123 results
Search Results
2. Comment on the paper 'Earthquake Hazard Assessment in the Oran Region (Northwest Algeria)' by Youcef Bouhadad and Nasser Laouami
- Author
-
Mohamed Hamdache and José A. Peléez Montilla
- Subjects
Atmospheric Science ,Hydrogeology ,Natural hazard ,Earthquake hazard ,Earth and Planetary Sciences (miscellaneous) ,Magnitude (mathematics) ,North africa ,Seismic risk ,Cartography ,Geology ,Seismology ,Water Science and Technology - Published
- 2004
3. Hurricane event-based method to create regional hazard maps for heavy rainfall-induced translational landslides.
- Author
-
Jaimes, Miguel, Niño, Mauro, and Huerta, Benjamín
- Subjects
LANDSLIDE hazard analysis ,LANDSLIDE prediction ,GEOGRAPHIC information systems ,HURRICANES ,CARTOGRAPHY - Abstract
This paper proposes a hurricane event-based method to construct a map for heavy rainfall-induced translational landslides. This method involves five steps: (1) construct a GIS-based geotechnical database; (2) identify the areas in the vicinity which are susceptible to translational landslides based on the slope of the terrain and the geological information available; (3) characterize the heavy rainfall hazard due to hurricanes (typhoon) as a set of collectively exhaustive and mutually exclusive stochastic events, that fully describe spatial distribution and annual frequency of occurrence (in accordance with storm category, storm position, distance between the eye of the storm and the site of interest, among others factors); (4) compute the ratio between the steady-state rainfall produced by a hurricane event affecting the tributary area of the slope under analysis, Q, and the critical steady-state rainfall necessary to trigger slope instability, Q, and finally; (5) carry out a probabilistic translational landslide hazard analysis to estimate the exceedance rate of a given ratio Q/ Q. This method is applied to maps of Mexico for return periods of 50 and 150 years. The results shown in these maps are estimates of where the translational landslides may occur, and they should be useful to carry out local studies and to elaborate recommendations of site-specific hazard reduction plans as well as to calculate insurance rates. In addition to this, these results are useful for identifying actions of civil protection, regional and local risk management, and land use planning, as well as the promotion of more detailed vulnerability and risk studies on different scales. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
4. Flood inundation mapping sensitivity to riverine spatial resolution and modelling approach.
- Author
-
Papaioannou, G., Loukas, A., Vasiliades, L., and Aronica, G.
- Subjects
FLOODS ,CARTOGRAPHY ,HYDRAULIC engineering ,HYDRAULICS ,SENSITIVITY analysis ,MANAGEMENT - Abstract
An innovative approach in the investigation of complex landscapes for hydraulic modelling applications is the use of terrestrial laser scanner (TLS) that can lead to a high-resolution digital elevation model (DEM). Another notable factor in flood modelling is the selection of the hydrodynamic model (1D, 2D and 1D/2D), especially in complex riverine topographies, that can influence the accuracy of flood inundation area and mapping. This paper uses different types of hydraulic-hydrodynamic modelling approaches and several types of river and riparian area spatial resolution for the implementation of a sensitivity analysis for floodplain mapping and flood inundation modelling process at ungauged watersheds. Four data sets have been used for the construction of the river and riparian areas: processed and unprocessed TLS data, topographic land survey data and typical digitized contours from 1:5000-scale topographic maps. Modelling approaches combinations consist of: one-dimensional hydraulic models (HEC-RAS, MIKE 11), two-dimensional hydraulic models (MIKE 21, MIKE 21 FM) and combinations of coupled hydraulic models (MIKE 11/MIKE 21) within the MIKE FLOOD platform. Historical flood records and estimated flooded area derived from an observed extreme flash-flood event have been used in the validation process using 2 × 2 contingency tables. Flood inundation maps have been generated for each modelling approach and landscape configuration at the lower part of Xerias River reach at Volos, Greece, and compared for assessing the sensitivity of input data and model structure uncertainty. Results provided from contingency table analysis indicate the sensitivity of floodplain modelling on the DEM spatial resolution and the hydraulic modelling approach. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
5. A Robust Gaussian variogram estimator for cartography of hydrological extreme events
- Author
-
Gutierrez-Lopez, Alfonso
- Published
- 2021
- Full Text
- View/download PDF
6. Methodological approach for mapping the flood physical vulnerability index with geographical open-source data: an example in a small-middle city (Ponferrada, Spain)
- Author
-
Tascón-González, Laura, Ferrer-Julià, Montserrat, and García-Meléndez, Eduardo
- Published
- 2024
- Full Text
- View/download PDF
7. Modeling of SMF tsunami hazard along the upper US East Coast: detailed impact around Ocean City, MD.
- Author
-
Grilli, Stephan, O'Reilly, Christopher, Harris, Jeffrey, Bakhsh, Tayebeh, Tehranirad, Babak, Banihashemi, Saeideh, Kirby, James, Baxter, Christopher, Eggeling, Tamara, Ma, Gangfeng, and Shi, Fengyan
- Subjects
EARTHQUAKE hazard analysis ,TSUNAMI hazard zones ,CARTOGRAPHY ,HURRICANES - Abstract
With support from the US National Tsunami Hazard Mitigation Program (NTHMP), the authors have been developing tsunami inundation maps for the upper US East Coast (USEC), using high-resolution numerical modeling. These maps are envelopes of maximum elevations, velocity, or momentum flux, caused by the probable maximum tsunamis identified in the Atlantic oceanic basin, including from far-field coseismic or volcanic sources, and near-field Submarine mass failures (SMFs); the latter are the object of this work. Despite clear field evidence of past large-scale SMFs within our area of interest, such as the Currituck slide complex, their magnitude, pre-failed geometry, volume, and mode of rupture are poorly known. A screening analysis based on the Monte Carlo simulations (MCS) identified areas for possible tsunamigenic SMF sources along the USEC, indicating an increased level of tsunami hazard north of Virginia, potentially surpassing the inundation generated by a typical 100-year hurricane storm surge in the region, as well as that from the most extreme far-field coseismic sources in the Atlantic; to the south, the MCS indicated that SMF tsunami hazard significantly decreased. Subsequent geotechnical and geological analyses delimited four high-risk areas along the upper USEC where the potential for large tsunamigenic SMFs, identified in the MCS, was realistic on the basis of field data (i.e., sediment nature and volume/availability). In the absence of accurate site-specific field data, following NTHMP's recommendation, for the purpose of simulating tsunami hazard from SMF PMTs, we parameterized an extreme SMF source in each of the four areas as a so-called Currituck proxy, i.e., a SMF having the same volume, dimensions, and geometry as the historical SMF. In this paper, after briefly describing our state-of-the-art SMF tsunami modeling methodology, in a second part, we parameterize and model the historical Currituck event, including: (1) a new reconstruction of the SMF geometry and kinematics; (2) the simulation of the resulting tsunami source generation; and (3) the propagation of the tsunami source over the shelf to the coastline, in a series of nested grids. A sensitivity analysis to model and grid parameters is performed on this case, to ensure convergence and accuracy of tsunami simulation results. Then, we model in greater detail and discuss the impact of the historical Currituck tsunami event along the nearest coastline where its energy was focused, off of Virginia Beach and Norfolk, as well as near the mouth of the Chesapeake Bay; our results are in qualitative agreement with an earlier modeling study. In a third part, following the same methodology, we model tsunami generation and propagation for SMF Currituck proxy sources sited in the four identified areas of the USEC. Finally, as an illustration of our SMF tsunami hazard assessment work, we present detailed tsunami inundation maps, as well as some other products, for one of the most impacted and vulnerable areas, near and around Ocean City, MD. We find that coastal inundation from near-field SMF tsunamis may be comparable to that caused by the largest far-field sources. Because of their short propagation time and, hence, warning times, SMF tsunamis may pose one of the highest coastal hazards for many highly populated and vulnerable communities along the upper USEC, certainly comparable to that from extreme hurricanes. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
8. Data-driven mapping of avalanche release areas: a case study in South Tyrol, Italy.
- Author
-
Pistocchi, A. and Notarnicola, C.
- Subjects
CARTOGRAPHY ,AVALANCHES ,CASE studies ,MOUNTAINS ,LOGISTIC regression analysis - Abstract
Avalanche hazard and risk mapping is of utmost importance in mountain areas in Europe and elsewhere. Advanced methods have been developed to describe several aspects of avalanche hazard assessment, such as the dynamics of snow avalanches or the intensity of snowfall to assume as a reference meteorological forcing. However, relatively little research has been conducted on the identification of potential avalanche release areas. In this paper, we present a probabilistic assessment of potential avalanche release areas in the Italian Autonomous Province of Bolzano, eastern Alps, using the Weights of Evidence and Logistic Regression methods with commonly available GIS datasets. We show that a data-driven statistical model performs better than simple, although widely adopted, screening criteria that were proposed in the past, although the complexity of observed release areas is only partly captured by the model. In the best case, the model enables predicting about 70 % of avalanches in the 20 % of area classified at highest hazard. Based on our results, we suggest that probabilistic identification of potential release areas could provide a useful aid in the screening of sites for subsequent, more detailed hazard assessment. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
9. Evaluation of soil collapse potential in regional scale.
- Author
-
Momeni, Mehdi, Shafiee, Ali, Heidari, Mojtaba, Jafari, Mohammad, and Mahdavifar, Mohammad
- Subjects
SOIL mechanics ,RISK assessment for landslides ,CARTOGRAPHY ,FUZZY sets ,ENGINEERING geology - Abstract
Collapsible soils have considerable strength and stiffness in their dry natural state but settle dramatically when they become wet. This paper documents a low-cost, qualitative evaluation scheme using fuzzy set analysis to determine site collapsibility based on subjective knowledge of the geological, geotechnical, and environmental conditions and their uncertainty. For each category, factors or subcategories were defined in a decision tree based on relevant literature. Each category and subcategory was then weighted or rated using linguistic terms developed from expert assessment. The linguistic data or information obtained from the assessments was represented and processed using fuzzy sets. To calibrate the criteria, 87 collapse potential tests were performed on undisturbed soil samples gathered from 27 different locations throughout Iran, leading to the definition of a standard collapse potential fuzzy set. Finally, on the basis of the established criteria, a collapse potential map was prepared for a suburban area in the western part of the city of Kerman, Iran. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
