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Nicolas Villeneuve - One of the best experts on this subject based on the ideXlab platform.
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Newspaper reporting of the April 2007 eruption of Piton de la Fournaise, part 2: framing the Hazard
Journal of Applied Volcanology, 2018Co-Authors: Andrew J. L. Harris, Nicolas VilleneuveAbstract:An analysis of the front pages of 120 consecutive editions of the local newspaper for the island of La Réunion (France), “Le Journal de L’Ile de La Réunion”, published before, during and after the April 2007 eruption of Piton de la Fournaise reveals that its front page is an ideal vehicle for maximizing information delivery and recall during a volcanic eruption. Supported by flash tests, and by cross-checking with a content analysis of information given within the newspaper, we find that the front page is an effective gauge for the Hazard frame which, for the case examined here, involved six volcanic Hazards (pit-crater collapse, lava flows, gas, air Fall, ocean entry lava flow and bench collapse), as well as the issue of evacuation. We found that crater collapse and lava flow Hazards were framed using their natural colors and clear imagery of the phenomenon, tied to context-setting explanations within the newspaper. However, for lava flows in particular there was an element of spectacle and promotion of sightseeing, with photographs always featuring sightseers invariably taking photographs. After the end of the eruption reporting became almost entirely focused on tourists and sightseeing. Gas and ash Fall Hazard were framed using images and words of the victims, so that it became worrying and frightening, and associated with panic. As a result, the volcano itself became portrayed as a monster, and the situation for the impacted population became “apocalyptic” and “hellish”. This probably contributed to the evacuation measures being described as confused and pointless, with the morale of the impacted population suffering accordingly. The ocean entry and bench collapse had no frame at all, and became associated with the dead, exotic fish that were collected; this Hazard thus being framed as an interesting curiosity rather than a volcanic Hazard. The front page-tracking model followed here could guide future educative measures during volcanic crises by quickly identifying, on the basis of front page analysis, Hazards that are appropriately conveyed versus those that are poorly portrayed. Responses to rectify a poor frame can include reactive scientific advertising, a route that is used commonly by businesses seeking to boost sales by taking timely advantage of a developing newspaper frame, and distribution of appropriately designed and timed press releases.
Andrew J. L. Harris - One of the best experts on this subject based on the ideXlab platform.
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Newspaper reporting of the April 2007 eruption of Piton de la Fournaise, part 2: framing the Hazard
Journal of Applied Volcanology, 2018Co-Authors: Andrew J. L. Harris, Nicolas VilleneuveAbstract:An analysis of the front pages of 120 consecutive editions of the local newspaper for the island of La Réunion (France), “Le Journal de L’Ile de La Réunion”, published before, during and after the April 2007 eruption of Piton de la Fournaise reveals that its front page is an ideal vehicle for maximizing information delivery and recall during a volcanic eruption. Supported by flash tests, and by cross-checking with a content analysis of information given within the newspaper, we find that the front page is an effective gauge for the Hazard frame which, for the case examined here, involved six volcanic Hazards (pit-crater collapse, lava flows, gas, air Fall, ocean entry lava flow and bench collapse), as well as the issue of evacuation. We found that crater collapse and lava flow Hazards were framed using their natural colors and clear imagery of the phenomenon, tied to context-setting explanations within the newspaper. However, for lava flows in particular there was an element of spectacle and promotion of sightseeing, with photographs always featuring sightseers invariably taking photographs. After the end of the eruption reporting became almost entirely focused on tourists and sightseeing. Gas and ash Fall Hazard were framed using images and words of the victims, so that it became worrying and frightening, and associated with panic. As a result, the volcano itself became portrayed as a monster, and the situation for the impacted population became “apocalyptic” and “hellish”. This probably contributed to the evacuation measures being described as confused and pointless, with the morale of the impacted population suffering accordingly. The ocean entry and bench collapse had no frame at all, and became associated with the dead, exotic fish that were collected; this Hazard thus being framed as an interesting curiosity rather than a volcanic Hazard. The front page-tracking model followed here could guide future educative measures during volcanic crises by quickly identifying, on the basis of front page analysis, Hazards that are appropriately conveyed versus those that are poorly portrayed. Responses to rectify a poor frame can include reactive scientific advertising, a route that is used commonly by businesses seeking to boost sales by taking timely advantage of a developing newspaper frame, and distribution of appropriately designed and timed press releases.
H S Duzgun - One of the best experts on this subject based on the ideXlab platform.
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analysis of roof Fall Hazards and risk assessment for zonguldak coal basin underground mines
International Journal of Coal Geology, 2005Co-Authors: H S DuzgunAbstract:The roof Fall Hazards are frequent problems of underground coal mines, which are generally unpredictable due to the associated uncertainties. These uncertainties, which arise from geological and stress conditions and mine environment, make the control of roof Fall Hazards difficult in underground coal mines. The most efficient method for coping with uncertainties in roof Fall Hazards is the use of risk assessment techniques. In this study, a risk assessment and management methodology is proposed for roof Fall Hazards in underground mines of the Zonguldak coal basin. The annual rates of roof Falls obtained from the five mines in the basin are statistically analyzed. The components of risk, which are the probability of roof Fall and consequences of roof Fall Hazard are identified and quantified. The probability of roof Fall is computed by fitting a distribution function to the annual roof Fall, while the consequences of roof Falls are quantified based on a cost model. Then a decision analysis methodology for evaluating the performance of possible alternative action to be taken in order to decrease the risk, is developed. The results show that the underground coal mines in the Zonguldak coal basin have considerably high risk levels and hence require comprehensive risk management schemes.
Villeneuve Nicolas - One of the best experts on this subject based on the ideXlab platform.
