Natural Hazards and Earth System Sciences

Syndicate content
Combined list of the recent articles of the journal Natural Hazards and Earth System Sciences and the recent discussion forum Natural Hazards and Earth System Sciences Discussions
Updated: 7 hours 46 min ago

Measuring compound flood potential from river discharge and storm surge extremes at the global scale and its implications for flood hazard

Fri, 07/19/2019 - 17:49
Measuring compound flood potential from river discharge and storm surge extremes at the global scale and its implications for flood hazard
Anaïs Couasnon, Dirk Eilander, Sanne Muis, Ted I. E. Veldkamp, Ivan D. Haigh, Thomas Wahl, Hessel Winsemius, and Philip J. Ward
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-205,2019
Manuscript under review for NHESS (discussion: open, 0 comments)

The interaction between physical drivers from oceanographic, hydrological, and meteorological processes in coastal areas can result in compound flooding. Compound flood events, like Cyclone Idai and Hurricane Harvey, have revealed the devastating consequences of the co-occurrence of coastal and river floods. A number of studies have recently investigated the likelihood of compound flooding at the continental scale based on simulated variables of flood drivers such as storm surge, precipitation, and river discharges. At the global scale, this has only been performed based on observations, thereby excluding a large extent of the global coastline. The purpose of this study is to fill this gap and identify potential hotspots of compound flooding from river discharge and storm surge extremes in river mouths globally. To do so, we use daily time-series of river discharge and storm surge from state-of-the-art global models driven with consistent meteorological forcing from reanalysis datasets. We measure the compound flood potential by analysing both variables with respect to their timing, joint statistical dependence, and joint return period. We find many hotspot regions of compound flooding that could not be identified in previous global studies based on observations alone, such as: Madagascar, Northern Morocco, Vietnam, and Taiwan. We report possible causal mechanisms for the observed spatial patterns based on existing literature. Finally, we provide preliminary insights on the implications of the bivariate dependence behaviour on the flood hazard characterisation using Madagascar as a case study. Our global and local analyses show that the dependence structure between flood drivers can be complex and can significantly impact the joint probability of discharge and storm surge extremes. These emphasise the need to refine global flood risk assessments and emergency planning to account for these potential interactions.

Reducing uncertainties in flood inundation outputs of a two-dimensional hydrodynamic model by constraining roughness

Thu, 07/18/2019 - 17:49
Reducing uncertainties in flood inundation outputs of a two-dimensional hydrodynamic model by constraining roughness
Punit Kumar Bhola, Jorge Leandro, and Markus Disse
Nat. Hazards Earth Syst. Sci., 19, 1445-1457, https://doi.org/10.5194/nhess-19-1445-2019, 2019
This study investigates the use of measured water levels to reduce uncertainty bounds of two-dimensional hydrodynamic model output. Uncertainty assessment is generally not reported in practice due to the lack of best practices and too wide uncertainty bounds. Hence, a novel method to reduce the bounds by constraining the model parameter, mainly roughness, is presented. The operational practitioners as well as researchers benefit from the study in the field of flood risk management.

Wildland fire potential outlooks for Portugal using meteorological indices of fire danger

Thu, 07/18/2019 - 17:49
Wildland fire potential outlooks for Portugal using meteorological indices of fire danger
Sílvia A. Nunes, Carlos C. DaCamara, Kamil F. Turkman, Teresa J. Calado, Ricardo M. Trigo, and Maria A. A. Turkman
Nat. Hazards Earth Syst. Sci., 19, 1459-1470, https://doi.org/10.5194/nhess-19-1459-2019, 2019
Portugal is recurrently affected by large wildfire events. We present a statistical model to estimate the probability that the summer burned area exceeds a given threshold. The model allows making outlooks of wildfire potential with up to 1 month in advance of the fire season. When applied to the 39-year period 1980-2018, only 1 severe (one weak) year is not anticipated as potentially severe (weak). The model will assist the fire community when planning prevention and combating fire events.