10. An assessment of educational tsunami evacuation map designs in Washington and Oregon.
- Author
-
Kurowski, Maciej, Hedley, Nick, and Clague, John
- Subjects
TSUNAMIS ,CIVILIAN evacuation ,CARTOGRAPHY - Abstract
Educational tsunami evacuation map brochures in Washington and Oregon have been developed locally, resulting in significant differences between the types of tsunami hazard information they include. This paper identifies six tsunami hazard information types present in 38 brochures in Washington and Oregon: (1) tsunami hazard zone, (2) road network, (3) assembly areas, (4) evacuation guidance, (5) infrastructure, and (6) terrain. It compares and contrasts these information types in the maps and text of six of the brochures, including a proposed design standard in Oregon. Design differences of all 38 brochure maps are then organized using principles of cartographic abstraction, which describe mapmaker decisions about selection, generalization, and symbolization of information. We further use this framework to situate the information content of a new interactive Google Maps tool in Oregon. Our assessment identifies limitations of current tsunami hazard information that may be relevant to improving tsunami education. In theory, more advanced evacuation map tools can play an important role in reducing the limitations of tsunami hazard information relevant to the public. The new Google Maps tool addresses few of these limitations. Recognizing how map-making decisions define the underlying information content of evacuation maps can facilitate much needed future evaluations and developments in evacuation map design. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
11. The 1979 nice airport tsunami: mapping of the flood in Antibes.
- Author
-
Sahal, Alexandre and Lemahieu, Anne
- Subjects
TSUNAMIS ,AIRPORTS ,FLOODS ,CARTOGRAPHY ,GEODATABASES - Abstract
On 16 October 1979, a tsunami of a local origin hits the French Riviera around Nice, France, killing 8 people and generating important economic losses. Its impact was felt from Hyères to Menton, France. The main effect of this tsunami was flooding in the neighborhoods of La Salis and La Garoupe, Antibes, France. A synthesis of unpublished reports written in the context of an administrative investigation was conducted. Various archives were also consulted (newspapers, fire and rescue unit reports, insurance reports, etc.), and a field survey was organized in 2009 to record testimonies from the inhabitants who witnessed the flood in La Salis, Antibes, the area where the effects of the tsunami were the greatest. A geo-database of the neighborhood of La Salis was built using available aerial imagery, land cover data and digital terrain models, to reconstruct the surface of the flooded area as it was in 1979 and as it is now. Comparing precise testimonies and the 1979 topographic information available allowed the authors to precisely map the flood and to deduce the runup values which reached 3.5 m locally, with a maximal distance of flooding of 150 m inland. This paper provides modelers with precious information about the extent of flooding and the time sequence in order to reconstitute the propagation and flooding of the 16 October 1979 tsunami. This information highlights the fact that the French Riviera is a low hazard, but high vulnerability area. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
12. Recent seismicity in Delhi and population exposure to seismic hazard
- Author
-
Sreevalsa Kolathayar
- Subjects
Atmospheric Science ,education.field_of_study ,Population ,Induced seismicity ,Hazard map ,Hazard ,Seismic hazard ,Geography ,Contour line ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Seismic risk ,education ,Cartography ,Water Science and Technology - Abstract
This paper makes an attempt to review historical and recent seismicity in Delhi and presents updated seismic hazard map of Delhi integrated with ward-wise classified population data. Earthquakes are not destructive unless other factors that enhance the damage prevail. Population density and types or quality of buildings in an area are two such important factors that affect the risk during any hazards, particularly an earthquake. This paper presents the details of the seismic hazard analysis for Delhi with the latest available information on earthquakes and seismic sources within 300 km radius around the city, using state-of-the-art deterministic approach. Ten different attenuation relationships developed for the active tectonic region were considered in the present study. They were ranked using log-likelihood method. Ward-wise population maps along with classified population maps were developed based on the 2011 census data. Hazard contour map and population maps are presented in this paper to revisit the seismic risk prevailing in the region. An attempt was made to overlay the hazard map with population maps showing the distribution of various classes of the population that reflects the seismic risk exposure to different wards of Delhi.
- Published
- 2021
13. Documentary proxies and interdisciplinary research on historic geomorphologic hazards: a discussion of the current state from a central European perspective
- Author
-
Tomáš Strnad, Antonín Kadlec, Alena Hrbáčová, Pavel Raška, Jakub Dubišar, and Vilém Zábranský
- Subjects
Atmospheric Science ,History ,business.industry ,Perspective (graphical) ,Distribution (economics) ,Historiography ,Hazard ,Section (archaeology) ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Economic impact analysis ,business ,Positivism ,Environmental planning ,Cartography ,Water Science and Technology - Abstract
During the last two decades, documentary data (written and iconographic sources) have been increasingly employed in geomorphologic research aiming at reconstruction of territorial distribution, temporal occurrence and social and economic impacts of various geomorphologic hazards. The goal of this paper is to broaden the previous discussion (Glade et al. The use of historical data in natural hazard assessments. Kluwer, Dordrecht, 2001) of the methodological constraints on the use of documentary data for geomorphologic hazard research. Using the interdisciplinary approach of geomorphology, historiography and medial studies, we firstly summarise the major finding of papers that have employed various types of documentary data sources to study geomorphologic hazards in different regions. In the second section, we present case studies from the Czech Republic resulting from the ongoing research project that is devoted to the assessment of the potential of documentary data to reconstruct past occurrences of and mitigation strategies for geomorphologic hazards. Finally, we discuss three main methodological issues emerging from our research: (a) problems emerging from the positivist approach to documentary data sources and the necessity for critical analyses of documentary data sources based on modern historiographic approaches, (b) constraints arising from the combination of documentary data from different spatiotemporal scales and (c) lacks in the use of documentary data to study local-based adaptation strategies to cope with geomorphologic hazards.
- Published
- 2013
14. Extracting building stock information from optical satellite imagery for mapping earthquake exposure and its vulnerability
- Author
-
Daniele Ehrlich, Pierre Soille, Xavier Blaes, and Thomas Kemper
- Subjects
Very high resolution ,Atmospheric Science ,Computer science ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Added value ,Image processing ,Satellite imagery ,Cartography ,Stock (geology) ,Water Science and Technology ,Remote sensing - Abstract
The paper focuses on automatic extraction building stock information for quantifying physical exposure and its vulnerability from High and Very High Resolution (VHR) optical satellite imagery. We use two case studies. In Sana’a (Yemen) we use automatic techniques to extract the building stock as well as building height that is used to characterize its vulnerability. In Port-au-Prince (Haiti) – in the area affected by the 2010 earthquake -we map the building stock based on a pre-disaster imagery – and we show the added value of area based information when added to point based damage assessment from visual change interpretation of post disaster aerial images. The paper shows that VHR imagery can be used to locate and quantify the building stock and its height. This paper also shows that damages measured from changes detected from pre-and post-disaster imagery can in principle map and provide vulnerability information related to the structural fragility of the building stock., JRC.G.2-Global security and crisis management
- Published
- 2012
15. Optical satellite imagery for quantifying spatio-temporal dimension of physical exposure in disaster risk assessments
- Author
-
Patrizia Tenerelli and Daniele Ehrlich
- Subjects
Atmospheric Science ,Computer science ,Image processing ,Land cover ,Footprint ,Remote sensing (archaeology) ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Satellite imagery ,Cartography ,Built environment ,Change detection ,Water Science and Technology ,Remote sensing - Abstract
This work addresses the use of remote sensing imagery to quantify the built environment and its spatial and temporal changes. It identifies building footprint map, building location map and built-up area map as information products that can be used to quantify physical exposure, one of the variables required in disaster risk assessments. The paper also reviews urban land use maps and urban classes in land cover maps as potential source for deriving exposure information. The paper focuses on the latest generation of satellite-borne remote sensing imaging systems that deliver high-resolution optical imagery able to resolve buildings and other three-dimensional man-made constructions. This work also reviews the semantics, the spatial unit used to define physical exposure, image processing procedures and change techniques.
- Published
- 2012
16. A fast GIS-based risk assessment for tephra fallout: the example of Cotopaxi volcano, Ecuador-Part II: vulnerability and risk assessment
- Author
-
Sébastien Biass, Costanza Bonadonna, and Corine Frischknecht
- Subjects
Atmospheric Science ,Volcanic hazards ,Cotopaxi ,business.industry ,Global Volcanism Program ,Volcanic hazard ,Vulnerability ,Tephra dispersion ,Hazard analysis ,GIS ,Hazard ,Natural hazard ,ddc:550 ,Earth and Planetary Sciences (miscellaneous) ,Ecuador ,Physical geography ,business ,Risk assessment ,Tephra ,Cartography ,Volcanic risk ,Geology ,Risk management ,Water Science and Technology - Abstract
In order to develop efficient strategies for risk mitigation and emergency management, planners require the assessment of both the expected hazard (frequency and magnitude) and the vulnerability of exposed elements. This paper presents a GIS-based methodology to produce qualitative to semi-qualitative thematic risk assessments for tephra fallout around explosive volcanoes, designed to operate with datasets of variable precision and resolution depending on data availability. Due to the constant increase in population density around volcanoes and to the wide dispersal of tephra from volcanic plumes, a large range of threats, such as roof collapses, damage to crops, blockage of vital lifelines and health problems, concern even remote communities. To address these issues, we have assessed the vulnerability and the risk levels for five themes relevant to tephra fallout: (1) social, (2) economic, (3) environmental, (4) physical and (5) territorial. Risk and vulnerability indices for each theme are averaged to the fourth level of administrative unit (parroquia, parish). In a companion paper, Biass and Bonadonna (this volume) present a probabilistic hazard assessment for tephra fallout at Cotopaxi volcano (Ecuador) using the advection-diffusion model TEPHRA2, which is based on field investigations and a global eruption database (Global Volcanism Program, GVP). The scope of this paper is to present a new approach to risk assessment specifically designed for tephra fallout, based on a comprehensive hazard assessment of Cotopaxi volcano. Our results show that an eruption of moderate magnitude (i.e. VEI 4) would result in the possible collapse of ∼9,000 houses in the two parishes located close to the volcano. Our study also reveals a high risk on agriculture, closely linked to the economic sector, and a possible accessibility problem in case of an eruption of any size, as tephra is likely to affect the only major road running from Quito to Latacunga (Panamerican Highway). As a result, this method fits into the ongoing effort to better characterize and evaluate volcanic risk, and more specifically the risk associated with tephra fallout. Although this methodology relies on some assumptions, it can serve as a rapid and efficient starting point for further investigations of the risk level around explosive volcanoes.
