Articles | Volume 21, issue 6
Nat. Hazards Earth Syst. Sci., 21, 1867–1885, 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
17 Jun 2021
Research article | 17 Jun 2021
Towards a compound-event-oriented climate model evaluation: a decomposition of the underlying biases in multivariate fire and heat stress hazards
Roberto Villalobos-Herrera et al.
No articles found.
Yann Quilcaille, Fulden Batibeniz, Andreia F. S. Ribeiro, Ryan S. Padrón, and Sonia I. Seneviratne
Earth Syst. Sci. Data Discuss.,
Preprint under review for ESSDShort summary
We present a new database of four annual fire weather indicators over 1850–2100 and over all land area. Our first analysis shows that in a 3 °C warmer world with respect to preindustrial times, the mean fire weather would on average double in duration and intensity. The produced dataset is a freely available resource for fire danger studies and beyond, highlighting that the best course of action would require limiting global warming as low as possible.
Matthias Aichinger-Rosenberger, Elmar Brockmann, Laura Crocetti, Benedikt Soja, and Gregor Moeller
Atmos. Meas. Tech., 15, 5821–5839,Short summary
This study develops an innovative approach for the detection and prediction of foehn winds. The approach uses products generated from GNSS (Global Navigation Satellite Systems) in combination with machine learning-based classification algorithms to detect and predict foehn winds at Altdorf, Switzerland. Results are encouraging and comparable to similar studies using meteorological data, which might qualify the method as an additional tool for short-term foehn forecasting in the future.
Natacha Le Grix, Jakob Zscheischler, Keith Rodgers, Ryohei Yamaguchi, and Thomas Lukas Frölicher
Compound events threaten marine ecosystems. Here, we investigate the potentially harmful combination of marine heatwaves with low phytoplankton productivity. Using satellite-based observations, we show that these compound events are frequent in the low latitudes. We then investigate the drivers of these compound events using Earth System models. The models share similar drivers in the low latitudes, but disagree in the high latitudes due to divergent factors limiting phytoplankton production.
Alexandre Tuel, Bettina Schaefli, Jakob Zscheischler, and Olivia Martius
Hydrol. Earth Syst. Sci., 26, 2649–2669,Short summary
River discharge is strongly influenced by the temporal structure of precipitation. Here, we show how extreme precipitation events that occur a few days or weeks after a previous event have a larger effect on river discharge than events occurring in isolation. Windows of 2 weeks or less between events have the most impact. Similarly, periods of persistent high discharge tend to be associated with the occurrence of several extreme precipitation events in close succession.
Greta Cazzaniga, Carlo De Michele, Michele D'Amico, Cristina Deidda, Antonio Ghezzi, and Roberto Nebuloni
Hydrol. Earth Syst. Sci., 26, 2093–2111,Short summary
Rainfall estimates are usually obtained from rain gauges, weather radars, or satellites. An alternative is the measurement of the signal loss induced by rainfall on commercial microwave links (CMLs). In this work, we assess the hydrologic response of Lambro Basin when CML-retrieved rainfall is used as model input. CML estimates agree with rain gauge data. CML-driven discharge simulations show performance comparable to that from rain gauges if a CML-based calibration of the model is undertaken.
Shijie Jiang, Emanuele Bevacqua, and Jakob Zscheischler
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
We use explainable machine learning to identify the contribution of recent precipitation, antecedent precipitation, and snowmelt to individual flood events in Europe. More than half of catchments are found dominated by mixed flooding mechanisms. Over the past 70 years, changes in the dominant flooding mechanisms are observed within a number of catchments. Generally, the number of floods induced by snowmelt has declined significantly, while floods triggered by recent precipitation have increased.
Elisabeth Tschumi, Sebastian Lienert, Karin van der Wiel, Fortunat Joos, and Jakob Zscheischler
Biogeosciences, 19, 1979–1993,Short summary
Droughts and heatwaves are expected to occur more often in the future, but their effects on land vegetation and the carbon cycle are poorly understood. We use six climate scenarios with differing extreme occurrences and a vegetation model to analyse these effects. Tree coverage and associated plant productivity increase under a climate with no extremes. Frequent co-occurring droughts and heatwaves decrease plant productivity more than the combined effects of single droughts or heatwaves.
Fabiola Banfi and Carlo De Michele
The Cryosphere, 16, 1031–1056,Short summary
Climate changes require a dynamic description of glaciers in hydrological models. In this study we focus on the local modelling of snow and firn. We tested our model at the site of Colle Gnifetti, 4400–4550 m a.s.l. The model shows that wind erodes all the precipitation of the cold months, while snow is in part conserved between April and September since higher temperatures protect snow from erosion. We also compared modelled and observed firn density, obtaining a satisfying agreement.
Colin Manning, Emanuele Bevacqua, Martin Widmann, Douglas Maraun, and Anne F. Van Loon
Weather Clim. Dynam. Discuss.,
Revised manuscript under review for WCDShort summary
This article shows that climate models largely differ in their representation of persistent dry spells that co-occur with extremely high temperatures. Some models simulate dry spells that are too short and too cool compared to observations, while others simulate dry spells that are too long and too hot. This information is important when interpreting the likelihood of such events in a warmer climate so that we can assess the plausibility of their future projections.
