Challenges in the predictive simulation of cascading landslide processes

Mapping Intimacies ◽

10.5194/egusphere-egu21-14333 ◽

2021 ◽

Author(s):

Nina Marlovits ◽

Martin Mergili ◽

Thomas Glade

Keyword(s):

Risk Management ◽

Debris Flow ◽

Management Strategies ◽

Early Warning Systems ◽

Transition Phase ◽

Model Input ◽

Flow Processes ◽

Risk Management Strategies ◽

Hazard And Risk ◽

Ice Avalanche

History has shown that cascading landslides, such as the debris avalanches from Huascar&#225;n in 1962 and 1970, the Kolka-Karmadon rock-ice-avalanche in 2002, or the rock avalanche-debris flow event of Bondo in 2017, can be very destructive due to their high energies, velocities and volumes. They can lead to large numbers of fatalities, huge material damage, and disruption of critical infrastructure.Cascading landslides are a specific class of multi-hazard events in which one type of motion transforms into another or an initial, primary movement triggers a secondary process. High-mountain areas are particularly prone to this type of landslides due to their dynamic, rapidly changing environments and their high relief. For example, an initial rock fall can reach snow or ice masses and transform into a rock-snow- or rock-ice-avalanche, or into a debris flow. Physically-based numerical modelling is often used for the attempt to predict such events as a basis for the design of risk management strategies such as early warning systems. However, we identify at least two specific types of challenges making accurate and reliable predictions highly difficult:<ul><li>(a) The dynamic behaviour of such process chains, especially in the transition phase, is not yet fully understood. Existing models are either developed for (i) fall or (ii) flow processes. Whereas substantial progress has been made in previous years in the integrated simulation of flow-type movements, no software which fully and directly considers the transformation of fall to flow processes is known to the authors. Therefore, it is not yet possible to simulate fall-flow sequences of cascading landslide events with one single tool. Model chains have to be used instead, which have a limited capacity for appropriately representing the transition phase between the two types of processes.</li> <li>(b) Limited knowledge on the initial conditions and input parameters represents another severe limitation. Model input relies on available information on previous events and on certain characteristics of the (possible) release and impact area. Obviously, the quality of the data set is significantly influencing the model results. Whereas the scientific community is far away from exact predictions of landslide impact, an important objective should consist in better constraining the definition of possible scenarios to be considered for hazard and risk management.</li> </ul>For the reasons highlighted, it remains highly challenging to adequately predict the impact areas, energies, and travel times of cascading landslides in space and time. Nevertheless, stakeholders require such predictions for decisions on sustainable hazard and risk management strategies. Therefore, the aims of this study are (i) to evaluate possibilities to appropriately combine models for fall and flow processes and (ii) to examine data acquisition methods for the model input. Furthermore, (iii) appropriate strategies to present and to communicate simulation results need to be discussed.

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Reanalysis of Flash Floods and Debris Flows on two continents and their management strategies

10.5194/egusphere-egu21-373 ◽

2021 ◽

Author(s):

Juan Daniel Rios-Arboleda

Keyword(s):

Risk Management ◽

Developing Countries ◽

South America ◽

Debris Flow ◽

Debris Flows ◽

Large Scale ◽

Management Strategies ◽

Original Analysis ◽

Risk Management Strategies ◽

Latitudinal Patterns

This research expands the original analysis of Baker and Costa (1987) including data from Europe and South America with the objective to understand if there are emerging latitudinal patterns. In addition, the threshold proposed by Zimmermann et al. (1997) it is evaluated with the data from tropical zones finding that this is a good predictor.Mainly, recent Debris Flow occurred in South America are analyzed with the aim of identifying the best risk management strategies and their replicability for developing countries, particularly, the cases that have occurred in Colombia and Venezuela in the last 30 years are analyzed in order to compare management strategies and understand which are the most vulnerable areas to this phenomenon.It is concluded that large-scale and multinational projects such as SED ALP are required in South America to better characterize events that have left multiple fatalities (sometimes hundreds of people) and better understand how to manage the risk on densely populated areas.Finally, the use of amateur videos is proposed to characterize these events in nations with limited budgets for projects such as SED ALP, methodology that will be described extensively in later works.

