and their ground effects, such as flash floods, hail, lightning, strong winds, and tornadoes, are responsible for most weather damages in northern Italy, especially in the warm season from May to September. A nowcasting and warning system focused on severe thunderstorm events would be useful to reduce risks for people involved in outside activities and for electric, telecommunication, and sensitive industrial business. C-band radar and Lighting Location Systems provide useful, fast and high resolution data for the detection of convective systems and for following their dynamics. The whole of northern Italy is covered by radar with a resolution of 1 km and by a lightning network with a mean accuracy of 0.5 km on the single point of impact. The authors present an algorithm developed for tracking high intensity storm cells by means of radar and lightning data. Application to northern Italy reveals that tracking thunderstorm cells can be used as an alert system that may help prevent damages from extreme weather, as well as allowing for studying the correlation among lightning, rainfall and tornado occurrence. Assessing the algorithm skill is also discussed, and a forecast verification method is described and applied for the duration of a thunderstorm season.
A review of wave climate and prediction along the Spanish Mediterranean coast
Authors: Sánchez-Arcilla A. , González-Marco D. , Bolaños R.
Published: April 2010

Abstract. This paper reviews the characterization of wave storms along the Spanish/Catalan Mediterranean coast. It considers the "physical" and "statistical" description of wave parameters and how they are affected by the prevailing meteo patterns and the sharp gradients in orography and bathymetry. The available field data and numerically simulated wave fields are discussed from this perspective. The resulting limits in accuracy and predictability are illustrated with specific examples. This allows deriving some conclusions for both short-term operational predictions and a long-term climatic assessment.
Analysis of NOAA particle data and correlations to seismic activity
Authors: Fidani C. , Battiston R.
Published: April 2010

Abstract. A decade of NOAA-15 particle flux data offers an opportunity to test claims of correlations between seismic activity and effects on the ionosphere. Over the last two decades, potentially interesting observations in the ionosphere-magnetosphere transition region have been investigated. Specifically these consists of anomalous particle fluxes detected by several space experiments and correlated with the earthquake occurrence. These particle fluxes are characterised by anomalous short-term and sharp increases in high energy particle counting rates, referred to as particle bursts. In this work, more general rules for particle bursts selection have been defined and tested on the NOAA database, for particles inside and outside the South Atlantic Anomaly region. The whole period of ten years burst activity from NOAA-15 database is reported. Data from four satellites, NOAA-15, 16, 17 and 18, were analyzed during periods of solar quiet activity in connection with strong earthquakes, revealing presence of bursts detected on more than one satellite close to the time of the same seismic events. This preliminary study presented here concentrates on periods of major Indonesian earthquakes from 1998 to date, including Sumatra event M=9, during which geomagnetic Ap index was less than 16 and with no sudden ionospheric disturbances. During this period particle burst temporal distributions have shown some correspondence with earthquake times. The limits of the analysis presented in this papers are discussed as well as prospects for future work.
Identification of glacier motion and potentially dangerous glacial lakes in the Mt. Everest region/Nepal using spaceborne imagery
Authors: Bolch T. , Buchroithner M. F. , Peters J. , Baessler M. , Bajracharya S.
Published: April 2010

Abstract. Failures of glacial lake dams can cause outburst floods and represents a serious hazard. The potential danger of outburst floods depends on various factors like the lake's area and volume, glacier change, morphometry of the glacier and its surrounding moraines and valley, and glacier velocity. Remote sensing offers an efficient tool for displacement calculations and risk assessment of the identification of potentially dangerous glacial lakes (PDGLs) and is especially helpful for remote mountainous areas. Not all important parameters can, however, be obtained using spaceborne imagery. Additional interpretation by an expert is required. ASTER data has a suitable accuracy to calculate surface velocity. Ikonos data offers more detail but requires more effort for rectification. All investigated debris-covered glacier tongues show areas with no or very slow movement rates. From 1962 to 2003 the number and area of glacial lakes increased, dominated by the occurrence and almost linear areal expansion of the moraine-dammed lakes, like the Imja Lake. Although the Imja Lake will probably still grow in the near future, the risk of an outburst flood (GLOF) is considered not higher than for other glacial lakes in the area. Potentially dangerous lakes and areas of lake development are identified. There is a high probability of further lake development at Khumbu Glacier, but a low one at Lhotse Glacier.
Runoff generation dynamics within a humid river basin
Authors: Manfreda S.
Published: April 2010

Abstract. The present paper introduces an analytical approach for the description of the soil water balance and runoff production within a schematic river basin. The model is based on a stochastic differential equation where the rainfall is interpreted as an additive noise in the soil water balance and is assumed uniform over the basin, the basin heterogeneity is characterized by a parabolic distribution of the soil water storage capacity and the runoff production occurs for saturation excess. The model allowed to derive the probability density function of the produced surface runoff highlighting the role played by climate and physical characteristics of a basin on runoff dynamics. Finally, the model have been tested over a humid basin of Southern Italy proposing also a strategy for the parameters estimation.
Influence of check dams on debris-flow run-out intensity
Authors: Remaître A. , van Asch Th. W. J. , Malet J.-P. , Maquaire O.
Published: April 2010

Abstract. Debris flows are very dangerous phenomena claiming thousands of lives and millions of Euros each year over the world. Disaster mitigation includes non-structural (hazard mapping, insurance policies), active structural (drainage systems) and passive structural (check dams, stilling basins) countermeasures. Since over twenty years, many efforts are devoted by the scientific and engineering communities to the design of proper devices able to capture the debris-flow volume and/or break down the energy. If considerable theoretical and numerical work has been performed on the size, the shape and structure of check dams, allowing the definition of general design criteria, it is worth noting that less research has focused on the optimal location of these dams along the debris-flow pathway. In this paper, a methodological framework is proposed to evaluate the influence of the number and the location of the check dams on the reduction of the debris-flow intensity (in term of flow thickness, flow velocity and volume). A debris-flow model is used to simulate the run-out of the debris flow. The model uses the Janbu force diagram to resolve the force equilibrium equations; a bingham fluid rheology is introduced and represents the resistance term. The model has been calibrated on two muddy debris-flow events that occurred in 1996 and 2003 at the Faucon watershed (South French Alps). Influence of the check dams on the debris-flow intensity is quantified taking into account several check dams configurations (number and location) as input geometrical parameters. Results indicate that debris-flow intensity is decreasing with the distance between the source area and the first check dams. The study demonstrates that a small number of check dams located near the source area may decrease substantially the debris-flow intensity on the alluvial fans.