- Published
- 2012
17. Landslide hazard and risk assessment: a case study from the Hlohovec–Sered’ landslide area in south-west Slovakia
- Author
-
Işık Yilmaz, Marian Marschalko, Martin Bednarik, and [Yilmaz, Isik] Cumhuriyet Univ, Fac Engn, Dept Geol Engn, TR-58140 Sivas, Turkey -- [Bednarik, Martin] Comenius Univ, Fac Nat Sci, Dept Engn Geol, Bratislava 84215, Slovakia -- [Marschalko, Marian] Tech Univ Ostrava, Inst Geol Engn, Fac Min & Geol, Ostrava 70833, Czech Republic
- Subjects
Risk ,Slovakia ,Atmospheric Science ,Vulnerability ,Landslide ,Bivariate analysis ,Landslide susceptibility ,Hazard map ,Hazard ,Susceptibility ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Risk assessment ,Cartography ,Geology ,Seismology ,Water Science and Technology - Abstract
WOS: 000308329900030, Landslide hazard or susceptibility assessment is based on the selection of relevant factors which play a role on the slope instability, and it is assumed that landslides will occur at similar conditions to those in the past. The selected statistical method compares parametric maps with the landslide inventory map, and results are then extrapolated to the entire evaluated territory with a final product of landslide hazard or susceptibility map. Elements at risk are defined and analyzed in relation with landslide hazard, and their vulnerability is thus established. The landslide risk map presents risk scenarios and expected financial losses caused by landslides, and it utilizes prognoses and analyses arising from the landslide hazard map. However, especially the risk scenarios for future in a selected area have a significant importance, the literature generally consists of the landslide susceptibility assessment and papers which attempt to assess and construct the map of the landslide risk are not prevail. In the paper presented herein, landslide hazard and risk assessment using bivariate statistical analysis was applied in the landslide area between Hlohovec and Sered' cities in the south-western Slovakia, and methodology for the risk assessment was explained in detail.
- Published
- 2012
18. A comparative analysis of the loss of life during two recent floods in France: the sea surge caused by the storm Xynthia and the flash flood in Var
- Author
-
Stéphanie Defossez, Freddy Vinet, L. Boissier, Darren Lumbroso, Gouvernance, Risque, Environnement, Développement (GRED), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), and Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [France-Sud])
- Subjects
Atmospheric Science ,education.field_of_study ,010504 meteorology & atmospheric sciences ,Flood myth ,Population ,0207 environmental engineering ,Vulnerability ,Storm surge ,Storm ,[SHS.GEO]Humanities and Social Sciences/Geography ,02 engineering and technology ,01 natural sciences ,humanities ,Geography ,Natural hazard ,Preparedness ,Earth and Planetary Sciences (miscellaneous) ,Flash flood ,020701 environmental engineering ,Socioeconomics ,education ,Cartography ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
This paper aims to analyse and compare the loss of life that occurred during two recent floods in France. The first flood was due to a sea surge triggered by the storm called Xynthia that hit the Atlantic coast on 28 February 2010 (41 flood-related deaths). The second was a flash flood that struck the Var Department in the French Mediterranean region on 15 June 2010 (26 fatalities). After detailing the assumptions and expected outcomes of the study of disaster-related fatalities, the paper focuses on the characteristics of the victims and the circumstances of their deaths. In the first case, 71% of the victims were people aged over 60 (mainly women) who were surprised while they were sleeping and who died in or near their homes. In the case of the flash flood, the profiles of the victims were diverse as the flooding occurred in the afternoon and many people were trapped in open. The paper also highlights the factors that explain mortality. Physical factors such as water depth were determined. The relationship between the water depth and the age of victims was found to be relevant. In the case of the storm surge Xynthia, the correlation between age and water depth is positive. For the flash flood, the correlation between age and water depth was negative as male adults died in open. In the first case, the vulnerability of people was closely linked to human features such as type of housing and age that people are not directly responsible for. During flash floods, dangerous behaviour by people highlighted the role of risk-taking in loss of life. We also examined the particular case of the deaths of the children. The paper concludes by discussing the factors of vulnerability on frail population such as elderly people or marginalized. The lack of risk awareness and crisis preparedness were clearly a major factor of vulnerability.
- Published
- 2011
19. Participatory model assessment of earthquake-induced landslide hazard models
- Author
-
Scott B. Miles
- Subjects
Atmospheric Science ,Process management ,Computer science ,Best practice ,Site selection ,Landslide ,Outcome (game theory) ,Hazard ,Task (project management) ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Set (psychology) ,Cartography ,Water Science and Technology - Abstract
The study described in this paper investigates the relative merits of two peer-reviewed earthquake-induced landslide models using participatory model assessment. The earthquake-induced landslide hazard models assessed are a simplified Newmark’s displacement model and a recently developed knowledge-based model. Participatory model assessment involves conducting facilitated participatory processes where the model(s) are used for aiding decisions within a socio-behavioral experiment designed for collecting data to evaluate formal hypotheses about the model(s). The paper sets out the design of the participatory model assessment—a series of workshops involving experts and potential model end-users that incorporated a roleplay site selection task. Quantitative data elicited using a set of entrance and exit questionnaires were analyzed to investigate hypotheses about the models. Participants found the knowledge-based model to be significantly more complete and more informative for their roleplay task. Overall, the two models did not yield significant differences with respect to issues such as task efficiency or task outcome satisfaction. Lastly, it was found that education level and disciplinary perspectives (of those analyzed) did not significantly affect outcomes, suggesting that a wide demographic of participants can be used for participatory model assessments. Additional research is needed to assess the models in different contexts, as well as more broadly developing a set of best practices for conducting participatory model assessments of other natural hazard and risk models intended to support decision-making.
- Published
- 2010
20. Disaster risk reduction on non-sovereign islands: La Réunion and Mayotte, France
- Author
-
Virginie Le Masson and Ilan Kelman
- Subjects
Risk analysis ,Atmospheric Science ,Engineering ,Disaster risk reduction ,business.industry ,Vulnerability ,Sovereignty ,Vulnerability assessment ,Natural hazard ,Development economics ,Earth and Planetary Sciences (miscellaneous) ,Mainland ,Baseline (configuration management) ,business ,Cartography ,Water Science and Technology - Abstract
The Islands of Reunion and Mayotte are French territories in the Indian Ocean and are prone to numerous and recurrent hazards as well as to increasing vulnerabilities. This paper examines disaster risk reduction on non-sovereign islands through the case studies of Reunion and Mayotte. The approach used is embedded in standard geographical approaches to risk analysis, focusing on place-based vulnerability, in order to understand disaster risk and disaster risk reduction on both islands. In addition to establishing baseline information and visiting both islands for further data, 21 semi-structured individual interviews were completed to understand the people’s perceptions of the hazards and of their vulnerabilities. Disaster risk reduction strategies, and attitudes from governing bodies implementing the strategies, tend to assume similar vulnerability contexts as mainland France, despite obvious differences on the islands. Many policies are implemented in a top–down manner by those from mainland France who have little interest in, and who do not fully take into consideration, local realities. This paper contributes new case studies to the literature, especially in comparing two non-Anglophone non-sovereign islands, and reinforces recommendations factoring in local contexts when addressing ‘vulnerability of a place’ to disasters.
- Published
- 2010
21. Building models for automatic landslide-susceptibility analysis, mapping and validation in ArcGIS
- Author
-
R. El Hamdouni, J. Chacón, J. D. Jiménez-Perálvarez, and C. Irigaray
- Subjects
Atmospheric Science ,Geographic information system ,Mathematical model ,business.industry ,Computer science ,Elevation ,Geoprocessing ,Landslide ,Set (abstract data type) ,Earth and Planetary Sciences (miscellaneous) ,Stage (hydrology) ,Digital elevation model ,business ,Cartography ,Water Science and Technology - Abstract
In this paper, ModelBuilderTM in ArcGIS (ESRI) has been applied to landslide-susceptibility analysis, mapping and validation. The models (scripts), available for direct downloading as an ArcGIS tool, allow landslide susceptibility to be computed in a given region, providing a landslide-susceptibility map, with the GIS matrix method, and ensuring a quality validation. The paper details the steps needed for the model-building process, enabling users to build their own models and to become more familiar with the tool. The susceptibility model leads the user first through a Digital Elevation Model (DEM), depicting the morphological and morphometric features of the study area, and then through a Digital Terrain Model (DTM), useful as a source of landslide-determinant factors, such as slope elevation, slope angle and slope aspect. In addition, another determinant factor is the lithological unit, independent of the DEM. Once the determinant landslide factors are reclassified and in a vectorial format, all the combinations between the classes of these factors are determined using the geoprocessing abilities of ArcGIS. The next step for the development of the landslide-susceptibility model consists of identifying the areas affected by a given surface of rupture (i.e. source area) in every combination of the determinant-factor classes. This step leads to the landslide matrix based on a previously georeferenced landslide database of the region, in which the slopes are distinguished into two simple classes: with or without landslides. In the last stage, to build a landslide-susceptibility model, the user computes the percentages of area affected by landslides in every combination of determinant factors. In the resulting landslide-susceptibility map a progressive zonation of areas or slopes increasingly prone to landslides is performed. A model for the validation of the resulting landslide-susceptibility map is also presented, based on the determination of the degree of fit, which is calculated from the cross tabulation between a set of landslides (not included in the susceptibility analysis) and the corresponding susceptibility map.