Jun Li, Zhaoli Wang, Xushu Wu, Jakob Zscheischler, Shenglian Guo, and Xiaohong Chen
Hydrol. Earth Syst. Sci., 25, 1587–1601,Short summary
We introduce a daily-scale index, termed the standardized compound drought and heat index (SCDHI), to measure the key features of compound dry-hot conditions. SCDHI can not only monitor the long-term compound dry-hot events, but can also capture such events at sub-monthly scale and reflect the related vegetation activity impacts. The index can provide a new tool to quantify sub-monthly characteristics of compound dry-hot events, which are vital for releasing early and timely warning.
Natacha Le Grix, Jakob Zscheischler, Charlotte Laufkötter, Cecile S. Rousseaux, and Thomas L. Frölicher
Biogeosciences, 18, 2119–2137,Short summary
Marine ecosystems could suffer severe damage from the co-occurrence of a marine heat wave with extremely low chlorophyll concentration. Here, we provide a first assessment of compound marine heat wave and low-chlorophyll events in the global ocean from 1998 to 2018. We reveal hotspots of these compound events in the equatorial Pacific and in the Arabian Sea and show that they mostly occur in summer at high latitudes and their frequency is modulated by large-scale modes of climate variability.
Johannes Vogel, Pauline Rivoire, Cristina Deidda, Leila Rahimi, Christoph A. Sauter, Elisabeth Tschumi, Karin van der Wiel, Tianyi Zhang, and Jakob Zscheischler
Earth Syst. Dynam., 12, 151–172,Short summary
We present a statistical approach for automatically identifying multiple drivers of extreme impacts based on LASSO regression. We apply the approach to simulated crop failure in the Northern Hemisphere and identify which meteorological variables including climate extreme indices and which seasons are relevant to predict crop failure. The presented approach can help unravel compounding drivers in high-impact events and could be applied to other impacts such as wildfires or flooding.
Marco Bongio, Ali Nadir Arslan, Cemal Melih Tanis, and Carlo De Michele
The Cryosphere, 15, 369–387,Short summary
The capability of time-lapse photography to retrieve snow depth time series was tested. We demonstrated that this method can be efficiently used in three different case studies: two in the Italian Alps and one in a forested region of Finland, with an accuracy comparable to the most common methods such as ultrasonic sensors or manual measurements. We hope that this simple method based only on a camera and a graduated stake can enable snow depth measurements in dangerous and inaccessible sites.
Fabiola Banfi and Carlo De Michele
The Cryosphere Discuss.,
Manuscript not accepted for further reviewShort summary
Climate changes require a dynamic description of glaciers in hydrological models. In this study we focus on the local modeling of snow and firn. We tested our model at the site of Colle Gnifetti, 4400–4550 m a.s.l. The model shows that wind erodes all the precipitation of the cold months, while snow is in part conserved between May and September, since higher temperatures protect snow from erosion. We also compared modeled and observed firn density obtaining a satisfying agreement.
Jakob Zscheischler, Philippe Naveau, Olivia Martius, Sebastian Engelke, and Christoph C. Raible
Earth Syst. Dynam., 12, 1–16,Short summary
Compound extremes such as heavy precipitation and extreme winds can lead to large damage. To date it is unclear how well climate models represent such compound extremes. Here we present a new measure to assess differences in the dependence structure of bivariate extremes. This measure is applied to assess differences in the dependence of compound precipitation and wind extremes between three model simulations and one reanalysis dataset in a domain in central Europe.
Andreia Filipa Silva Ribeiro, Ana Russo, Célia Marina Gouveia, Patrícia Páscoa, and Jakob Zscheischler
Biogeosciences, 17, 4815–4830,Short summary
This study investigates the impacts of compound dry and hot extremes on crop yields, namely wheat and barley, over two regions in Spain dominated by rainfed agriculture. We provide estimates of the conditional probability of crop loss under compound dry and hot conditions, which could be an important tool for responsible authorities to mitigate the impacts magnified by the interactions between the different hazards.
Emanuele Bevacqua, Michalis I. Vousdoukas, Theodore G. Shepherd, and Mathieu Vrac
Nat. Hazards Earth Syst. Sci., 20, 1765–1782,Short summary
Coastal compound flooding (CF), caused by interacting storm surges and high water runoff, is typically studied based on concurring storm surge extremes with either precipitation or river discharge extremes. Globally, these two approaches show similar CF spatial patterns, especially where the CF potential is the highest. Deviations between the two approaches increase with the catchment size. The precipitation-based analysis allows for considering local-rainfall-driven CF and CF in small rivers.
Andreia F. S. Ribeiro, Ana Russo, Célia M. Gouveia, Patrícia Páscoa, and Carlos A. L. Pires
Nat. Hazards Earth Syst. Sci., 19, 2795–2809,Short summary
This work investigates the dependence between drought hazard and yield anomalies of rainfed cropping systems in the Iberian Peninsula using the copula theory. The applied methodology allows us to estimate the likelihood of wheat and barley loss under drought conditions, and a dependence among extreme values is suggested. From the decision-making point of view this study aims to contribute to the mitigation of drought-related crop failure.
Inne Vanderkelen, Jakob Zschleischler, Lukas Gudmundsson, Klaus Keuler, Francois Rineau, Natalie Beenaerts, Jaco Vangronsveld, and Wim Thiery
Manuscript not accepted for further review
Jakob Zscheischler, Erich M. Fischer, and Stefan Lange
Earth Syst. Dynam., 10, 31–43,Short summary
Many climate models have biases in different variables throughout the world. Adjusting these biases is necessary for estimating climate impacts. Here we demonstrate that widely used univariate bias adjustment methods do not work well for multivariate impacts. We illustrate this problem using fire risk and heat stress as impact indicators. Using an approach that adjusts not only biases in the individual climate variables but also biases in the correlation between them can resolve these problems.