Remote sensing in an index-based insurance design for hedging economic impacts on rice cultivation

Thu, 07/18/2019 - 17:49
Remote sensing in an index-based insurance design for hedging economic impacts on rice cultivation
Omar Roberto Valverde-Arias, Paloma Esteve, Ana María Tarquis, and Alberto Garrido
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-183,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
We designed an index-based insurance (IBI) for drought and flood in rice crop, in Babahoyo canton (Ecuador). We assessed Babahoyo's soil, climatic and topographic variability, finding two homogeneous zones inside this area. We set differentiated insurance premiums according to the particular risk status of each zone. Results demonstrate that this IBI is an efficient risk transfer tool for policy holders. This insurance design could contribute to stabilize farmers' incomes and rice production.

Multi-coverage Optimal Location Model for Emergency Medical Services (EMS) facilities under various disaster scenarios: A case study of urban fluvial floods in the Minhang District of Shanghai, China

Thu, 07/18/2019 - 17:49
Multi-coverage Optimal Location Model for Emergency Medical Services (EMS) facilities under various disaster scenarios: A case study of urban fluvial floods in the Minhang District of Shanghai, China
Yuhan Yang and Jie Yin
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-214,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
Emergency medical services response is important for pre-hospital lifesaving, but disasters increase the difficulty of rescue so that increasing the pressure on EMS facilities. In order to avoid the failure of EMS facilities during disasters, we propose a multi-coverage optimal location model for EMS facilities based on the results of disaster risk assessment. Results showed that the optimized EMS locations reduced the delay in responses and significantly increased the number of rescued people.

Global detection of rainfall-triggered landslide clusters

Wed, 07/17/2019 - 17:49
Global detection of rainfall-triggered landslide clusters
Susanne A. Benz and Philipp Blum
Nat. Hazards Earth Syst. Sci., 19, 1433-1444, https://doi.org/10.5194/nhess-19-1433-2019, 2019
This study aims to identify clusters of landslide events within a global database that are triggered by the same rainfall event. Results show that 14 % of all recorded landslide events are actually part of a landslide cluster consisting of at least 10 events. However, in a more regional analysis this number ranges from 30 % for the west coast of North America to 3 % in the Himalayan region. These findings provide an improved understanding for managing landslide mitigations on a larger scale.

Contribution of personal weather stations to the observation of deep-convection features near the ground

Wed, 07/17/2019 - 17:49
Contribution of personal weather stations to the observation of deep-convection features near the ground
Marc Mandement and Olivier Caumont
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-229,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
The number of connected personal weather stations has dramatically increased in the last years. These weather stations produce massive amounts of data that need a thorough quality control to unleash their potential. A novel quality control algorithm now allows to take full advantage of these data and observe thunderstorms with fine-scale details that cannot be caught by standard networks. These results pave the way to tremendous advances in thunderstorm understanding and forecasting.

What's streamflow got to do with it? A probabilistic simulation of the competing oceanographic and fluvial processes driving extreme along-river water levels

Tue, 07/16/2019 - 17:49
What's streamflow got to do with it? A probabilistic simulation of the competing oceanographic and fluvial processes driving extreme along-river water levels
Katherine A. Serafin, Peter Ruggiero, Kai Parker, and David F. Hill
Nat. Hazards Earth Syst. Sci., 19, 1415-1431, https://doi.org/10.5194/nhess-19-1415-2019, 2019
In coastal environments, extreme water levels driving flooding are often generated by many individual processes like storm surge, streamflow, and tides. To estimate flood drivers along a coastal river, we merge statistical simulations of ocean and river forcing with a hydraulic model to produce water levels. We find both ocean and river forcing are necessary for producing extreme flood levels like the 100-yr event, highlighting the need for considering compound events in flood risk assessments.

