Natural Hazards and Earth System Sciences

Nearshore tsunami amplitudes across the Maldives archipelago due to worst-case seismic scenarios in the Indian Ocean
Shuaib Rasheed, Simon C. Warder, Yves Plancherel, and Matthew D. Piggott
Nat. Hazards Earth Syst. Sci., 24, 737–755, https://doi.org/10.5194/nhess-24-737-2024, 2024
Here we use a high-resolution bathymetry dataset of the Maldives archipelago, as well as corresponding high numerical model resolution, to carry out a scenario-based tsunami hazard assessment for the entire Maldives archipelago to investigate the potential impact of plausible far-field tsunamis across the Indian Ocean at the island scale. The results indicate that several factors contribute to mitigating and amplifying tsunami waves at the island scale.

Seasonal forecasting of local-scale soil moisture droughts with Global BROOK90: a case study of the European drought of 2018
Ivan Vorobevskii, Thi Thanh Luong, and Rico Kronenberg
Nat. Hazards Earth Syst. Sci., 24, 681–697, https://doi.org/10.5194/nhess-24-681-2024, 2024
This study presents a new version of a framework which allows us to model water balance components at any site on a local scale. Compared with the first version, the second incorporates new datasets used to set up and force the model. In particular, we highlight the ability of the framework to provide seasonal forecasts. This gives potential stakeholders (farmers, foresters, policymakers, etc.) the possibility to forecast, for example, soil moisture drought and thus apply the necessary measures.

Tsunami hazard perception and knowledge of alert: early findings in five municipalities along the French Mediterranean coastlines
Johnny Douvinet, Noé Carles, Pierre Foulquier, and Matthieu Peroche
Nat. Hazards Earth Syst. Sci., 24, 715–735, https://doi.org/10.5194/nhess-24-715-2024, 2024
This study provided an opportunity to assess both the perception of the tsunami hazard and the knowledge of alerts in five municipalities located along the French Mediterranean coastlines. The age and location of the respondents explain several differences between the five municipalities surveyed – more so than gender or residence status. This study may help local authorities to develop future tsunami awareness actions and to identify more appropriate strategies to be applied in the short term.

Mapping current and future flood exposure using a 5 m flood model and climate change projections
Connor Darlington, Jonathan Raikes, Daniel Henstra, Jason Thistlethwaite, and Emma K. Raven
Nat. Hazards Earth Syst. Sci., 24, 699–714, https://doi.org/10.5194/nhess-24-699-2024, 2024
The impacts of climate change on local floods require precise maps that clearly demarcate changes to flood exposure; however, most maps lack important considerations that reduce their utility in policy and decision-making. This article presents a new approach to identifying current and projected flood exposure using a 5 m model. The results highlight advancements in the mapping of flood exposure with implications for flood risk management.

A New Method for Calculating Highway Blocking due to High Impact Weather Conditions
Duanyang Liu, Tian Jing, Mingyue Yan, Ismail Gultepe, Yunxuan Bao, Hongbin Wang, and Fan Zu
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2023-230,2024
Preprint under review for NHESS (discussion: open, 1 comment)
The highway-blocking events are characterized by diurnal variation. A classification method of severity levels of highway blocking is developed into five levels. The severity levels of highway blocking due to high-impact weather are evaluated. A method for calculating the degree of highway load in China is proposed. A quantitative assessment of the losses of highway blocking due to dense fog is conducted. The highway losses caused by dense fog are concentrated in North, East and Southwest China.

Dependence Models for Multi-Hazard-Events
Georg C. Pflug, Viktoria Kittler, and Stefan Hochrainer-Stigler
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2023-194,2024
Preprint under review for NHESS (discussion: open, 1 comment)
Multi-hazard events can be devastating and there are indications that in such situations the exposed risk-bearers are affected more severely compared to single-hazard events. We present some statistical modeling approaches to determine possible interrelationships of hazards and tested them for the specific case of the countries within the Danube Region. We especially focused on the question whether certain hazards are more likely to occur due to preceding hazardous events.

Brief communication: On the environmental impacts of the 2023 floods in Emilia-Romagna (Italy)
Chiara Arrighi and Alessio Domeneghetti
Nat. Hazards Earth Syst. Sci., 24, 673–679, https://doi.org/10.5194/nhess-24-673-2024, 2024
In this communication, we reflect on environmental flood impacts by analysing the reported environmental consequences of the 2023 Emilia-Romagna floods. The most frequently reported damage involves water resources and water-related ecosystems. Indirect effects in time and space, intrinsic recovery capacity, cascade impacts on socio-economic systems, and the lack of established monitoring activities appear to be the most challenging aspects for future research.