Martha M. Vogel, Jakob Zscheischler, and Sonia I. Seneviratne
Earth Syst. Dynam., 9, 1107–1125,Short summary
Climate change projections of temperature extremes are particularly uncertain in central Europe. We demonstrate that varying soil moisture–atmosphere feedbacks in current climate models leads to an enhancement of model differences; thus, they can explain the large uncertainties in extreme temperature projections. Using an observation-based constraint, we show that the strong drying and large increase in temperatures exhibited by models on the hottest day in central Europe are highly unlikely.
Donghai Wu, Philippe Ciais, Nicolas Viovy, Alan K. Knapp, Kevin Wilcox, Michael Bahn, Melinda D. Smith, Sara Vicca, Simone Fatichi, Jakob Zscheischler, Yue He, Xiangyi Li, Akihiko Ito, Almut Arneth, Anna Harper, Anna Ukkola, Athanasios Paschalis, Benjamin Poulter, Changhui Peng, Daniel Ricciuto, David Reinthaler, Guangsheng Chen, Hanqin Tian, Hélène Genet, Jiafu Mao, Johannes Ingrisch, Julia E. S. M. Nabel, Julia Pongratz, Lena R. Boysen, Markus Kautz, Michael Schmitt, Patrick Meir, Qiuan Zhu, Roland Hasibeder, Sebastian Sippel, Shree R. S. Dangal, Stephen Sitch, Xiaoying Shi, Yingping Wang, Yiqi Luo, Yongwen Liu, and Shilong Piao
Biogeosciences, 15, 3421–3437,Short summary
Our results indicate that most ecosystem models do not capture the observed asymmetric responses under normal precipitation conditions, suggesting an overestimate of the drought effects and/or underestimate of the watering impacts on primary productivity, which may be the result of inadequate representation of key eco-hydrological processes. Collaboration between modelers and site investigators needs to be strengthened to improve the specific processes in ecosystem models in following studies.
Katia Cugerone, Carlo De Michele, Antonio Ghezzi, Vorne Gianelle, and Stefania Gilardoni
Atmos. Chem. Phys., 18, 4831–4842,Short summary
The aerosol particle number size distributions (PNSDs) measured in one urban background site (Milan) and in one rural mountainous site (Oga San Colombano) have been studied and compared. Detailed statistical analyses have shown that a common empirical PNSD pattern exists, except for the urban winter data. In order to explain this phenomenon, we analysed the aerosol dynamics by considering the influence of primary aerosol components and the interaction with precipitation and high wind speed.
Jannis von Buttlar, Jakob Zscheischler, Anja Rammig, Sebastian Sippel, Markus Reichstein, Alexander Knohl, Martin Jung, Olaf Menzer, M. Altaf Arain, Nina Buchmann, Alessandro Cescatti, Damiano Gianelle, Gerard Kiely, Beverly E. Law, Vincenzo Magliulo, Hank Margolis, Harry McCaughey, Lutz Merbold, Mirco Migliavacca, Leonardo Montagnani, Walter Oechel, Marian Pavelka, Matthias Peichl, Serge Rambal, Antonio Raschi, Russell L. Scott, Francesco P. Vaccari, Eva van Gorsel, Andrej Varlagin, Georg Wohlfahrt, and Miguel D. Mahecha
Biogeosciences, 15, 1293–1318,Short summary
Our work systematically quantifies extreme heat and drought event impacts on gross primary productivity (GPP) and ecosystem respiration globally across a wide range of ecosystems. We show that heat extremes typically increased mainly respiration whereas drought decreased both fluxes. Combined heat and drought extremes had opposing effects offsetting each other for respiration, but there were also strong reductions in GPP and hence the strongest reductions in the ecosystems carbon sink capacity.
Miguel D. Mahecha, Fabian Gans, Sebastian Sippel, Jonathan F. Donges, Thomas Kaminski, Stefan Metzger, Mirco Migliavacca, Dario Papale, Anja Rammig, and Jakob Zscheischler
Biogeosciences, 14, 4255–4277,Short summary
We investigate the likelihood of ecological in situ networks to detect and monitor the impact of extreme events in the terrestrial biosphere.
Jakob Zscheischler, Miguel D. Mahecha, Valerio Avitabile, Leonardo Calle, Nuno Carvalhais, Philippe Ciais, Fabian Gans, Nicolas Gruber, Jens Hartmann, Martin Herold, Kazuhito Ichii, Martin Jung, Peter Landschützer, Goulven G. Laruelle, Ronny Lauerwald, Dario Papale, Philippe Peylin, Benjamin Poulter, Deepak Ray, Pierre Regnier, Christian Rödenbeck, Rosa M. Roman-Cuesta, Christopher Schwalm, Gianluca Tramontana, Alexandra Tyukavina, Riccardo Valentini, Guido van der Werf, Tristram O. West, Julie E. Wolf, and Markus Reichstein
Biogeosciences, 14, 3685–3703,Short summary
Here we synthesize a wide range of global spatiotemporal observational data on carbon exchanges between the Earth surface and the atmosphere. A key challenge was to consistently combining observational products of terrestrial and aquatic surfaces. Our primary goal is to identify today’s key uncertainties and observational shortcomings that would need to be addressed in future measurement campaigns or expansions of in situ observatories.