Improving sub-seasonal forecast skill of meteorological drought: a weather pattern approach

Tue, 07/16/2019 - 17:49
Improving sub-seasonal forecast skill of meteorological drought: a weather pattern approach
Doug Richardson, Hayley J. Fowler, Chris G. Kilsby, Robert Neal, and Rutger Dankers
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-221,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
Models are not particularly skilful at forecasting rainfall more than 15 days in advance. However, they are often better at predicting atmospheric variables such as mean sea level pressure (MSLP). Comparing a range of models, we show that UK winter and autumn rainfall and drought prediction skill can be improved by utilising forecasts of MSLP-based weather patterns (WPs) and subsequently estimating rainfall using the historical WP-precipitation relationships.

Towards early warning of gravitational slope failure with co-detection of microseismic activity: the case of an active rock glacier

Mon, 07/15/2019 - 17:49
Towards early warning of gravitational slope failure with co-detection of microseismic activity: the case of an active rock glacier
Jérome Faillettaz, Martin Funk, Jan Beutel, and Andreas Vieli
Nat. Hazards Earth Syst. Sci., 19, 1399-1413, https://doi.org/10.5194/nhess-19-1399-2019, 2019
We developed a new strategy for real-time early warning of gravity-driven slope failures (such as landslides, rockfalls, glacier break-off, etc.). This method enables us to investigate natural slope stability based on continuous monitoring and interpretation of seismic waves generated by the potential instability. Thanks to a pilot experiment, we detected typical patterns of precursory events prior to slide events, demonstrating the potential of this method for real-word applications.

High-frequency glacial lake mapping using time series of Sentinel-1A/1B SAR imagery: An assessment for southeastern Tibetan Plateau

Mon, 07/15/2019 - 17:49
High-frequency glacial lake mapping using time series of Sentinel-1A/1B SAR imagery: An assessment for southeastern Tibetan Plateau
Meimei Zhang, Fang Chen, Bangsen Tian, Dong Liang, and Aqiang Yang
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-219,2019
Manuscript under review for NHESS (discussion: open, 0 comments)

Glacial lakes are important component of the cryosphere in the Tibetan Plateau. In response to climate warming, they threaten the downstream lives, ecological environment and public infrastructures through outburst floods in a short time. Although most of the efforts have been made to extract glacial lake outlines and detect their changes with remotely sensed images, the temporal frequency and spatial resolution of glacial lake datasets are generally not fine enough to reflect the detailed process of glacial lake dynamics, especially for potentially dangerous glacial lakes with high-frequency variability. By using a full time-series Sentinel-1A/1B imagery during a year, this study presents a new systematic method to extract the glacial lake outlines with fast variability in southeastern Tibetan Plateau at the time interval of six days. Our approach was based on the level-set segmentation, combined with a median pixel compositing of SAR backscattering coefficients stacks as regularization term, to robustly estimate the lake extent across the observed time range. The mapping results were validated against with manually digitized lake outlines derived from GF-2 PMS imagery, with the overall accuracy and Kappa coefficient of 96.54 % and 0.95, respectively. In comparison with results from classical supervised SVM and unsupervised ISODATA methods, the proposed method proves to be much more robust and effective to detect glacial lakes with irregular boundaries and that have similar backscattering with surroundings. This study also demonstrates the feasibility of time-series Sentinel-1A/1B SAR data in continuous monitoring of glacial lake outline dynamics.

From rapid visual survey to multi-hazard risk prioritisation and numerical fragility of school buildings

Thu, 07/11/2019 - 17:49
From rapid visual survey to multi-hazard risk prioritisation and numerical fragility of school buildings
Roberto Gentile, Carmine Galasso, Yunita Idris, Ibnu Rusydy, and Ella Meilianda
Nat. Hazards Earth Syst. Sci., 19, 1365-1386, https://doi.org/10.5194/nhess-19-1365-2019, 2019
This paper introduces the INSPIRE index, which quantifies the relative seismic risk of reinforced concrete buildings. A rapid visual survey form is proposed, which allows us to (1) calculate the INSPIRE index, (2) calculate a tsunami risk index, and (3) define archetype buildings to be analysed in more detail. The effectiveness of such tools is demonstrated with an application to 85 school buildings in Indonesia, also providing detailed numerical simulations for an archetype building.