Insurance loss model vs meteorological loss index – How comparable are their loss estimates for European windstorms?
Julia Moemken, Inovasita Alifdini, Alexandre M. Ramos, Alexandros Georgiadis, Aidan Brocklehurst, Lukas Braun, and Joaquim G. Pinto
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2024-16,2024
Preprint under review for NHESS (discussion: open, 0 comments)
European windstorms regularly cause damage to natural and human-made environments, leading to high socio-economic losses. For the first time, we compare estimates of these losses using a meteorological Loss Index (LI) and the insurance loss (catastrophe) model of Aon Impact Forecasting. We find that LI underestimates high impact windstorms compared to the insurance model. Nonetheless, due to its simplicity, LI is an effective index, suitable for estimating impacts and ranking storm events.

Seismogenic depth and seismic coupling estimation in the transition zone between Alps, Dinarides and Pannonian Basin for the new Slovenian seismic hazard model
Polona Zupančič, Barbara Šket Motnikar, Michele M. C. Carafa, Petra Jamšek Rupnik, Mladen Živčić, Vanja Kastelic, Gregor Rajh, Martina Čarman, Jure Atanackov, and Andrej Gosar
Nat. Hazards Earth Syst. Sci., 24, 651–672, https://doi.org/10.5194/nhess-24-651-2024, 2024
We considered two parameters that affect seismic hazard assessment in Slovenia. The first parameter we determined is the thickness of the lithosphere's section where earthquakes are generated. The second parameter is the activity of each fault, which is expressed by its average displacement per year (slip rate). Since the slip rate can be either seismic or aseismic, we estimated both components. This analysis was based on geological and seismological data and was validated through comparisons.

Optimization strategy for flexible barrier structures: investigation and back analysis of a rockfall disaster case in southwestern China
Li-Ru Luo, Zhi-Xiang Yu, Li-Jun Zhang, Qi Wang, Lin-Xu Liao, and Li Peng
Nat. Hazards Earth Syst. Sci., 24, 631–649, https://doi.org/10.5194/nhess-24-631-2024, 2024
We performed field investigations on a rockfall near Jiguanshan National Forest Park, Chengdu. Vital information was obtained from an unmanned aerial vehicle survey. A finite element model was created to reproduce the damage evolution. We found that the impact kinetic energy was below the design protection energy. Improper member connections prevent the barrier from producing significant deformation to absorb energy. Damage is avoided by improving the ability of the nets and ropes to slide.

Comparison of conditioning factors classification criteria in large scale statistically based landslide susceptibility models
Marko Sinčić, Sanja Bernat Gazibara, Mauro Rossi, and Snježana Mihalić Arbanas
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2024-29,2024
Preprint under review for NHESS (discussion: open, 0 comments)
The paper focuses on classifying continuous landslide conditioning factors for susceptibility modelling, which resulted in 54 landslide susceptibility models that tested 11 classification criteria in combination with five statistical methods. The novelty of the research is that using stretched landslide conditioning factor values results in models with higher accuracy and that certain statistical methods are more sensitive to the landslide conditioning factor classification criteria than others.

How to mitigate flood events similar to the 1979 catastrophic floods in the lower Tagus
Diego Fernández-Nóvoa, Alexandre M. Ramos, José González-Cao, Orlando García-Feal, Cristina Catita, Moncho Gómez-Gesteira, and Ricardo M. Trigo
Nat. Hazards Earth Syst. Sci., 24, 609–630, https://doi.org/10.5194/nhess-24-609-2024, 2024
The present study focuses on an in-depth analysis of floods in the lower section of the Tagus River from a hydrodynamic perspective by means of the Iber+ numerical model and on the development of dam operating strategies to mitigate flood episodes using the exceptional floods of February 1979 as a benchmark. The results corroborate the model's capability to evaluate floods in the study area and confirm the effectiveness of the proposed strategies to reduce flood impact in the lower Tagus valley.

Probabilistic Flood Inundation Mapping through Copula Bayesian Multi-Modelling of Precipitation Products
Francisco Javier Gomez, Keighobad Jafarzadegan, Hamed Moftakhari, and Hamid Moradkhani
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2024-26,2024
Preprint under review for NHESS (discussion: open, 1 comment)
This study utilizes the Global Copula Bayesian Model Averaging technique for accurate and reliable flood modeling, especially in coastal regions. By integrating multiple precipitation datasets within this framework, we can effectively address sources of error in each dataset, leading to the generation of probabilistic flood maps. The creation of these probabilistic maps is essential for disaster preparedness and mitigation in densely populated areas susceptible to extreme weather events.

An Efficient Method to Simulate Wildfire Propagation Using Irregular Grids
Conor Hackett, Rafael de Andrade Moral, Gourav Mishra, Tim McCarthy, and Charles Markham
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2024-27,2024
Preprint under review for NHESS (discussion: open, 3 comments)
This paper reviews existing wildfire propagation models and a comparison of different grid types including random grids to simulate wildfires. This paper finds that irregular grids simulate wildfires more efficiently than continuous models while still retaining a reasonable level of similarity. It also shows that irregular grids tend to retain greater similarity to continuous models than regular grids at the cost of slightly longer computational times.