Jakob Zscheischler, Rene Orth, and Sonia I. Seneviratne
Biogeosciences, 14, 3309–3320,Short summary
We use newly established methods to compute bivariate return periods of temperature and precipitation and relate those to crop yield variability in Europe. Most often, crop yields are lower when it is hot and dry and higher when it is cold and wet. The variability in crop yields along a specific climate gradient can be captured well by return periods aligned with these gradients. This study provides new possibilities for investigating the relationship between crop yield variability and climate.
Emanuele Bevacqua, Douglas Maraun, Ingrid Hobæk Haff, Martin Widmann, and Mathieu Vrac
Hydrol. Earth Syst. Sci., 21, 2701–2723,Short summary
We develop a conceptual model to quantify the risk of compound events (CEs), i.e. extreme impacts to society which are driven by statistically dependent climatic variables. Based on this model we study compound floods, i.e. joint storm surge and high river level, in Ravenna (Italy). The model includes meteorological predictors which (1) provide insight into the physical processes underlying CEs, as well as into the temporal variability, and (2) allow us to statistically downscale CEs.
Sebastian Sippel, Jakob Zscheischler, Miguel D. Mahecha, Rene Orth, Markus Reichstein, Martha Vogel, and Sonia I. Seneviratne
Earth Syst. Dynam., 8, 387–403,Short summary
The present study (1) evaluates land–atmosphere coupling in the CMIP5 multi-model ensemble against an ensemble of benchmarking datasets and (2) refines the model ensemble using a land–atmosphere coupling diagnostic as constraint. Our study demonstrates that a considerable fraction of coupled climate models overemphasize warm-season
moisture-limitedclimate regimes in midlatitude regions. This leads to biases in daily-scale temperature extremes, which are alleviated in a constrained ensemble.
Francesco Avanzi, Alberto Bianchi, Alberto Cina, Carlo De Michele, Paolo Maschio, Diana Pagliari, Daniele Passoni, Livio Pinto, Marco Piras, and Lorenzo Rossi
The Cryosphere Discuss.,
Revised manuscript not acceptedShort summary
We compare three different instruments used to collect snow depth, i.e., photogrammetric surveys using Unmanned Aerial Systems (UAS), a 3D laser scanning, and manual probing. The relatively high density of manual data (135 pt over 6700 m2, i.e., 2 pt/100 m2) enables to assess the performance of UAS in capturing the marked spatial variability of snow. Results suggest that UAS represent a competitive choice among existing techniques for high-precision, high-resolution remote sensing of snow.
Sebastian Sippel, Jakob Zscheischler, Martin Heimann, Holger Lange, Miguel D. Mahecha, Geert Jan van Oldenborgh, Friederike E. L. Otto, and Markus Reichstein
Hydrol. Earth Syst. Sci., 21, 441–458,Short summary
The paper re-investigates the question whether observed precipitation extremes and annual totals have been increasing in the world's dry regions over the last 60 years. Despite recently postulated increasing trends, we demonstrate that large uncertainties prevail due to (1) the choice of dryness definition and (2) statistical data processing. In fact, we find only minor (and only some significant) increases if (1) dryness is based on aridity and (2) statistical artefacts are accounted for.
Francesco Avanzi, Hiroyuki Hirashima, Satoru Yamaguchi, Takafumi Katsushima, and Carlo De Michele
The Cryosphere, 10, 2013–2026,Short summary
We investigate capillary barriers and preferential flow in layered snow during nine cold laboratory experiments. The dynamics of each sample were replicated solving Richards equation within the 1-D multi-layer physically based SNOWPACK model. Results show that both processes affect the speed of water infiltration in stratified snow and are marked by a high degree of spatial variability at cm scale and complex 3-D patterns.
Bjorn-Gustaf J. Brooks, Ankur R. Desai, Britton B. Stephens, Anna M. Michalak, and Jakob Zscheischler
Manuscript not accepted for further reviewShort summary
CO2 is the primary greenhouse gas, and its abundance in the atmosphere tends to increase during disturbances like drought. This paper demonstrates how CO2 measurements are combined with models to determine not only how strongly different locations influence CO2 measurement stations, but also the capacity of those measurement stations to detect drought effects. Understanding detection sensitivity will help assess what kinds of changes and turnings points can be monitored using atmospheric CO2.
Carlo De Michele, Francesco Avanzi, Daniele Passoni, Riccardo Barzaghi, Livio Pinto, Paolo Dosso, Antonio Ghezzi, Roberto Gianatti, and Giacomo Della Vedova
The Cryosphere, 10, 511–522,Short summary
We investigate snow depth distribution at peak accumulation over a small Alpine area using photogrammetry-based surveys with a fixed wing unmanned aerial system. Results reveal that UAS estimations of point snow depth present an average difference with reference to manual measurements equal to -0.073 m. Moreover, in this case study snow depth standard deviation (hence coefficient of variation) increases with decreasing cell size, but it stabilizes for resolutions smaller than 1 m.
P. Licznar, C. De Michele, and W. Adamowski
Hydrol. Earth Syst. Sci., 19, 485–506,
P. Da Ronco and C. De Michele
Hydrol. Earth Syst. Sci., 18, 4579–4600,Short summary
The negative impacts of cloud obstruction in snow mapping from MODIS and a new reliable cloud removal procedure for the Italian Alps.