Simultaneous state–parameter estimation of rainfall-induced landslide displacement using data assimilation

Thu, 07/11/2019 - 17:49
Simultaneous state–parameter estimation of rainfall-induced landslide displacement using data assimilation
Jing Wang, Guigen Nie, Shengjun Gao, and Changhu Xue
Nat. Hazards Earth Syst. Sci., 19, 1387-1398, https://doi.org/10.5194/nhess-19-1387-2019, 2019
It is necessary to do some prevention study of landslide hazard like the early warning and deformation prediction. This research proposes a new strategy to predict displacement of the landslide. Results confirm the accuracy and effectiveness of this method in displacement prediction, which can provide assistance in early risk assessment and landslide forecasting.

Hydro-meteorological reconstruction and geomorphological impact assessment of the October, 2018 catastrophic flash flood at Sant Llorenç, Mallorca (Spain)

Thu, 07/11/2019 - 17:49
Hydro-meteorological reconstruction and geomorphological impact assessment of the October, 2018 catastrophic flash flood at Sant Llorenç, Mallorca (Spain)
Jorge Lorenzo-Lacruz, Celso Garcia, Enrique Morán-Tejeda, Arnau Amengual, Víctor Homar, Aina Maimó-Far, Alejandro Hermoso, Climent Ramis, and Romualdo Romero
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-226,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
On October 9, 2018, an extreme convective storm (> 300 mm accumulated in 6 h.) generated a flash flood (307 m3/s) in the Ses Planes torrent that devastated the town of Sant Llorenç (Mallorca, Spain). Water reached a depth of 3 m in the most affected areas, and there was greatly increased flow velocity at bridges crossing the town. The floodwaters were very powerful and modified the channel morphology: more than 5000 metric tonnes of sediment were deposited in the 2 km reach upstream of the town.

Hydrometeorological Conditions Leading to the 2015 Salgar Flash Flood: Lessons for Vulnerable Regions in Tropical Complex Terrain

Wed, 07/10/2019 - 17:49
Hydrometeorological Conditions Leading to the 2015 Salgar Flash Flood: Lessons for Vulnerable Regions in Tropical Complex Terrain
Carlos D. Hoyos, Lina I. Ceballos, Jhayron S. Pérez, Julián Sepúlveda, Silvana M. López, Manuel D. Zuluaga, Nicolás Velásquez, Laura Herrera, Olver Hernández, Gisel Guzmán, and Mauricio Zapata
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-171,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
On the morning of May 18, 2015, a flash flood in La Liboriana river basin inundated the town of Salgar, killing more than one hundred people. The ultimate goal of science, regarding risk management, is to be able to reduce the number of people affected by severe storms. Our goal is to identify the meteorological conditions that led to the flood, assessing the characteristics of the rainfall events before the disaster, and identifying lessons for vulnerable regions settled in complex terrain.

Spatial Seismic Hazard Variation and Adaptive Sampling of Portfolio Location Uncertainty in Probabilistic Seismic Risk Analysis

Wed, 07/10/2019 - 17:49
Spatial Seismic Hazard Variation and Adaptive Sampling of Portfolio Location Uncertainty in Probabilistic Seismic Risk Analysis
Christoph Scheingraber and Martin Käser
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-110,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
Probabilistic Seismic Risk Analysis is widely used in the insurance industry to model losses to insured portfolios by earthquake events. Risk items are often only known to be located within an administrative geographical zone, but precise coordinates remain unknown to the modeler. We analyze spatial seismic hazard and loss rate variation inside administrative zones in western Indonesia. Building upon this, we present a novel framework for efficient treatment of portfolio location uncertainty.