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A criteria-set for the construction of a model cascade for fall-to-flow landslide chains

10.5194/egusphere-egu2020-7363 ◽

2020 ◽

Author(s):

Nina Marlovits ◽

Martin Mergili ◽

Alexander Preh ◽

Thomas Glade

Keyword(s):

Risk Management ◽

Process Model ◽

Management Strategies ◽

Simulation Models ◽

Spatial Transformation ◽

Negative Consequences ◽

Cascading Effects ◽

Flow Models ◽

Flow Processes ◽

Risk Management Strategies

Some of the most destructive landslide events in history have evolved through cascading effects where, for example, a rock fall in High Alpine areas transforms into a flow of rock, debris, ice, or snow. Amplification effects often result in high velocities and energies. As a result, such events can destroy private properties, infrastructure or can even lead to loss of life even in areas distant from the source.In order to reduce the negative consequences of cascading landslide processes, numerical modelling can enrich the efficiency of risk management strategies. Unfortunately, most landslide run-out simulation models are designed either for fall or flow processes. However, it is presumed that, at least in some cases, cascading effects cannot be properly represented by only one single process model. Due to the complexity of combining and comparing models for fall and flow processes, not many attempts to do so have been documented.In an attempt to fill this gap, the primary goal of this study is to define a criteria-set on how and when to couple the models, based on appropriate key parameters. Hence, we analyse computer models for fall and flow processes and evaluate whether their combination can provide an appropriate description of cascading landslides. A set of well-documented fall-flow events is back-calculated. Fall and flow are first simulated separately, with some overlap, each with a tool tailored for the corresponding process, based on detailed information on the case study. The input and output parameters for the overlapping areas are then analysed to investigate how and when process chains are linked. Thereby, one of the key challenges consists in the spatial transformation of the output of fall models to the input of flow models.The findings will be used to develop a simulation framework allowing for the automated combination of fall and flow models In order to efficiently perform simulations which can be used as input for the design of hazard and risk management measures.

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The December 2004-January 2005 floods in the Garden Route region of the Southern Cape, South Africa

Jàmbá Journal of Disaster Risk Studies ◽

10.4102/jamba.v2i2.18 ◽

2009 ◽

Vol 2 (2) ◽

Cited By ~ 1

Author(s):

Johan Tempelhoff ◽

Dewald Van Niekerk ◽

Elize Van Eeden ◽

Ina Gouws ◽

Karin Botha ◽

...

Keyword(s):

South Africa ◽

Risk Management ◽

Local Development ◽

Management Strategies ◽

Early Warning Systems ◽

Disaster Risk ◽

Disaster Risk Management ◽

Economic Activities ◽

Risk Management Strategies ◽

Infrastructure Maintenance

The December 2004-January 2005 floods in the Garden Route region of the Southern Cape in South Africa have had a significant impact on local development and economic activities, tourism products andlocal institutions. This article aims to capture the dynamism between a number of related fields within the context of transdisciplinary research. Qualitative research methods were used to target a representative sample of the affected population. This article considers the history of the flooding events of December 2004/January 2005 along the Garden Route, as well as the manner in which emergency/disaster management personnel responded to the crisis. The effect of the floods on the tourism sector along the Garden Route was researched in general and the effects of the floods on tourists, local residents, and particularly communities in disadvantaged areas were specifically determined. The research reflects on the disaster risk management strategies that were in place at the time of the floods to determine what local authorities could have done to cope with the potential conditions of crisis. The research found that although some tourism products were severely affected, the 2004/2005 floods did not have a significant impact on the number of tourists frequenting the area. In terms of disaster risk management, concerns remain regarding the lack of the following factors: capacity, adequate early warning systems, proper infrastructure maintenance, local institutions, and an in-depth understanding of the disaster risk profile of the area.

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Helping supervisees learn ethically based risk management strategies

PsycEXTRA Dataset ◽

10.1037/e500672008-001 ◽

2008 ◽

Author(s):

Samuel Knapp

Keyword(s):

Risk Management ◽

Management Strategies ◽

Risk Management Strategies

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The management of risk in a dryland environment

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2011.73.2835 ◽

2011 ◽

pp. 13-21

Author(s):

D.I. Gray ◽

J.I. Reid ◽

D.J. Horne

Keyword(s):