T. Alberti, F. Lepreti, A. Vecchio, E. Bevacqua, V. Capparelli, and V. Carbone
Clim. Past, 10, 1751–1762,
J. Zscheischler, M. Reichstein, S. Harmeling, A. Rammig, E. Tomelleri, and M. D. Mahecha
Biogeosciences, 11, 2909–2924,
J. v. Buttlar, J. Zscheischler, and M. D. Mahecha
Nonlin. Processes Geophys., 21, 203–215,
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Simon K. Allen, Ashim Sattar, Owen King, Guoqing Zhang, Atanu Bhattacharya, Tandong Yao, and Tobias Bolch
Nat. Hazards Earth Syst. Sci., 22, 3765–3785,Short summary
This study demonstrates how the threat of a very large outburst from a future lake can be feasibly assessed alongside that from current lakes to inform disaster risk management within a transboundary basin between Tibet and Nepal. Results show that engineering measures and early warning systems would need to be coupled with effective land use zoning and programmes to strengthen local response capacities in order to effectively reduce the risk associated with current and future outburst events.
Markéta Součková, Roman Juras, Kryštof Dytrt, Vojtěch Moravec, Johanna Ruth Blöcher, and Martin Hanel
Nat. Hazards Earth Syst. Sci., 22, 3501–3525,Short summary
Avalanches are natural hazards that threaten people and infrastructure. With climate change, avalanche activity is changing. We analysed the change in frequency and size of avalanches in the Krkonoše Mountains, Czechia, and detected important variables with machine learning tools from 1979–2020. Wet avalanches in February and March have increased, and slab avalanches have decreased and become smaller. The identified variables and their threshold levels may help in avalanche decision-making.
Annalie Dorph, Erica Marshall, Kate A. Parkins, and Trent D. Penman
Nat. Hazards Earth Syst. Sci., 22, 3487–3499,Short summary
Wildfire spatial patterns are determined by fire ignition sources and vegetation fuel moisture. Fire ignitions can be mediated by humans (owing to proximity to human infrastructure) or caused by lightning (owing to fuel moisture, average annual rainfall and local weather). When moisture in dead vegetation is below 20 % the probability of a wildfire increases. The results of this research enable accurate spatial mapping of ignition probability to aid fire suppression efforts and future research.
John Sykes, Pascal Haegeli, and Yves Bühler
Nat. Hazards Earth Syst. Sci., 22, 3247–3270,Short summary
Automated snow avalanche terrain mapping provides an efficient method for large-scale assessment of avalanche hazards, which informs risk management decisions for transportation and recreation. This research reduces the cost of developing avalanche terrain maps by using satellite imagery and open-source software as well as improving performance in forested terrain. The research relies on local expertise to evaluate accuracy, so the methods are broadly applicable in mountainous regions worldwide.
Ivana Čavlina Tomašević, Kevin K. W. Cheung, Višnjica Vučetić, Paul Fox-Hughes, Kristian Horvath, Maja Telišman Prtenjak, Paul J. Beggs, Barbara Malečić, and Velimir Milić
Nat. Hazards Earth Syst. Sci., 22, 3143–3165,Short summary
One of the most severe and impactful urban wildfire events in Croatian history has been reconstructed and analyzed. The study identified some important meteorological influences related to the event: the synoptic conditions of the Azores anticyclone, cold front, and upper-level shortwave trough all led to the highest fire weather index in 2017. A low-level jet, locally known as bura wind that can be explained by hydraulic jump theory, was the dynamic trigger of the event.
Adam Emmer, Simon K. Allen, Mark Carey, Holger Frey, Christian Huggel, Oliver Korup, Martin Mergili, Ashim Sattar, Georg Veh, Thomas Y. Chen, Simon J. Cook, Mariana Correas-Gonzalez, Soumik Das, Alejandro Diaz Moreno, Fabian Drenkhan, Melanie Fischer, Walter W. Immerzeel, Eñaut Izagirre, Ramesh Chandra Joshi, Ioannis Kougkoulos, Riamsara Kuyakanon Knapp, Dongfeng Li, Ulfat Majeed, Stephanie Matti, Holly Moulton, Faezeh Nick, Valentine Piroton, Irfan Rashid, Masoom Reza, Anderson Ribeiro de Figueiredo, Christian Riveros, Finu Shrestha, Milan Shrestha, Jakob Steiner, Noah Walker-Crawford, Joanne L. Wood, and Jacob C. Yde
Nat. Hazards Earth Syst. Sci., 22, 3041–3061,Short summary
Glacial lake outburst floods (GLOFs) have attracted increased research attention recently. In this work, we review GLOF research papers published between 2017 and 2021 and complement the analysis with research community insights gained from the 2021 GLOF conference we organized. The transdisciplinary character of the conference together with broad geographical coverage allowed us to identify progress, trends and challenges in GLOF research and outline future research needs and directions.
Fátima Arrogante-Funes, Inmaculada Aguado, and Emilio Chuvieco
Nat. Hazards Earth Syst. Sci., 22, 2981–3003,Short summary
We show that ecological value might be reduced by 50 % due to fire perturbation in ecosystems that have not developed in the presence of fire and/or that present changes in the fire regime. The biomes most affected are tropical and subtropical forests, tundra, and mangroves. Integration of biotic and abiotic fire regime and regeneration factors resulted in a powerful way to map ecological vulnerability to fire and develop assessments to generate adaptation plans of management in forest masses.