- Published
- 2008
22. Estimating Injury and Loss of Life in Floods: A Deterministic Framework
- Author
-
David Ramsbottom, Suresh Surendran, Edmund C. Penning-Rowsell, and Peter Floyd
- Subjects
Atmospheric Science ,geography ,Flood warning ,geography.geographical_feature_category ,Floodplain ,Flood myth ,business.industry ,fungi ,Flooding (psychology) ,Environmental resource management ,food and beverages ,Poison control ,Natural hazard ,parasitic diseases ,Injury prevention ,Earth and Planetary Sciences (miscellaneous) ,population characteristics ,business ,Risk assessment ,Cartography ,geographic locations ,Water Science and Technology - Abstract
This paper presents an outline methodology and an operational framework for assessing and mapping the risk of death or serious harm to people from flooding, covering death and physical injuries as a direct and immediate consequence of deep and/or fast flowing floodwaters (usually by drowning), and deaths and physical injuries associated with the flood event (but occurring in the immediate aftermath). The main factors that affect death or injury to people during floods include flow velocity, flow depth, and the degree to which people are exposed to the flood. The exposure potential is related to such factors as the “suddenness” of flooding (and amount of flood warning), the extent of the floodplain, people’s location on the floodplain, and the character of their accommodation. In addition, risks to people are affected by social factors including their vulnerability and behaviour. A methodology is described for estimating the likely annual number of deaths/injuries. This is based on defining zones of different flood hazard and, for each zone, estimating the total number of people located there, the proportion that are likely to be exposed to a flood, and the proportion of those exposed who are likely to be injured or killed during a flood event. The results for each zone are combined to give an overall risk for each flood cell and/or community. The objective of the research reported here is to develop a method which could be applied using a map-based approach in which flood risks to people are calculated and displayed spatially for selected areas or communities. The information needed for each part of the process is described in the paper, and the further research to provide the required information is identified.
- Published
- 2005
23. [Untitled]
- Author
-
Md. Rashed Chowdhury
- Subjects
Atmospheric Science ,education.field_of_study ,Government ,geography.geographical_feature_category ,Environmental change ,Flood myth ,Floodplain ,Population ,Geography ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Willingness to accept ,Risk assessment ,Socioeconomics ,education ,Cartography ,Water Science and Technology - Abstract
This paper aims to examine the impact of large-scale structuraladjustments (like the Greater Dhaka Flood Protection Project, GDFPP) on local living environment.It focuses the importance of environmental factors in flood hazard mitigation, and examines theenvironmental attitudes of the floodplain residents arising from the large-scale structural adjustments.Based on `perceived natural hazard research perspectives', this paper examines: (i) the reasons for persistentfloodplain occupation, and (ii) the importance of environmental factors in the choice, motivations and decision-makingof floodplain residents. This research used data collected from 300 households situated inthe eastern part of Dhaka. The face-to-face household survey data provided individuals' responses to a structuredquestionnaire on hazards and environment. Survey concerned urban floodplains, and looked fordata on housing, household characteristics, and residents' attitudes. Results of interview surveys wereused to: (i) explore the reasons of floodplain occupation, and (ii) residents' attitudes to tolerable levelof flood risk and willingness to accept environmental change resulting from the proposed structural embankments inthe eastern perimeter of Dhaka City, Bangladesh. Findings revealed that floodplain occupation (by theindividuals' decision-making) was a result of overall reaction to the Government's structuraladjustment policies that resulted from institutional, locational and socio-economic factors. The attitude survey results provided residents' perception to hazards and environment to be dependenton the socio-economic factors – but in a complex manner, many factors are interrelated.In addition to support for structural embankments, the study sample displayed a common concernand widespread environmental awareness. In terms of any `trade-off' between thebenefits (resources) from the embankments and costs (hazards) due to the detrimental impact on environment, the residents of Dhaka, despite some concern forsacrificing embankments for environment, tended to show a generalconsensus for embankments.
- Published
- 2003
24. [Untitled]
- Author
-
Linda Anderson-Berry
- Subjects
Atmospheric Science ,Vulnerability ,Poison control ,Storm surge ,Hazard ,Geography ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Survey data collection ,Cyclone ,Tropical cyclone ,Socioeconomics ,Cartography ,Water Science and Technology - Abstract
This paper is a partial discussion of a four-year study that investigated the vulnerability of the people living in the Cairns region to the tropical cyclone hazard. The longitudinal case study, focussing on the Cairns Northern Beaches area, was unique in that it included a social and societal `pre-cyclone impact' evaluation of various resident communities within the region, and then two consecutive `post-cyclone impact' studies. The primary research method supported an inductive qualitative approach to the collection and analysis of survey data. Some quantitative methods were invoked to support qualitative research findings. Survey data was collected in five separate questionnaire-based social surveys that were administered between 1996 and 2000. During the study, residents experiencedthe direct impact of two land-falling tropical cyclones. In addition to this, targeted andfocussed tropical cyclone awareness education was made increasingly available withinthe community. The social and demographic attributes that influence the individual'sperception of risk and contribute to our understanding of community vulnerability were examined and evaluated. Changes in the residents' attitudes, cyclone preparednessbehaviours and willingness to respond to cyclone warnings were monitored and measured. Analysis of early survey data indicated that community residents generally had some knowledge of cyclones but a limited understanding of cyclone processes and very little direct personal experience of the cyclone hazard. Individually and collectively, residents frequently demonstrated a biased perception of the risks associated with cyclones. The resident community was shown to be fragmented, with limited support being available to individual households. Initially, residents were found to be poorly prepared for cyclones and unlikely to respond to warnings appropriately. It appeared that, in the event of a land-falling tropical cyclone impacting the area, the community was highly vulnerable to unnecessary loss of property, livelihood and – in extreme circumstances – life. By 2000, Cairns community residents were somewhat better informed about cyclones and certainly more experienced. This paper provides some insight into how cyclone experience and education may synergisticly have contributed to a change in risk perceptions and a reduction in the vulnerability of Cairns residents to the tropical cyclone and storm surge hazards.
- Published
- 2003
25. [Untitled]
- Author
-
Dale Dominey-Howes
- Subjects
Value (ethics) ,Estimation ,Atmospheric Science ,education.field_of_study ,Emergency management ,business.industry ,Population ,Environmental resource management ,Hazard ,Work (electrical) ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,education ,business ,Risk assessment ,Cartography ,Geology ,Water Science and Technology - Abstract
Understanding the nature and impacts of tsunamis within the Aegean Sea region ofGreece is of importance to both the academic community and those organisationsconcerned with tsunami disaster management. In order to determine hazard and riskand consequently pre-plan mitigative strategies, it is necessary to analyse historical(documentary) and geological records of former tsunami events. Therefore, firstlythis paper provides a summary of the written sources of information on Aegeantsunamis paying particular attention to published catalogues. From the availabledata, it is noted that a large number of events have been reported during the last3500 years. Secondly, the paper provides a review of the published on-shore(terrestrial) geological records of tsunamis within the region. From this analysisit is seen that little geological evidence has been identified for the large numberof tsunamis reported in the catalogues. Thirdly, the paper considers the reliabilityof the written and geological records and how problems of accuracy, coverage,extent and reliability, may have potential implications for the estimation of hazardand risk. The paper concludes by making recommendations for disaster managers,geologists and historians to work closely together.
- Published
- 2002
26. [Untitled]
- Author
-
Aniello Amendola, Yuri Ermoliev, Tatiana Ermolieva, Joanne Linnerooth-Bayer, G. Koff, and V. G. Gitis
- Subjects
Atmospheric Science ,Insolvency ,business.industry ,Stochastic modelling ,Computer science ,Vulnerability ,Risk analysis (engineering) ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Stochastic optimization ,Seismic risk ,business ,Insurability ,Cartography ,Risk management ,Water Science and Technology - Abstract
This paper describes a spatial-dynamic, stochastic optimization model that takes account of the complexities and dependencies of catastrophic risks. Following a description of the general model, the paper briefly discusses a case study of earthquake risk in the Irkutsk region of Russia. For this purpose the risk management model is customized to explicitly incorporate the geological characteristics of the region, as well as the seismic hazards and the vulnerability of the built environment. In its general form, the model can analyze the interplay between investment in mitigation and risk-sharing measures. In the application described in this paper, the model generates insurance strategies that are less vulnerable to insolvency.