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Newspaper reporting of the April 2007 eruption of Piton de la Fournaise, part 2: framing the Hazard
'Springer Science and Business Media LLC', 2018Co-Authors: Harris Andrew, Villeneuve NicolasAbstract:International audienceAn analysis of the front pages of 120 consecutive editions of the local newspaper for the island of La Réunion (France), “Le Journal de L’Ile de La Réunion”, published before, during and after the April 2007 eruption of Piton de la Fournaise reveals that its front page is an ideal vehicle for maximizing information delivery and recall during a volcanic eruption. Supported by flash tests, and by cross-checking with a content analysis of information given within the newspaper, we find that the front page is an effective gauge for the Hazard frame which, for the case examined here, involved six volcanic Hazards (pit-crater collapse, lava flows, gas, air Fall, ocean entry lava flow and bench collapse), as well as the issue of evacuation. We found that crater collapse and lava flow Hazards were framed using their natural colors and clear imagery of the phenomenon, tied to context-setting explanations within the newspaper. However, for lava flows in particular there was an element of spectacle and promotion of sightseeing, with photographs always featuring sightseers invariably taking photographs. After the end of the eruption reporting became almost entirely focused on tourists and sightseeing. Gas and ash Fall Hazard were framed using images and words of the victims, so that it became worrying and frightening, and associated with panic. As a result, the volcano itself became portrayed as a monster, and the situation for the impacted population became “apocalyptic” and “hellish”. This probably contributed to the evacuation measures being described as confused and pointless, with the morale of the impacted population suffering accordingly. The ocean entry and bench collapse had no frame at all, and became associated with the dead, exotic fish that were collected; this Hazard thus being framed as an interesting curiosity rather than a volcanic Hazard. The front page-tracking model followed here could guide future educative measures during volcanic crises by quickly identifying, on the basis of front page analysis, Hazards that are appropriately conveyed versus those that are poorly portrayed. Responses to rectify a poor frame can include reactive scientific advertising, a route that is used commonly by businesses seeking to boost sales by taking timely advantage of a developing newspaper frame, and distribution of appropriately designed and timed press releases
Fausto Guzzetti - One of the best experts on this subject based on the ideXlab platform.
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rockFall Hazard and risk assessment in the yosemite valley california usa
Natural Hazards and Earth System Sciences, 2003Co-Authors: Fausto Guzzetti, Paola Reichenbach, G F WieczorekAbstract:Abstract. Rock slides and rock Falls are the most frequent types of slope movements in Yosemite National Park, California. In historical time (1857–2002) 392 rock Falls and rock slides have been documented in the valley, and some of them have been mapped in detail. We present the results of an attempt to assess rock Fall Hazards in the Yosemite Valley. Spatial and temporal aspects of rock Falls Hazard are considered. A detailed inventory of slope movements covering the 145-year period from 1857 to 2002 is used to determine the frequency-volume statistics of rock Falls and to estimate the annual frequency of rock Falls, providing the temporal component of rock Fall Hazard. The extent of the areas potentially subject to rock Fall Hazards in the Yosemite Valley were obtained using STONE, a physically-based rock Fall simulation computer program. The software computes 3-dimensional rock Fall trajectories starting from a digital elevation model (DEM), the location of rock Fall release points, and maps of the dynamic rolling friction coefficient and of the coefficients of normal and tangential energy restitution. For each DEM cell the software calculates the number of rock Falls passing through the cell, the maximum rock Fall velocity and the maximum flying height. For the Yosemite Valley, a DEM with a ground resolution of 10 × 10 m was prepared using topographic contour lines from the U.S. Geological Survey 1:24 000-scale maps. Rock Fall release points were identified as DEM cells having a slope steeper than 60 ° , an assumption based on the location of historical rock Falls. Maps of the normal and tangential energy restitution coefficients and of the rolling friction coefficient were produced from a surficial geologic map. The availability of historical rock Falls mapped in detail allowed us to check the computer program performance and to calibrate the model parameters. Visual and statistical comparison of the model results with the mapped rock Falls confirmed the accuracy of the model. The model results are compared with a previous map of rockFall talus and with a geomorphic assessment of rock Fall Hazard based on potential energy referred to as a shadow angle approach, recently completed for the Yosemite Valley. The model results are then used to identify the roads and trails more subject to rock Fall Hazard. Of the 166.5 km of roads and trails in the Yosemite Valley 31.2% were found to be potentially subject to rock Fall Hazard, of which 14% are subject to very high Hazard.
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stone a computer program for the three dimensional simulation of rock Falls
Computers & Geosciences, 2002Co-Authors: Fausto Guzzetti, Giovanni B Crosta, Riccardo Detti, F AgliardiAbstract:Rock-Fall poses a continuous Hazard in mountain areas worldwide. Despite the fact that rock Fall is a simple landslide type to model, only a few attempts have been made to establish rock-Fall Hazard and the associated risk at regional scales. We developed a three-dimensional simulation program that generates simple maps useful to assess rockFall Hazard, using GIS technology to manipulate existing thematic information available in digital format. The program requires as input a digital terrain model, the location of rock-Fall detachment areas, the dynamic friction coefficient used to simulate the loss of velocity during rolling, and the coefficients for normal and tangential energy restitution at the impact points. The program allows for the natural variability of the input data by using a random component approach. Raster outputs include the count of rock-Fall trajectories, the maximum velocity and the maximum height computed at each grid cell. Vector outputs consist of the planar (two dimensional) and the three-dimensional trajectories of the rock Falls. The program outputs proved to be consistent with the results of other rock-Fall simulation programs, to be reliable for modelling rock-Fall in three-dimensional geomorphological settings, and to help in the quantitative assessment of rock-Fall Hazard over large areas.