Aubrey Miller, Pascal Sirguey, Simon Morris, Perry Bartelt, Nicolas Cullen, Todd Redpath, Kevin Thompson, and Yves Bühler
Nat. Hazards Earth Syst. Sci., 22, 2673–2701,Short summary
Natural hazard modelers simulate mass movements to better anticipate the risk to people and infrastructure. These simulations require accurate digital elevation models. We test the sensitivity of a well-established snow avalanche model (RAMMS) to the source and spatial resolution of the elevation model. We find key differences in the digital representation of terrain greatly affect the simulated avalanche results, with implications for hazard planning.
Kathryn C. Fisher, Pascal Haegeli, and Patrick Mair
Nat. Hazards Earth Syst. Sci., 22, 1973–2000,Short summary
Avalanche bulletins include travel and terrain statements to provide recreationists with tangible guidance about how to apply the hazard information. We examined which bulletin users pay attention to these statements, what determines their usefulness, and how they could be improved. Our study shows that reducing jargon and adding simple explanations can significantly improve the usefulness of the statements for users with lower levels of avalanche awareness education who depend on this advice.
Cristina Pérez-Guillén, Frank Techel, Martin Hendrick, Michele Volpi, Alec van Herwijnen, Tasko Olevski, Guillaume Obozinski, Fernando Pérez-Cruz, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 22, 2031–2056,Short summary
A fully data-driven approach to predicting the danger level for dry-snow avalanche conditions in Switzerland was developed. Two classifiers were trained using a large database of meteorological data, snow cover simulations, and danger levels. The models performed well throughout the Swiss Alps, reaching a performance similar to the current experience-based avalanche forecasts. This approach shows the potential to be a valuable supplementary decision support tool for assessing avalanche hazard.
Michael A. Storey and Owen F. Price
Models are needed to understand and predict pollutant output from forest fires so fire agencies can reduce smoke-related risks to human health. We modelled air quality (PM2.5) based on fire area and weather variables. We found fire area and boundary layer height were influential predictors, with distance, temperature, wind speed and relative humidity also important. The model predicted reasonably accurately in comparison to other existing methods, but would benefit from further development.
Frank Techel, Stephanie Mayer, Cristina Pérez-Guillén, Günter Schmudlach, and Kurt Winkler
Nat. Hazards Earth Syst. Sci., 22, 1911–1930,Short summary
Can the resolution of forecasts of avalanche danger be increased by using a combination of absolute and comparative judgments? Using 5 years of Swiss avalanche forecasts, we show that, on average, sub-levels assigned to a danger level reflect the expected increase in the number of locations with poor snow stability and in the number and size of avalanches with increasing forecast sub-level.
Yves Bühler, Peter Bebi, Marc Christen, Stefan Margreth, Lukas Stoffel, Andreas Stoffel, Christoph Marty, Gregor Schmucki, Andrin Caviezel, Roderick Kühne, Stephan Wohlwend, and Perry Bartelt
Nat. Hazards Earth Syst. Sci., 22, 1825–1843,Short summary
To calculate and visualize the potential avalanche hazard, we develop a method that automatically and efficiently pinpoints avalanche starting zones and simulate their runout for the entire canton of Grisons. The maps produced in this way highlight areas that could be endangered by avalanches and are extremely useful in multiple applications for the cantonal authorities, including the planning of new infrastructure, making alpine regions more safe.
Ana C. L. Sá, Bruno A. Aparicio, Akli Benali, Chiara Bruni, Michele Salis, Fábio Silva, Martinho Marta-Almeida, Susana Pereira, Alfredo Rocha, and José M. C. Pereira
Nat. Hazards Earth Syst. Sci. Discuss.,
Revised manuscript accepted for NHESSShort summary
Assessing landscape wildfire connectivity supported by wildfire spread simulations can improve fire hazard assessment and fuel management plans. Weather severity determines the degree of fuel patches connectivity, and thus the potential to spread large and intense wildfires. Mapping highly connected patches in the landscape highlights patch candidates for prior fuel treatments, which ultimately will contribute to create fire-resilient Mediterranean landscapes.
Tero M. Partanen and Mikhail Sofiev
Nat. Hazards Earth Syst. Sci., 22, 1335–1346,Short summary
The presented method aims to forecast regional wildfire-emitted radiative power in a time-dependent manner several days in advance. The temporal fire radiative power can be converted to an emission production rate, which can be implemented in air quality forecasting simulations. It is shown that in areas with a high incidence of wildfires, the fire radiative power is quite predictable, but otherwise it is not.
Christos Bountzouklis, Dennis M. Fox, and Elena Di Bernardino
Nat. Hazards Earth Syst. Sci., 22, 1181–1200,Short summary
The study addresses the evolution of burned areas in southeastern France from 1970 to 2019 through the scope of a firefighting policy shift in 1994 that resulted in a significant decrease in the burned area. Regions with large fires were particularly impacted, whereas, in other areas, the fires remained frequent and occurred closer to built-up zones. Environmental characteristics such as south-facing slopes and low vegetation (bushes) are increasingly associated with burned areas.
Louis Védrine, Xingyue Li, and Johan Gaume
Nat. Hazards Earth Syst. Sci., 22, 1015–1028,Short summary
This study investigates how forests affect the behaviour of snow avalanches through the evaluation of the amount of snow stopped by the trees and the analysis of energy dissipation mechanisms. Different avalanche features and tree configurations have been examined, leading to the proposal of a unified law for the detrained snow mass. Outcomes from this study can be directly implemented in operational models for avalanche risk assessment and contribute to improved forest management strategy.