- Published
- 2000
27. Mapping heatwave vulnerability in Korea.
- Author
-
Kim, Do-Woo, Deo, Ravinesh, Lee, Jong-Seol, and Yeom, Jong-Min
- Subjects
CARTOGRAPHY ,NATURAL disasters ,STATISTICAL correlation ,REGRESSION analysis ,ECOLOGY - Abstract
Due to the inevitable increase in temperatures that are attributable to significant climate variability and notable shifts in climate under increasing greenhouse gases, heat waves are becoming a major natural disaster. They lead to elevating incidences of human mortality, health risks, and damage to the economy, agriculture, and natural ecosystems. As a precautionary foresight to mitigate detrimental impacts of this disaster, a better understanding of regional vulnerability to heat waves is essential. This study has investigated the cumulative role of the social and climatic factors on heatwave-related deaths across the 232 administrative counties in Korea. Correlation and clustering analyses performed on heatwave-related deaths and social and climatic factors indicated that the number of heatwave days, tropical nights, elderly living alone, and agricultural workers had a significant relationship with the number of heatwave-related deaths. In order to demonstrate the practicality of this approach for heatwave analysis, a spatial heatwave vulnerability map was created to identify the distribution of heatwave risk by compositing the four most significant vulnerability factors identified with regression method. Among the several available regression methods that are applied on countable data, this study has utilized zero-inflated Poisson regression because the available data on heatwave-related deaths included many zeros. The heatwave vulnerability map depicted well the actual distribution of heatwave-related deaths, particularly for counties with a large number of heatwave deaths. In light of this evidence, it is postulated that the heatwave vulnerability map can be used as a useful decision-making tool that can help facilitate efficient utilization of various disaster management resources at the national level and also to identify emphatically the heatwave-related risk over spatial scales to aid in the establishment of customized health risk precautionary measures. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
28. The great Minoan eruption of Thera volcano and the ensuing tsunami in the Greek Archipelago
- Author
-
John A. Antonopoulos
- Subjects
Atmospheric Science ,geography ,geography.geographical_feature_category ,media_common.quotation_subject ,Empire ,Poison control ,Ancient history ,Politics ,Bronze Age ,Natural hazard ,Archipelago ,Earth and Planetary Sciences (miscellaneous) ,Submarine volcano ,Cartography ,Geology ,Minoan civilization ,Water Science and Technology ,media_common - Abstract
The eastern Mediterranean has been the cradle of many great civilizations. The history of the area consisted of glorious battles, heroic acts, and the rise and fall of great civilizations. But, sometimes, natural hazards became the cause for a new classification of the political, as well as of the military status quo of the region. The enormous eruption of the submarine volcano at the Greek island of Thera (Santorini) during the Bronze Age, around 1500 BC, is such a natural hazard. The tsunami generated by the eruption, literally wiped out the peace-loving Minoan civilization who inhabited the island of Crete. After the sea subsided, the configuration of the area was altered, and the decline of the Minoan principality on the Archipelago began. The present paper introduces evidence concerning the tsunami and states some of the after-effects which were partly responsible for the decline of the Minoan empire. All the information is gathered from historical sources and from recent research works. An effort has been made to include many of the theories introduced by various researchers through time concerning the event. Finally, information has been included from all known research, as well as from the author's own conclusions, in order to make the paper useful to future researchers.
- Published
- 1992
29. A Robust Gaussian variogram estimator for cartography of hydrological extreme events
- Author
-
Alfonso Gutierrez-Lopez
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,0211 other engineering and technologies ,Estimator ,02 engineering and technology ,Geostatistics ,01 natural sciences ,Multivariate interpolation ,Moment (mathematics) ,Kriging ,Earth and Planetary Sciences (miscellaneous) ,Kurtosis ,Extreme value theory ,Variogram ,Cartography ,0105 earth and related environmental sciences ,Water Science and Technology ,Mathematics - Abstract
Kriging is used for spatial interpolation of geophysical and hydrological variables. This technique requires the definition of a mathematical function of spatial correlation known as variogram. Extreme value mapping is critical for the analysis of hydrological problems such as multiple risk and disaster damage valuation. However, the formulation of a variogram is complex and the selection of the variogram model is often crucial in the final representation of extreme values. There is some evidence that a variogram estimator may reduce the negative impact of using data samples with outliers. This is an approach that eliminates the term that takes into consideration the squared differences of empirical values in the calculation of a variogram. Known as Cressie–Hawkins Estimator (CH), it is based on considering a Gaussian distribution for the calculation of the variogram. The CH satisfies the main statistical considerations of normality; however, the formulation of kurtosis is not used to guarantee total normality. The present paper modifies the CH, adding the term corresponding to the fourth statistical moment. The numerical example proposed in the literature to evaluate the efficiency of the CH is reproduced, and it is verified that the new variogram (CH-GLo) decreases further the effect of the extreme values in the cartography. CH-GLo is applied to cartography an extreme storm that happened in August 2014 in the city of Queretaro, Mexico. It is concluded that this new variogram formulation is a suitable alternative for mapping extreme values monitored in real-time in urban areas.
- Published
- 2021
30. The application of DInSAR and Bayesian statistics for the assessment of landslide susceptibility
- Author
-
Dimitris Kouhartsiouk and Skevi Perdikou
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,Hydrogeology ,010504 meteorology & atmospheric sciences ,GNSS augmentation ,0211 other engineering and technologies ,Landslide ,02 engineering and technology ,computer.file_format ,Vegetation ,01 natural sciences ,Bayesian statistics ,Natural hazard ,Interferometric synthetic aperture radar ,Earth and Planetary Sciences (miscellaneous) ,Raster graphics ,computer ,Cartography ,Geology ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
The use of an inventory map of past landslide events in the derivation of susceptibility models is considered common practice. However, evidence of landslide activity may be lost due to various degrees of modification by subsequent landslides, erosional processes, vegetation growth and anthropic influences. The timely detection of active landslides can form an effective supplement to landslide records for improving the accuracy of landslide susceptibility maps. In this paper, we present a landslide susceptibility assessment carried out in a southwestern region of Cyprus using a synergy of differential interferometry and evidential statistics. A measurement of the vertical and horizontal displacements for the period 2016–2018 was done using the Small BAseline Subset multi-pass Differential Interferometric Synthetic Aperture Radar technique. Based on the results, a total of 8859 raster cells/pixels were classified as active landslides. The weight-of-evidence technique was applied to determine the weights of seven geomorphological and hydrological factors to landslide occurrence and compile a susceptibility model. The success and prediction rates of the derived model were calculated as 79.6% and 78.9%, respectively. The validation of the results against the existing landslide inventory indicates an 84% agreement with respect to the moderate and high landslide susceptibility zones. The proposed methodology can complement existing conventional landslide inventories as a means of providing updated landslide activity at frequent intervals and can provide valuable information regarding the distribution of landslides to support a detailed landslide assessment.
- Published
- 2021
31. Mapping the variability of carbonation progress using GIS techniques and field data: a case study of the Limassol district.
- Author
-
Tantele, Elia, Votsis, Renos, Danezis, Chris, Anastasiou, Constantina, and Georgiou, Nikolas
- Subjects
GEOGRAPHIC information systems ,CARTOGRAPHY ,GEOGRAPHY ,MEASUREMENT of corrosion potential ,GEOGRAPHICAL location codes - Abstract
Carbonation-induced corrosion of the steel reinforcement is the major deterioration factor of the RC infrastructures in urban areas. Carbonation progress in concrete is influenced by the exposure and environmental conditions prevailing at each area. Therefore, the rate of deterioration due to carbonation varies at different areas. Field measurements can quantify this carbonation progress for specific structures and areas. However, the scattered nature of individual field data offers little information to be considered for the assessment of existing structures or the design of new structures. This study aims to bridge this gap and shows that individual field data can be combined to characterise an area using GIS mapping tools. A generated map can depict the variability of carbonation progress with the geographical location. Measurements of the carbonation depth of several buildings at different locations in the Limassol district have been provided by a construction laboratory. Such information can be used to depict the carbonation progress on each structure through the calculation of the carbonation factor and then portray its value using mapping techniques. The result is a corrosion risk map of the Limassol district depicting the variability of carbonation progress with geographical locations. This can be used by engineers and managing authorities as a prediction tool for the initiation of carbonation-induced corrosion in existing structures and also at design stage to set the durability requirements of the concrete cover depth. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
32. Landslide susceptibility zonation mapping using frequency ratio and fuzzy gamma operator models in part of NH-39, Manipur, India.
- Author
-
Balamurugan, Guru, Ramesh, Veerappan, and Touthang, Mangminlen
- Subjects
LANDSLIDE hazard analysis ,LANDSLIDE prediction ,CARTOGRAPHY ,GEOMATICS ,TILLAGE ,REMOTE sensing - Abstract
The hilly region of Manipur especially along the NH-39 road, which is the lifeline of the State, is prone to landslides every year particularly during the monsoon season. Anthropological factors, such as excessive deforestation, unsystematic changes in land use and land cover pattern and slope cultivation, etc. are indirectly initiate the process of landslides. In the present study, landslide susceptibility mapping was carried out using frequency ratio and fuzzy gamma operator models with the help of geomatics techniques. The landslide susceptibility mapping was prepared using landslide inventory data and nine landslide causative factors, i.e. lithology, land use and land cover, geomorphology, drainage density, lineament density, slope gradient, slope aspect, curvature, and elevation. These causative factors were prepared with the help of toposheet, high resolution IRS P6 LISS IV satellite imagery, cartosat DEM data and extensive field work. The landslide susceptibility maps were prepared by calculating the relationship between the landslide causative parameters with landslide areas using a frequency ratio model. To get the fuzzy membership values, the frequency ratio values were normalized between the ranges of 0 and 1. The landslide susceptibility maps were compared and prediction accuracy of both the models was derived using the area under curve (AUC) method. The success rate curves were obtained using both training and all landslide inventory dataset. For training landslide inventory dataset, the AUC value of the success rate curve for the frequency ratio model was found to be 0.8056, whereas for the fuzzy gamma operator (using γ = 0.99) model, it was calculated as 0.9150. In the case of all landslide inventory dataset, the AUC value of the success rate curve for the frequency ratio model and the fuzzy gamma operator model were 0.7921 and 0.8188, respectively. The landslide susceptibility index was also compared with the landslide validation inventory dataset to obtain the prediction rate curves. The AUC value of the prediction rate curve for the frequency ratio model was 0.5681, whereas in the case of the fuzzy gamma operator model, it was 0.6721. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. Mapping the susceptibility to landslides based on the deep belief network: a case study in Sichuan Province, China
- Author
-
Yange Li, Zhuolei He, Jie Dou, Zheng Han, Weidong Wang, and Jianling Huang
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,Artificial neural network ,business.industry ,Deep learning ,0211 other engineering and technologies ,Boltzmann machine ,Landslide ,02 engineering and technology ,Collinearity ,01 natural sciences ,Deep belief network ,Stochastic gradient descent ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Artificial intelligence ,business ,Cartography ,Geology ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
A dataset of landslides from Sichuan Province in China, containing 1551 historical individual landslides, is a result of two teams’ effort in the past few years to map the susceptibility to landslides. Considering complex internal relations among the triggering factors, logistic regression (LR) and shallow neural networks, such as back-propagation neural network (BPNN), are often limited. In this paper, we make a straightforward development that the deep belief network (DBN) based on deep learning technology is introduced to map the regional susceptibility to landslides. Seven factors with respect to geomorphology, geology and hydrology are considered and verified through the collinearity test. A DBN model containing three pre-trained layers of restricted Boltzmann machines by stochastic gradient descent method is configured to obtain the susceptibility to landslides. Susceptibility results evaluated by DBN model are compared with those by LR and BPNN in the receive operator characteristic (ROC) analysis, showing that DBN has a better prediction precision, with a lower rate of false alarms and fake alarms. The case study also indicates different sensitivities of the triggering factors to the landslide susceptibility, that the factors of altitude, distance to drainage network and average annual rainfall have significant impact in mapping the susceptibility to landslides in the region. This research will contribute to a better-performance model for regional-scale mapping for the susceptibility to landslides, in particular, at the area where triggering factors show complex relations and relative independence.