Risk Management ◽

Service Providers ◽

Management Strategies ◽

Subterranean Clover ◽

Farming Systems ◽

Market Risk ◽

Farm Size ◽

Forage Crops ◽

Risk Management Strategies ◽

Upside Risk

A group of 24 Hawke's Bay hill country farmers are working with service providers to improve the resilience of their farming systems. An important step in the process was to undertake an inventory of their risk management strategies. Farmers were interviewed about their farming systems and risk management strategies and the data was analysed using descriptive statistics. There was considerable variation in the strategies adopted by the farmers to cope with a dryland environment. Importantly, these strategies had to cope with three types of drought and also upside risk (better than expected conditions), and so flexibility was critical. Infra-structure was important in managing a dryland environment. Farmers chose between increased scale (increasing farm size) and geographic dispersion (owning a second property in another location) through to intensification (investing in subdivision, drainage, capital fertiliser, new pasture species). The study identified that there may be scope for further investment in infra-structural elements such as drainage, deeper rooting alternative pasture species and water harvesting, along with improved management of subterranean clover to improve flexibility. Many of the farmers used forage crops and idling capacity (reduced stocking rate) to improve flexibility; others argued that maintaining pasture quality and managing upside risk was a better strategy in a dryland environment. Supplementary feed was an important strategy for some farmers, but its use was limited by contour and machinery constraints. A surprisingly large proportion of farmers run breeding cows, a policy that is much less flexible than trading stock. However, several farmers had improved their flexibility by running a high proportion of trading cattle and buffer mobs of ewe hoggets and trade lambs. To manage market risk, the majority of farmers are selling a large proportion of their lambs prime. Similarly, cattle are either sold prime or store onto the grass market when prices are at a premium. However, market risk associated with the purchase of supplements and grazing was poorly managed.

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The Effects of Decision Aid Orientation on Risk Factor Identification and Audit Test Planning

Auditing A Journal of Practice & Theory ◽

10.2308/aud.2002.21.2.39 ◽

2002 ◽

Vol 21 (2) ◽

pp. 39-56 ◽

Cited By ~ 29

Author(s):

Jean C. Bedard ◽

Lynford E. Graham

Keyword(s):

Risk Factors ◽

Risk Management ◽

Decision Aid ◽

Decision Aids ◽

Management Strategies ◽

Risk Identification ◽

Matched Pair ◽

Audit Planning ◽

Audit Firms ◽

Risk Management Strategies

In auditing, risk management involves identifying client facts or issues that may affect engagement risk, and planning evidence-gathering strategies accordingly. The purpose of this paper is to examine whether auditors' identification of risk factors and planning of audit tests is affected by decision aid orientation, i.e., a “negative” focus wherein client risk and its consequences are emphasized, or a “positive” focus where such factors are not emphasized. Specifically, we expect that auditors will identify more risk factors using a negatively oriented risk identification decision aid, but only when engagement risk is relatively high. We address this issue in the context of auditors' knowledge of actual clients, manipulating decision aid orientation as negative or positive in a matched-pair design. Results show that auditors using the negative decision aid orientation identify more risk factors than do those using a positive orientation, for their higher-risk clients. We also find that decisions to apply substantive tests are more directly linked to specific risk factors identified than to direct risk assessments. Further, our results show that auditors with repeat engagement experience with the client identify more risk factors. The findings of this study imply that audit firms may improve their risk management strategies through simple changes in the design of decision aids used to support audit planning.

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Evaluation of Physical Risk during Necropsy and Morgue Activities as Risk Management Strategy

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18168266 ◽

2021 ◽

Vol 18 (16) ◽

pp. 8266

Author(s):

Zoe Del Fante ◽

Nicola Di Fazio ◽

Adriano Papale ◽

Paola Tomao ◽

Fabio Del Duca ◽

...

Keyword(s):

Risk Factors ◽

Risk Management ◽

Management Strategies ◽

Risk Management Strategy ◽

Work Related ◽

Activity Measurements ◽

Risk Management Strategies ◽

Physical Risk ◽

Critical Issues ◽

Load Handling

Physical risk assessments allow us to understand work-related critical issues, thus representing a useful tool in risk management strategies. In particular, our study focuses on the identification of already known and emerging physical risks related to necropsy and morgue activities, as well as crime scene investigations. The aim of our study is, therefore, to identify objective elements in order to quantify exposure to such risk factors among healthcare professionals and working personnel. For the research of potentially at-risk activities, data from the Morgue of Policlinico Umberto I Hospital in Rome were used. The scientific literature has been reviewed in order to assess the risks associated with morgue activity. Measurements were performed on previously scheduled days, in collaboration with the activities of different research units. The identified areas of risk were: microclimate; exposure to noise and vibrations; postural and biomechanical aspects of necropsy activities. The obtained results make it possible to detect interindividual variability in exposure to many of the aforementioned risk factors. In particular, the assessment of microclimate did not show significant results. On the contrary, exposure to vibrations and biomechanical aspects of load handling have shown potential risk profiles. For this reason, both profiles have been identified as possible action targets for risk management strategies.

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