Matthew C. Perry, Emilie Vanvyve, Richard A. Betts, and Erika J. Palin
Nat. Hazards Earth Syst. Sci., 22, 559–575,Short summary
In the past, wildfires in the UK have occurred mainly in spring, with occasional events during hot, dry summers. Climate models predict a large future increase in hazardous fire weather conditions in summer. Wildfire can be considered an
emergent riskfor the UK, as past events have not had widespread major impacts, but this could change. The large increase in risk between the 2 °C and 4 °C levels of global warming highlights the importance of global efforts to keep warming below 2 °C.
Philip A. Ebert and Peter Milne
Nat. Hazards Earth Syst. Sci., 22, 539–557,Short summary
There is no consensus about how to assess the quality of binary (yes or no) rare and severe event forecasts, i.e. forecasts involving natural hazards like tornadoes or avalanches. We offer a comprehensive overview of the challenges we face when making such an assessment and provide a critical review of existing solutions. We argue against all but one existing solution to assess the quality of such forecasts and present practical consequences to improve forecasting services.
Jacques Mourey, Pascal Lacroix, Pierre-Allain Duvillard, Guilhem Marsy, Marco Marcer, Emmanuel Malet, and Ludovic Ravanel
Nat. Hazards Earth Syst. Sci., 22, 445–460,Short summary
More frequent rockfalls in high alpine environments due to climate change are a growing threat to mountaineers. This hazard is particularly important on the classic route up Mont Blanc. Our results show that rockfalls are most frequent during snowmelt periods and the warmest hours of the day, and that mountaineers do not adapt to the local rockfall hazard when planning their ascent. Disseminating the knowledge acquired from our study caused management measures to be implemented for the route.
Tomàs Artés, Marc Castellnou, Tracy Houston Durrant, and Jesús San-Miguel
Nat. Hazards Earth Syst. Sci., 22, 509–522,Short summary
During the last 20 years extreme wildfires have challenged firefighting capabilities. Several fire danger indices are routinely used by firefighting services but are not suited to forecast convective extreme wildfire behaviour at the global scale. This article proposes a new fire danger index for deep moist convection, the extreme-fire behaviour index (EFBI), based on the analysis of the vertical profiles of the atmosphere above wildfires to use along with traditional fire danger indices.
Veronika Hutter, Frank Techel, and Ross S. Purves
Nat. Hazards Earth Syst. Sci., 21, 3879–3897,Short summary
How is avalanche danger described in public avalanche forecasts? We analyzed 6000 textual descriptions of avalanche danger in Switzerland, taking the perspective of the forecaster. Avalanche danger was described rather consistently, although the results highlight the difficulty of communicating conditions that are neither rare nor frequent, neither small nor large. The study may help to refine the ways in which avalanche danger could be communicated to the public.
Edilia Jaque Castillo, Alfonso Fernández, Rodrigo Fuentes Robles, and Carolina G. Ojeda
Nat. Hazards Earth Syst. Sci., 21, 3663–3678,Short summary
Wildfires pose risks to lives and livelihoods in many regions of the world. Particularly in Chile's central-south region, climate change, widespread land use change, and urban growth tend to increase the likelihood of fire occurrence. Our work focused on the Concepción metropolitan area, where we developed a model using machine learning in order to map wildfire risks. We found that the interface between urban areas and forestry plantations presents the highest risks.
Alessandro Gattuso, Francesco Italiano, Giorgio Capasso, Antonino D'Alessandro, Fausto Grassa, Antonino Fabio Pisciotta, and Davide Romano
Nat. Hazards Earth Syst. Sci., 21, 3407–3419,Short summary
Santa Barbara and Aragona are affected by mud volcanism with episodic hazardous paroxysm events. Two potentially hazardous paroxysm exposed surfaces of 0.12 and 0.20 km2 were elaborated with DSMs and with historical information on the paroxysms that occurred in the past. This paper, in the end, could be a useful tool for civil protection authorities in order to take appropriate risk mitigation measurements for exposed people and for monitoring activities.
Kathryn C. Fisher, Pascal Haegeli, and Patrick Mair
Nat. Hazards Earth Syst. Sci., 21, 3219–3242,Short summary
Avalanche warning services publish condition reports to help backcountry recreationists make informed decisions about when and where to travel in avalanche terrain. We tested how different graphic representations of terrain information can affect users’ ability to interpret and apply the provided information. Our study shows that a combined presentation of aspect and elevation information is the most effective. These results can be used to improve avalanche risk communication products.
Jeffrey Katan and Liliana Perez
Nat. Hazards Earth Syst. Sci., 21, 3141–3160,Short summary
Wildfires are an integral part of ecosystems worldwide, but they also pose a serious risk to human life and property. To further our understanding of wildfires and allow experimentation without recourse to live fires, this study presents an agent-based modelling approach to combine the complexity possible with physical models with the ease of computation of empirical models. Model calibration and validation show bottom-up simulation tracks the core elements of complexity of fire across scales.