- Published
- 2020
34. Multicriteria analysis applied to landslide susceptibility mapping.
- Author
-
Lorentz, Juliana, Calijuri, Maria, Marques, Eduardo, and Baptista, Alessandra
- Subjects
LANDSLIDES ,BODIES of water ,RURALIZATION ,POPULATION ,CARTOGRAPHY - Abstract
Current human settlements are characterized by disorganized urbanization and high population densities, which can impact the landscape and the environment. Soil transport leads to erosion and aggradation of water bodies and increases landslide susceptibility in regions with more uneven topographies. Landslides are the most common environmental accidents and have caused the most deaths; one example is the incident that occurred in the mountainous region of the state of Rio de Janeiro (Brazil) in January 2011. Mapping the predisposition or susceptibility of components of the physical environment to landslides provides an integrated view of the characteristics and physical processes that act within a region. Therefore, the objective of this study is to evaluate the urban expansion proposal of Baptista (Avaliação da suscetibilidade aos movimentos de massa, erosão e escoamento superficial em Nova Friburgo, RJ, ) and compare it with the areas affected by the mega-disaster of 2011 using hierarchical decision analysis and a GIS toolkit. The results show that landslides did not affect the areas selected for urban expansion, i.e., the method was useful for identifying the areas that were most susceptible to landslides prior to the disaster. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
35. Gas leakage hazard zonation of Masjed-i-Soleiman area, Zagros, Iran, using GiT.
- Author
-
Safari, Hojjat and Khedri-Gharibvand, Ladan
- Subjects
GAS leakage ,HAZARDS ,THRUST belts (Geology) ,GEOGRAPHIC information systems ,CARTOGRAPHY - Abstract
The shallow Masjed-i-Soleiman (MIS) oil field is situated at the Dezful Embayment in the Zagros Fold and Thrust Belt in southwestern Iran. The shallow depth of this oil field and multiple fractures has resulted in many gas leakages causing a significant pollution in residential areas around the area. In order to define the extent of the gas leakage, data sets such as surface structures, underground contour map, detected gas leakages, lithology, digital elevation models and population density were compiled using of remote sensing techniques and field investigations. The data were then added as layers in a geographic information system, which were overlaid form comparisons and used to construct a gas leakage hazard zonation map. This study shows that the central part of the MIS area, around the See-Berenj, Naftoon and Darre-Khersun districts, is a high-risk area, because of the shallow depth of gas caps, localizing of popular habitation and the high density of fractures and gas leakages. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
36. Detecting hydro-climatic change using spatiotemporal analysis of rainfall time series in Western Algeria.
- Author
-
Hamlaoui-Moulai, Leila, Mesbah, Mohammed, Souag-Gamane, Doudja, and Medjerab, Abderrahmane
- Subjects
CLIMATE change ,SPATIOTEMPORAL processes ,RAINFALL ,SPECTRUM analysis ,STATISTICS ,CARTOGRAPHY - Abstract
The knowledge of the climatic behavior especially that one of semi-arid regions is required to optimize the management of water resources. Here climate variability is directly related to water resources that are of a high socio-economic and environmental significance. This work deals mainly with a statistical analysis of the precipitation regime to assess its spatial distribution and temporal variation in north-western Algeria. For this, a time series and a principal component analysis are performed on rainfall series representing annual precipitations of twenty-one meteorological stations for the period 1914 to 2004, the most complete and longest of West Algeria, in order to detect patterns and trends in the region. A spectral analysis of the time series revealed the existence of a period of roughly 30 years for all stations. Furthermore, the trend of a wide part of the obtained spectra suggests the existence of another period longer than the samples size. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
37. Landslide susceptibility mapping using certainty factor, index of entropy and logistic regression models in GIS and their comparison at Mugling-Narayanghat road section in Nepal Himalaya.
- Author
-
Devkota, Krishna, Regmi, Amar, Pourghasemi, Hamid, Yoshida, Kohki, Pradhan, Biswajeet, Ryu, In, Dhital, Megh, and Althuwaynee, Omar
- Subjects
LANDSLIDES ,CARTOGRAPHY ,LOGISTIC regression analysis ,GEOGRAPHIC information systems - Abstract
Landslide susceptibility maps are vital for disaster management and for planning development activities in the mountainous country like Nepal. In the present study, landslide susceptibility assessment of Mugling-Narayanghat road and its surrounding area is made using bivariate (certainty factor and index of entropy) and multivariate (logistic regression) models. At first, a landslide inventory map was prepared using earlier reports and aerial photographs as well as by carrying out field survey. As a result, 321 landslides were mapped and out of which 241 (75 %) were randomly selected for building landslide susceptibility models, while the remaining 80 (25 %) were used for validating the models. The effectiveness of landslide susceptibility assessment using GIS and statistics is based on appropriate selection of the factors which play a dominant role in slope stability. In this case study, the following landslide conditioning factors were evaluated: slope gradient; slope aspect; altitude; plan curvature; lithology; land use; distance from faults, rivers and roads; topographic wetness index; stream power index; and sediment transport index. These factors were prepared from topographic map, drainage map, road map, and the geological map. Finally, the validation of landslide susceptibility map was carried out using receiver operating characteristic (ROC) curves. The ROC plot estimation results showed that the susceptibility map using index of entropy model with AUC value of 0.9016 has highest prediction accuracy of 90.16 %. Similarly, the susceptibility maps produced using logistic regression model and certainty factor model showed 86.29 and 83.57 % of prediction accuracy, respectively. Furthermore, the ROC plot showed that the success rate of all the three models performed more than 80 % accuracy (i.e. 89.15 % for IOE model, 89.10 % for LR model and 87.21 % for CF model). Hence, it is concluded that all the models employed in this study showed reasonably good accuracy in predicting the landslide susceptibility of Mugling-Narayanghat road section. These landslide susceptibility maps can be used for preliminary land use planning and hazard mitigation purpose. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
38. A site amplification factor map of the Iberian Peninsula and the Balearic Islands.
- Author
-
Núñez, Alberto, Rueda, Juan, and Mezcua, Julio
- Subjects
GEOLOGICAL mapping ,CARTOGRAPHY - Abstract
Considering the lack of site effect cartography in the Iberian Peninsula region to be related to the strong motion data, we present a site amplification factor map covering the Iberian Peninsula and the Balearic Islands. Steps leading to produce the map have included the classification of geological units from the 1:1,000,000 scale Geological Map of Spain into six site classes characterized on a seismic response basis, and the calculation, for every site class, of both short-period and mid-period amplification factors. In order to test the validity and applicability of the map, we have calculated the synthetic seismic intensity in the particular localities where several past earthquakes were felt, supposing a point source approximation. The synthetic intensities have been obtained with and without site amplification factors, resulting in two types of synthetic isoseismals maps that have been compared with the corresponding observed isoseismals. As the amplification factors obtained are only applicable to the linear domain, the synthetic intensities greater than VII are only illustrative. A main conclusion has been drawn about the fact that synthetic isoseismals with site amplification factor approach to the related observed isoseismals in a higher degree than synthetic isoseismals without site amplification factor. In addition, the resemblances between the synthetic isoseismals produced with site amplification factors and the corresponding observed isoseismals have been found to be more evident at shorter epicentral distances, provided that intensities are lower than VIII, and therefore, we remain in the linear domain. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
39. Development of python-FALL3D: a modified procedure for modelling volcanic ash dispersal in the Asia-Pacific region.
- Author
-
Bear-Crozier, A., Kartadinata, Nugraha, Heriwaseso, Anjar, and Nielsen, Ole
- Subjects
VOLCANIC ash, tuff, etc. ,HAZARD mitigation ,CARTOGRAPHY ,VOLCANIC activity prediction - Abstract
Volcanic ash is the most widespread of all volcanic hazards and has the potential to affect hundreds of thousands, or even millions, of people in the densely populated islands of Indonesia. There is limited information available for this region on the hazard posed by volcanic ash, particularly from volcanoes that have not erupted in recent times. There is a need for computational models capable of accurately predicting volcanic ash dispersal at ground level when coupled with field observations of historical or ongoing eruptive activity. To maximise the effectiveness of such models, they should be readily accessible, easy to use and well tested. Geoscience Australia in collaboration with the Australia-Indonesia Facility for Disaster Reduction and the Indonesian Centre for Volcanology and Geohazard Mitigation has collaboratively adapted an existing open-source volcanic ash dispersion model for use in Indonesia. The core model is the widely used, open-source volcanic ash dispersion model FALL3D. A Python wrapper (name here python-FALL3D) has been developed, which modifies the modelling procedure of FALL3D in order to simplify its use for those with little or no background in computational modelling. The modified procedure does not alter the core functionality of FALL3D, but simplifies the modelling procedure by streamlining the installation process, automating both the pre-processing of input meteorological datasets and configuring and executing each utility program in a single-step process. An application example was presented using python-FALL3D for an active volcano in West Java, Indonesia. The example showed that communities located on the western side of Gunung Gede are always susceptible to volcanic ash ground loading regardless of the seasonal variations in wind conditions, whereas communities on the eastern side of Gunung Gede have a marked increase in susceptibility to ground loading during rainy season conditions when prevailing winds include a strong easterly component. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
40. Changes in coastal land use and the reasons for selecting places to live in Banda Aceh 10 years after the 2004 Indian Ocean tsunami
- Author
-
Syamsidik, Suhada Arief, Inayah Zhiaul Fajri, Rina Suryani Oktari, and Khairul Munadi
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Population ,0211 other engineering and technologies ,02 engineering and technology ,01 natural sciences ,Human settlement ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Natural disaster ,education ,0105 earth and related environmental sciences ,Water Science and Technology ,media_common ,021110 strategic, defence & security studies ,education.field_of_study ,Land use ,Emergency management ,business.industry ,Environmental resource management ,Economic rent ,Geography ,Work (electrical) ,business ,Cartography - Abstract
Ten years after the Indian Ocean tsunami in 2004 and following a long process of rehabilitation and reconstruction, Aceh has finally recovered. After the tsunami, Aceh experienced a dramatic migration of its coastal population away from the city; however, after 10 years, the population has mostly recovered. As new houses have been built and new economic activities commenced in the coastal areas, there is now concern regarding potential future tsunami risks for the city. The initial rehabilitation and reconstruction plan sought to prevent the construction of any new houses 500 m from the coastline; however, this failed to happen. This paper elucidates the reasons why these new coastal communities chose their new housing areas and examines the coastal land use changes around Banda Aceh 10 years after the Indian Ocean tsunami. Questionnaires were distributed to 457 respondents, and multiple logistic regressions were used to examine the reasons for household location selection and whether a possible future tsunami was a deciding factor. To examine the coastal land use changes, a series of aerial images from the Banda Aceh coastal area were digitised. It was found that tsunami history was not a major factor in new household selection; rather, rents and land prices, distance from work, and family connections were the top three reasons motivating households to select new living places. These changes and new settlements have given the city’s disaster management agency the challenge of building more emergency infrastructure in the coastal areas.
- Published
- 2017
41. Policy and systems of flood risk management: a comparative study between Japan and Spain
- Author
-
Isao Nakamura, Maria Carmen Llasat, and Universitat de Barcelona
- Subjects
Atmospheric Science ,Flood warning ,Catalonia ,010504 meteorology & atmospheric sciences ,Tokyo (Japan) ,Population ,0211 other engineering and technologies ,02 engineering and technology ,01 natural sciences ,Control d'inundacions ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Tòquio (Japó) ,education ,Socioeconomics ,0105 earth and related environmental sciences ,Water Science and Technology ,021110 strategic, defence & security studies ,education.field_of_study ,Flood myth ,Emergency management ,business.industry ,Catalunya ,Hazard ,Floods ,Flood control ,Risk perception ,Geography ,Inundacions ,Flood insurance ,business ,Cartography - Abstract
This paper shows a comparison from the perspective of flood risk management between two regions of different countries: Tokyo Metropolis (Japan) and Catalonia (Spain). The comparison is based on flood damage data for a 30-year period (1981-2010), legislation, disaster management plans, recovering measures, and communication strategies. A total of 219 flood events and 110 deaths were recorded in Catalonia during 1981-2010, while there were 191 floods in Tokyo, during the same period, giving place to 27 deaths and missing people. In both countries, most of the deaths occurred outdoors and the majority as a consequence of imprudent behavior. Nearly 10% of flood victims in Catalonia were foreign citizens. Regarding the institutions from the state and the communities involved in flood risk management, we have found a similar structure between the two countries. In accordance with the European Floods Directive, all the Spanish regions susceptible of having floods have flood hazard maps for different return periods, including 500 years while in the case of Japan the return periods are usually shorter. Recently, flood risk maps have been built for Catalonia, but none is available in a foreign language. Although all the maps are available in Internet, in Spain it is not mandatory to distribute maps to the public neither evacuation maps in flood-prone areas. On the contrary, evacuation and hazard maps in Japan have some parts written in different languages. In both countries, flood hazard maps are not compulsorily linked to other countermeasures such as land-use regulation (the municipality has the last decision) or flood insurance. Thresholds of heavy rain warnings are similar in both countries, using rain amounts over both short and long periods. Although the Japanese method appears more sophisticated using humidity and runoff indexes, it is too complicated for people to understand it. In contrast, only Catalonia has forecast thresholds considering probability levels. On flood insurance, only Spain has governmental aid to the flood insurance system. The level of flood risk perception is low among the population in both countries, and social communication for flood risk is insufficient, mainly in Catalonia. Thus, it is very important that individuals recognize the flood risk in the area to reduce the number of victims.
- Published
- 2017
42. Assessment and mapping of earthquake-induced landslides in Tigzirt City, Algeria
- Author
-
Nassima Alimrina, Ramdane Bahar, Bachir Melbouci, Lynda Djerbal, and Ibtissam Khoudi
- Subjects
Risk analysis ,Atmospheric Science ,Geographic information system ,010504 meteorology & atmospheric sciences ,business.industry ,Urban density ,Landslide ,Context (language use) ,Induced seismicity ,010502 geochemistry & geophysics ,01 natural sciences ,Hazard ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,business ,Cartography ,Seismology ,Geology ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
The natural hazard assessment is hampered by many difficulties due to the complexity of the phenomenon and the need to manage simultaneously several natural and/or technological hazards. Such is the case of most unstable urban sites in Algeria. The paper presents a risk analysis study of landslides and their reactivation in Tigzirt coastal city, located in the north of Algeria, which is classified in a moderate seismic zone. The spatial techniques based on geographic information systems are used to assess landslide susceptibility and hazard. Two qualitative studies of landslide hazard assessment are conducted using parameters defining the Algerian landslides context. The hazard is evaluated by performing a combination of the landslide susceptibility and the urban density. Earthquake-induced landslide hazard is assessed taking into account the Algerian seismicity. The study led to determination and mapping of the hazard induced by Tigzirt landslides.
- Published
- 2017
43. Seismic risk assessment and mapping at different levels
- Author
-
S. P. Sushchev, Jean Bonnin, A. N. Ugarov, Nina Frolova, M. A. Kozlov, and Valery Larionov
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,0211 other engineering and technologies ,Vulnerability ,02 engineering and technology ,Induced seismicity ,01 natural sciences ,Geography ,Natural hazard ,Scale (social sciences) ,Earth and Planetary Sciences (miscellaneous) ,Russian federation ,Seismic risk ,Risk assessment ,Cartography ,Built environment ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Earthquakes incur the greatest damage compared with all the other natural deleterious occurrences; when occurring in industrialized and densely populated regions, they can prove devastating. In the Russian Federation, we have more than 20 million people living in regions of moderate and high seismicity. The areas that are hit by earthquakes, with events of intensity VII (MMSK-86 scale) or greater occurring, make up approximately 20% of Russia’s area. The present paper addresses the methodological procedures of risk assessment and databases used for risk computations at different levels. The examples of seismic risk assessment and mapping at different levels: country, region and urban, are given. Special attention is paid to information and web technologies used for verification data on built environment inventory and vulnerability.
- Published
- 2016
44. A new hybrid procedure for the definition of seismic vulnerability in Mediterranean cross-border urban areas
- Author
-
M.F. Ferrotto, Fabio Di Trapani, Liborio Cavaleri, Cavaleri, L., Di Trapani, F., and Ferrotto, M.
- Subjects
Atmospheric Science ,Peak ground acceleration ,Index (economics) ,Vulnerability index ,0211 other engineering and technologies ,Vulnerability ,020101 civil engineering ,02 engineering and technology ,0201 civil engineering ,Seismic risk ,Natural hazard ,Vulnerability curve ,Earth and Planetary Sciences (miscellaneous) ,Duration (project management) ,Masonry ,Water Science and Technology ,Estimation ,021110 strategic, defence & security studies ,Pushover ,business.industry ,PGA ,Environmental resource management ,Vulnerability curves ,Settore ICAR/09 - Tecnica Delle Costruzioni ,business ,Cartography - Abstract
Assessment of seismic vulnerability of urban areas provides fundamental information for activities of planning and management of emergencies. The main difficulty encountered when extending vulnerability evaluations to urban contexts is the definition of a framework of assessment appropriate for the specific characteristics of the site and providing reliable results with a reasonable duration of surveys and post-processing of data. The paper proposes a new procedure merging different typologies of information recognized on the territories investigated and for this reason called “hybrid.” Knowledge of historical events influencing urban evolution and analysis of recurrent building technologies are used to evaluate the vulnerability indexes of buildings and building stocks. On the other hand, a vulnerability model is calibrated by means of experimental and numerical investigations on prototype buildings representative of the most recurrent typologies. In the final framework, the vulnerability index, calculated through simplified assessment forms, is linked to the seismic intensity expressed by the peak ground acceleration and associated with an index of damage expressing the economical loss. The procedure has been tested on the urban center of Lampedusa island (Italy) providing as the output vulnerability index maps, vulnerability curves, critical PGA maps, and estimation of the economical damage associated with different earthquake scenarios. The application of the procedure can be suitably repeated for medium-to-small urban areas, typically recurring in the Mediterranean by carrying out each time a recalibration of the vulnerability model.