Evaluation of a model for mapping intense pluvial runoff hazard using proxy data of runoff-related impacts. Application to the railway context

Wed, 07/10/2019 - 17:49
Evaluation of a model for mapping intense pluvial runoff hazard using proxy data of runoff-related impacts. Application to the railway context
Isabelle Braud, Lilly-Rose Lagadec, Loïc Moulin, Blandine Chazelle, and Pascal Breil
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-208,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
A method for the evaluation of a model that maps the susceptibility of a territory to surface runoff is presented. It is based on proxy data of localized impacts related to runoff. It accounts for the hazard level, the vulnerability of the study area and possible mitigation actions taken to reduce the risk. The evaluation is made on a 80 km railway line in Normandy (North of France), where a comprehensive database of runoff-related impacts on the railway has been gathered over the 20th century.

Integrated sea storm management strategy: the 29 October 2018 event in the Adriatic Sea

Tue, 07/09/2019 - 17:49
Integrated sea storm management strategy: the 29 October 2018 event in the Adriatic Sea
Christian Ferrarin, Andrea Valentini, Martin Vodopivec, Dijana Klaric, Giovanni Massaro, Marco Bajo, Francesca De Pascalis, Amedeo Fadini, Michol Ghezzo, Stefano Menegon, Lidia Bressan, Silvia Unguendoli, Anja Fettich, Jure Jerman, Matjaž Licer, Lidija Fustar, Alvise Papa, and Enrico Carraro
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-212,2019
Manuscript under review for NHESS (discussion: open, 0 comments)

Addressing coastal risks related to sea storms requires an integrative approach which combines monitoring stations, forecasting models, early warning systems and coastal management and planning. Such great effort is sometimes possible only through transnational cooperation, which becomes thus vital to face effectively and promptly these marine events which are responsible for several damages impacting on the environment and citizens' life. Here we present a shared and interoperable system to allow a better exchange and elaboration of information related to sea storms among countries. The proposed Integrated Web System (IWS) is a combination of a common data system for sharing ocean observations and forecasts, a multi-model ensemble system, a geoportal and interactive geo-visualization tools to make results available to the general public. Multi-model ensemble mean and spread for sea level height and wave characteristics are used to describe three different sea condition scenarios. IWS is designed to provide sea state information required for issuing coastal risk alerts over the analysed region, as well as for being easily integrated into existing local early warning systems. This study describes the application of the developed system to the exceptional storm event of 29th of October 2018, that caused severe flooding and damages to coastal infrastructures in the Adriatic Sea. The forecasted ensemble products were successfully compared with in situ observations. The hazards estimated by integrating IWS results into existing early warning systems were confirmed by documented storm impacts along the coast of Slovenia, Emilia-Romagna and the City of Venice. For the investigated event, the most severe simulated scenario resulted to provide a realistic and conservative estimation of the peak storm conditions to be used in coastal risk management.

Analysis of Employment Change in Response to Hurricane Landfalls

Tue, 07/09/2019 - 17:49
Analysis of Employment Change in Response to Hurricane Landfalls
Yuepeng Cui, Daan Liang, and Bradley Ewing
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-201,2019
Manuscript under review for NHESS (discussion: open, 1 comment)
The methodology presented in this paper is considered as an important entry point to addressing the complex problems related to disaster resilience. Regardless of storms, hurricane impact on local employment is found to be either temporary or permanent in nature.Relating the concept of resilience to observable socioeconomic activities helps us gaining a deeper understanding of the drivers and the processes of of post-storm recovery. Studies play a major role in bridging the knowledge gaps.

Case Study: Risk Analysis by Overtopping During an Upstream Landslide in Peñitas Dam, Mexico

Tue, 07/09/2019 - 17:49
Case Study: Risk Analysis by Overtopping During an Upstream Landslide in Peñitas Dam, Mexico
Humberto J. F. Marengo and Alvaro A. Aldama
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-191,2019
Manuscript under review for NHESS (discussion: open, 0 comments)
In this paper is made a risk analysis by overtopping of existing Peñitas dam that could be caused by a flood produced by the failure of an upstream natural dam product of a landslide: is showed a real case and its solution; innovative mathematical approach analysis is presented. Risk model analysis developed is applicable to similar cases could happen in any site of the world. Uncertainty analysis of variables that have their own hypotheses, limitations, advantages and disadvantages is made.

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer