GIS- and RS-Based Modelling of Potential Natural Hazard Areas in Mountains. Case Study: Vlahina Mountain

The use of 3D point clouds to improve the understanding of natural phenomena is currently applied in natural hazard investigations, including the quantification of rockfall activity. However, 3D point cloud treatment is typically accomplished using nondedicated (and not optimal) software. To fill this gap, we present an open-source, specific rockfall package in an object-oriented toolbox developed in the MATLAB® environment. The proposed package offers a complete and semiautomatic 3D solution that spans from extraction to identification and volume estimations of rockfall sources using state-of-the-art methods and newly implemented algorithms. To illustrate the capabilities of this package, we acquired a series of high-quality point clouds in a pilot study area referred to as the La Cornalle cliff (West Switzerland), obtained robust volume estimations at different volumetric scales, and derived rockfall magnitude–frequency distributions, which assisted in the assessment of rockfall activity and long-term erosion rates. An outcome of the case study shows the influence of the volume computation on the magnitude–frequency distribution and ensuing erosion process interpretation.

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An Input–Output Ex Ante Regional Model to Assess the Short-Term Net Effects of the 16 April 2016 Earthquake in Ecuador

International Journal of Disaster Risk Science ◽

10.1007/s13753-021-00354-6 ◽

2021 ◽

Author(s):

Jorge Salgado ◽

José Ramírez-Álvarez ◽

Diego Mancheno

Keyword(s):

Natural Hazard ◽

National Accounts ◽

Input Output ◽

Short Term ◽

Ex Ante ◽

The Impact ◽

Consumption Demand ◽

Two Sectors ◽

Positive Effect

AbstractThe 16 April 2016 earthquake in Ecuador exposed the significant weaknesses concerning the methodological designs to compute—from an economic standpoint—the consequences of a natural hazard-related disaster for productive exchanges and the accumulation of capital in Ecuador. This study addressed one of these challenges with an innovative ex ante model to measure the partial and net short-term effects of a natural hazard-related catastrophe from an interregional perspective, with the 16 April 2016 earthquake serving as a case study. In general, the specified and estimated model follows the approach of the extended Miyazawa model, which endogenizes consumption demand in a standard input–output model with the subnational interrelations and resulting multipliers. Due to the country’s limitations in its regional account records the input–output matrices for each province of Ecuador had to be estimated, which then allowed transactions carried out between any two sectors within or outside a given province to be identified by means of the RAS method. The estimations provide evidence that the net short-term impact on the national accounts was not significant, and under some of the simulated scenarios, based on the official information with respect to earthquake management, the impact may even have had a positive effect on the growth of the national product during 2016.

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Social Representations of Natural Hazard Risk in Swiss Mountain Regions

Geosciences ◽

10.3390/geosciences9010002 ◽

2018 ◽

Vol 9 (1) ◽

pp. 2

Author(s):

Elisabeth Maidl ◽

Matthias Buchecker

Keyword(s):

Risk Communication ◽

Natural Hazard ◽

Qualitative Case Study ◽

Social Representations ◽

Case Study Research ◽

Community Size ◽

Hazard Risk ◽

Risk Research ◽

Hazard Experience

The term “risk” is connoted with divergent meanings in natural hazard risk research and the practice of risk management. Whilst the technical definition is accurately defined, in practice, the term “risk” is often synonymously used with “danger”. Considering this divergence as a deficiency, risk communication often aims to correct laypersons’ understanding. We suggest to instead treat the variety of meanings as a resource for risk communication strategies. However, there is however to date no investigation of what laypersons’ meanings of risk actually comprise. To address this gap, we examine the meanings of risk by applying a social representations approach within a qualitative case study research design. Results of the study among inhabitants of Swiss mountain villages show that differences in meanings were found according to hazard experience and community size. We found commonly shared core representations and peripheral ones. We conclude with suggestions on how to make usage of the knowledge on SR in risk communication.

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