- Published
- 2016
45. An analysis of methods for identifying social vulnerability to climate change and sea level rise: a case study of Hampton Roads, Virginia
- Author
-
Jeremy Abramowitz and Sarah L. Stafford
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,business.industry ,media_common.quotation_subject ,Search engine indexing ,Environmental resource management ,0211 other engineering and technologies ,Vulnerability ,02 engineering and technology ,01 natural sciences ,Geography ,Natural hazard ,Principal component analysis ,Earth and Planetary Sciences (miscellaneous) ,Psychological resilience ,business ,Cluster analysis ,Cartography ,Social vulnerability ,Strengths and weaknesses ,0105 earth and related environmental sciences ,Water Science and Technology ,media_common - Abstract
This paper examines methods for quantitatively identifying communities that have high social vulnerability to environmental hazards. We first provide an overview of the existing literature on quantifying social vulnerability. We discuss the strengths and weaknesses of the one of the most common methods, composite indexing using principal component analysis (PCA), in more detail. We present a case study of Hampton Roads, Virginia, that compares PCA-based composite indexing to an alternative method using k-means clustering to identify socially vulnerable communities. We find that PCA-based indexing is particularly sensitive to changes in geographic boundaries and the number of input variables while clustering is less so. However, both methods exhibit the highest levels of consistency when vulnerability is measured by a relatively small number of well-established quantitative indicators. While the cluster method is more intuitive and easier to interpret than composite indexing, it is not well suited for large analyses across a disparate geographic area or where one needs to explicitly rank observations.
- Published
- 2016
46. Measuring the vulnerability of disadvantaged populations during hurricane evacuation
- Author
-
Chester G. Wilmot and Ruijie Bian
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,education.field_of_study ,010504 meteorology & atmospheric sciences ,Land use ,Population ,0211 other engineering and technologies ,Vulnerability ,Regression analysis ,02 engineering and technology ,Land cover ,Census ,01 natural sciences ,Geography ,Dasymetric map ,Earth and Planetary Sciences (miscellaneous) ,Hurricane evacuation ,education ,Cartography ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
In this paper, the extent to which the potentially transit-dependent portion of the population is vulnerable to the effects of a hurricane is estimated. The vulnerability of an area is defined as a composite measure of the proportion of disadvantaged persons, distance to transit, and flooding potential of people within an area. Unlike past studies which have focused on the vulnerability of the population in relatively large geographic areas, this study estimates the vulnerability of the population in 30 m × 30 m areas as defined in the National Land Cover Database. Population estimates from the national census at block level are disaggregated to the 30 m × 30 m units using a modified dasymetric mapping method in ArcGIS. The modified mapping method assigns population to each small areal unit using weights estimated by regressing the area of each land use in a census block against the population in that block. The coefficients in the regression analysis are “weights” associating population with each land use, and are used to distribute the population in each census block to the small geographic units based on their land use. In a case study of New Orleans, the results show that some areas are not well served by the existing transit pickup locations, as evidenced by their high vulnerability scores. Reassignment of pickup point locations to cover higher vulnerability score areas was investigated using integer linear programming. The results show that the optimally located pickup points serve areas with a larger average vulnerability score than the current pickup points in the study area. The method appears to be helpful in identifying vulnerable areas that, subsequently, could receive improved hurricane evacuation service in the future.
- Published
- 2016
47. Recent changes of extreme dryness/wetness pattern and its possible impact on rice productivity in Jiangsu Province, southeast China
- Author
-
Yan Xue, Jin Huang, Fangmin Zhang, and Qi Li
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,0208 environmental biotechnology ,02 engineering and technology ,01 natural sciences ,020801 environmental engineering ,Trend analysis ,Linear relationship ,Geography ,Productivity (ecology) ,Earth and Planetary Sciences (miscellaneous) ,medicine ,Dryness ,Physical geography ,Precipitation ,Negative correlation ,medicine.symptom ,Precipitation index ,China ,Cartography ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Based on the data of monthly precipitation and rice productivity at 61 meteorological stations in Jiangsu during 1966–2010, the possible impact of dryness/wetness variability on rice productivity was explored in this paper. Principal component analysis was applied to the climate-induced rice productivity index (CRPI) series and divided Jiangsu into six sub-regions—south, northwest, east, middle, southwest and northernmost. Mann–Kendall trend test for monthly Standardized Precipitation Index (SPI) series in each sub-regions shows that most of Jiangsu was dominated by wetter tendency in August and drier tendency in September. CRPI had stronger negative correlation with monthly SPI series in the majority of sub-regions. Especially, the SPI in October, March, July and August had significantly negative linear relationship with CRPI in south Jiangsu, northwest Jiangsu, middle Jiangsu and southwest Jiangsu, respectively, which indicated the obvious unfavourable impact of extreme wetness episodes on rice productivity.
- Published
- 2016
48. Use of GIS in assessing building vulnerability for landslide hazard in The Nilgiris, Western Ghats, India
- Author
-
Edison Thennavan, S. S. Chandra Sekaran, A. S. Rajawat, and G. P. Ganapathy
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,education.field_of_study ,Warning system ,Population ,0211 other engineering and technologies ,Vulnerability ,Landslide ,02 engineering and technology ,Hazard ,Thematic map ,Geography ,Vulnerability assessment ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,education ,Cartography ,021101 geological & geomatics engineering ,Water Science and Technology - Abstract
The present paper aims at to produce the building vulnerability and its spatial distribution in mountainous regions of the Nilgiris District in the Western Ghats, India. The landslide-susceptible areas were identified based on the existing landslide-susceptible maps. The landslide-prone slope was identified based on the historical and recent landslide information’s collected from various authenticated sources as well as the field investigations made on the recent landslides. The high-to-severe landslide hazard-prone areas were selected for the present study of building vulnerability analysis. The areas were divided into ten segments based on the landslide inventory, built-up areas, and transportation corridors in the vicinity of landslide locations. Building foot print map was prepared for each segments using ArcGIS software visual interpretation for 1627 buildings and infrastructures. Different thematic layers viz, building type/material, surrounding wall, sloping side details, warning, and number of floors which contribute to landslide vulnerability in vector formats are used for the present study. Using the formula proposed by Papathoma-Kohle et al. (Nat Hazards Earth Syst Sci 7:765–779, 2007) the vulnerability score were calculated by scripting in ArcGIS software. Based on the vulnerability score, the buildings were grouped under three categories viz, low, medium, and high vulnerability. The spatial distribution of vulnerability of buildings was prepared and presented. The present study can be useful data for preparation of regional landuse plan as well as evacuation plans and warning systems to safeguard measure for population living in the vulnerable buildings in The Nilgiris District of Western Ghats in India.
- Published
- 2016
49. Characterizing the multi-risk with respect to plausible natural hazards in the Balasore coast, Odisha, India: a multi-criteria analysis (MCA) appraisal
- Author
-
Sugata Hazra, Craig W. Hutton, D. Mitra, Anirban Mukhopadhyay, Abhra Chanda, and Sandip Mukherjee
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,education.field_of_study ,010504 meteorology & atmospheric sciences ,Population ,0211 other engineering and technologies ,Storm surge ,Urban density ,02 engineering and technology ,01 natural sciences ,Hazard ,Coastal erosion ,Geography ,Natural hazard ,BENGAL ,Earth and Planetary Sciences (miscellaneous) ,Physical geography ,Coastal flood ,education ,Cartography ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Coastal zones are often prone to several natural hazards, and where the coastal zone has high population density and infrastructural assets, these hazards can render severe loss to both life and properties. The present paper reports a comprehensive assessment of the multi-hazard and multi-risk (keeping in view the population and assets exposed to multi-hazards) in the Balasore coast, situated in the state of Odisha, India, facing the Bay of Bengal immediately to its east. In most of the multi-hazard and multi-risk assessments, the importance of any one hazard in relation to others is often determined arbitrarily. To overcome this limitation, this work presents a multi-criteria analysis implemented on six hazards, namely coastal erosion, storm surge, sea level rise, coastal flooding, tsunami, and earthquake. The respective hazards were ranked according to their relative weight computed by pair-wise comparison, and the overall multi-hazard map of the coast was prepared using weighted overlay technique in GIS environment. In order to assess the exposure, population density and urban assets of the study area were also mapped. Finally, the population and urban density data were overlain on the multi-hazard map in order to derive the final map portraying the multi-risk of the Balasore coast. Coastal erosion and storm surge inundation are the two most substantial natural hazards that regularly affect this coast. It is also observed that hazard from the perspective of coastal erosion is spatially concentrated along the central part of the coast, while in the southern part, the effect of storm surge is higher. The area in and around Chandipur, which is situated in the central portion of the Balasore coast, has been found to have the highest multi-risk, which also happens to be a popular tourist destination.
- Published
- 2015
50. Normalized Landslide Index Method for susceptibility map development in El Salvador
- Author
-
Konstantine P. Georgakakos and Ari Posner
- Subjects
Atmospheric Science ,Geography ,Bivariate data ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Analytic hierarchy process ,Landslide ,Bivariate analysis ,Landslide susceptibility ,Cartography ,Water Science and Technology ,Index method - Abstract
El Salvador and Central America in general are highly prone to landsliding. In November 1998, Hurricane Mitch killed 240 people, displaced about 85,000 people, caused more than $600 million in economic losses, and damaged about 60 % of the nation’s roads (Rose et al. in Natural hazards in El Salvador. Geologic Society of America of special paper 375, Boulder, 2004). An understanding of susceptibility of locations to landsliding is critical for development and mitigation planning. This work presents the development of the Normalized Landslide Index Method which is a derivative of the bivariate statistical methods commonly used in landslide susceptibility assessment. The resultant map was amended through a tangential analysis, also commonly used in landslide susceptibility mapping, the Analytical Hierarchy Process (AHP), which reduces multi-criteria analysis to pair-wise comparisons. The assimilation of results from the AHP analysis into the statistically derived susceptibility map skewed the original results by emphasizing the extremes already found. It was determined that addition of AHP results did not increase the value of the derived susceptibility map. Finally, a physically based a priori approach to landslide susceptibility mapping, developed by El Salvador National Service of Territorial Studies, was compared to the statistically derived map developed herein. It was found that the a priori approach was not sufficiently discriminant to be useful for planners and regulators, as very large areas were designated high susceptibility that included areas with low slope angles. The development of the normalized landslide index is a significant improvement to the class of bivariate statistical strategies to assess regional landslide susceptibility.
- Published
- 2015
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.