Towards a dynamic earthquake risk framework for Switzerland
Maren Böse, Laurentiu Danciu, Athanasios Papadopoulos, John Clinton, Carlo Cauzzi, Irina Dallo, Leila Mizrahi, Tobias Diehl, Paolo Bergamo, Yves Reuland, Andreas Fichtner, Philippe Roth, Florian Haslinger, Frédérick Massin, Nadja Valenzuela, Nikola Blagojević, Lukas Bodenmann, Eleni Chatzi, Donat Fäh, Franziska Glueer, Marta Han, Lukas Heiniger, Paulina Janusz, Dario Jozinović, Philipp Kästli, Federica Lanza, Timothy Lee, Panagiotis Martakis, Michèle Marti, Men-Andrin Meier, Banu Mena Cabrera, Maria Mesimeri, Anne Obermann, Pilar Sanchez-Pastor, Luca Scarabello, Nicolas Schmid, Anastasiia Shynkarenko, Bozidar Stojadinović, Domenico Giardini, and Stefan Wiemer
Nat. Hazards Earth Syst. Sci., 24, 583–607, https://doi.org/10.5194/nhess-24-583-2024, 2024
Seismic hazard and risk are time dependent as seismicity is clustered and exposure can change rapidly. We are developing an interdisciplinary dynamic earthquake risk framework for advancing earthquake risk mitigation in Switzerland. This includes various earthquake risk products and services, such as operational earthquake forecasting and early warning. Standardisation and harmonisation into seamless solutions that access the same databases, workflows, and software are a crucial component.

Assessing LISFLOOD-FP with the next-generation digital elevation model FABDEM using household survey and remote sensing data in the Central Highlands of Vietnam
Laurence Hawker, Jeffrey Neal, James Savage, Thomas Kirkpatrick, Rachel Lord, Yanos Zylberberg, Andre Groeger, Truong Dang Thuy, Sean Fox, Felix Agyemang, and Pham Khanh Nam
Nat. Hazards Earth Syst. Sci., 24, 539–566, https://doi.org/10.5194/nhess-24-539-2024, 2024
We present a global flood model built using a new terrain data set and evaluated in the Central Highlands of Vietnam.

Evaluating pySTEPS optical flow algorithms for convection nowcasting over the Maritime Continent using satellite data
Joseph Smith, Cathryn Birch, John Marsham, Simon Peatman, Massimo Bollasina, and George Pankiewicz
Nat. Hazards Earth Syst. Sci., 24, 567–582, https://doi.org/10.5194/nhess-24-567-2024, 2024
Nowcasting uses observations to make predictions of the atmosphere on short timescales and is particularly applicable to the Maritime Continent, where storms rapidly develop and cause natural disasters. This paper evaluates probabilistic and deterministic satellite nowcasting algorithms over the Maritime Continent. We show that the probabilistic approach is most skilful at small scales (~ 60 km), whereas the deterministic approach is most skilful at larger scales (~ 200 km).

Converging Human Intelligence with AI Systems to Advance Flood Evacuation Decision Making
Rishav Karanjit, Vidya Samadi, Amanda Hughes, Pamela Murray-Tuite, and Keri Stephens
Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2024-25,2024
Preprint under review for NHESS (discussion: open, 0 comments)
This research paper focused on creating a new paradigm for flood evacuation decisions – so-called human-AI Convergence (HAC) system. A Natural Language Processing (NLP) method was used to mine and filter human data from X posts that were deemed relevant to flooding. The human data along with a river hydraulic model and AI algorithms were integrated into an evacuation re-routing algorithm to forecast flood depth and define evacuation decisions.

Investigation of historical severe storms and storm tides in the German Bight with century reanalysis data
Elke Magda Inge Meyer and Lidia Gaslikova
Nat. Hazards Earth Syst. Sci., 24, 481–499, https://doi.org/10.5194/nhess-24-481-2024, 2024
Storm tides for eight extreme historical storms in the German Bight are modelled using sets of slightly varying atmospheric conditions from the century reanalyses. Comparisons with the water level observations from the gauges Norderney, Cuxhaven and Husum show that single members of the reanalyses are suitable for the reconstruction of extreme storms. Storms with more northerly tracks show less variability within a set and have more potential for accurate reconstruction of extreme water levels.

CRHyME (Climatic Rainfall Hydrogeological Modelling Experiment): a new model for geo-hydrological hazard assessment at the basin scale
Andrea Abbate, Leonardo Mancusi, Francesco Apadula, Antonella Frigerio, Monica Papini, and Laura Longoni
Nat. Hazards Earth Syst. Sci., 24, 501–537, https://doi.org/10.5194/nhess-24-501-2024, 2024
CRHyME (Climatic Rainfall Hydrogeological Modelling Experiment) is a new physically based and spatially distributed rainfall-runoff model. The main novelties consist of reproducing rainfall-induced geo-hydrological hazards such as shallow landslide, debris flow and watershed erosion through a multi-hazard approach. CRHyME was written in Python, works at a high spatial and temporal resolution, and is a tool suitable for quantifying extreme rainfall consequences at the basin scale.