Xiaowen Wang, Lin Liu, Yan Hu, Tonghua Wu, Lin Zhao, Qiao Liu, Rui Zhang, Bo Zhang, and Guoxiang Liu
Nat. Hazards Earth Syst. Sci., 21, 2791–2810,Short summary
We characterized the multi-decadal geomorphic changes of a low-angle valley glacier in the East Kunlun Mountains and assessed the detachment hazard influence. The observations reveal a slow surge-like dynamic pattern of the glacier tongue. The maximum runout distances of two endmember avalanche scenarios were presented. This study provides a reference to evaluate the runout hazards of low-angle mountain glaciers prone to detachment.
Xuguo Shi, Shaocheng Zhang, Mi Jiang, Yuanyuan Pei, Tengteng Qu, Jinhu Xu, and Chen Yang
Nat. Hazards Earth Syst. Sci., 21, 2285–2297,Short summary
We mapped the subsidence of Wuhan using Sentinel-1 synthetic aperture radar (SAR) images acquired during 2015–2019. Overall subsidence coincides with the distribution of engineered geological regions with soft soils, while the subsidence centers shifted with urban construction activities. Correlation between karst subsidence and concentrated rainfall was identified in Qingling–Jiangdi. Results indicate that interferometric SAR can be employed to routinely monitor and identify geohazards.
Mirlan Daiyrov and Chiyuki Narama
Nat. Hazards Earth Syst. Sci., 21, 2245–2256,Short summary
In the Teskey Range of the Tien Shan (Kyrgyz Republic), four outburst flood disasters from short-lived glacial lakes in 2006, 2008, 2013, and 2014 caused severe damages in the downstream part. Short-lived glacial lakes grow rapidly and drain within a few months, due to closure and opening of an outlet ice tunnel in an ice-cored moraine complex at the glacier front. We investigated how short-lived glacial lakes store and drain water over short periods based on field survey and satellite data.
Tomás Calheiros, Akli Benali, João Neves Silva, Mário Pereira, and João Pedro Nunes
Nat. Hazards Earth Syst. Sci. Discuss.,
Revised manuscript accepted for NHESSShort summary
Fire weather indices are used to assess the effect of weather on wildfires and are strongly related to burnt area in Portugal. Fire weather risk was computed and combined with large wildfires. Results revealed the influence of vegetation cover: municipalities with prevalence of shrublands, located in eastern parts, burnt with less extreme conditions than those with higher forested areas, situated in coastal regions. These findings can support better prevention and fire suppression planning.
Kerstin Wegner, Florian Haas, Tobias Heckmann, Anne Mangeney, Virginie Durand, Nicolas Villeneuve, Philippe Kowalski, Aline Peltier, and Michael Becht
Nat. Hazards Earth Syst. Sci., 21, 1159–1177,Short summary
In mountainous regions rockfall is a common geomorphic process. We selected four study sites that feature different rock types. High-resolution terrestrial laser scanning data were acquired to measure the block size and block shape (axial ratio) of rockfall particles on the scree deposits. Laser scanning data were also used to characterize the morphology of these landforms. Our results show that hill slope and rock particle properties govern rock particle runout in a complex manner.
Eszter Szűcs, Sándor Gönczy, István Bozsó, László Bányai, Alexandru Szakacs, Csilla Szárnya, and Viktor Wesztergom
Nat. Hazards Earth Syst. Sci., 21, 977–993,Short summary
Sinkhole formation and post-collapse deformation in the Solotvyno salt mining area was studied where the salt dissolution due to water intrusion poses a significant risk. Based on a Sentinel-1 data set, remarkable surface deformation with a maximum rate of 5 cm/yr was revealed, and it was demonstrated that the deformation process has a linear characteristic although the mining activity was ended more than 10 years ago.
Geert Jan van Oldenborgh, Folmer Krikken, Sophie Lewis, Nicholas J. Leach, Flavio Lehner, Kate R. Saunders, Michiel van Weele, Karsten Haustein, Sihan Li, David Wallom, Sarah Sparrow, Julie Arrighi, Roop K. Singh, Maarten K. van Aalst, Sjoukje Y. Philip, Robert Vautard, and Friederike E. L. Otto
Nat. Hazards Earth Syst. Sci., 21, 941–960,Short summary
Southeastern Australia suffered from disastrous bushfires during the 2019/20 fire season, raising the question whether these have become more likely due to climate change. We found no attributable trend in extreme annual or monthly low precipitation but a clear shift towards more extreme heat. However, this shift is underestimated by the models. Analysing fire weather directly, we found that the chance has increased by at least 30 %, but due to the underestimation it could well be higher.
Andrew R. Schauer, Jordy Hendrikx, Karl W. Birkeland, and Cary J. Mock
Nat. Hazards Earth Syst. Sci., 21, 757–774,Short summary
Our research links upper atmospheric circulation patterns to a destructive and difficult-to-predict type of snow avalanche in the western United States. At each of our study sites, we find unique circulation patterns that tend to occur at the beginning of the winter season during years with major avalanche activity. We also find specific patterns that occur frequently in the days leading to major avalanche events. This work will enable practitioners to better anticipate these challenging events.
Erich Peitzsch, Jordy Hendrikx, Daniel Stahle, Gregory Pederson, Karl Birkeland, and Daniel Fagre
Nat. Hazards Earth Syst. Sci., 21, 533–557,Short summary
We sampled 647 trees from 12 avalanche paths to investigate large snow avalanches over the past 400 years in the northern Rocky Mountains, USA. Sizable avalanches occur approximately every 3 years across the region. Our results emphasize the importance of sample size, scale, and spatial extent when reconstructing avalanche occurrence across a region. This work can be used for infrastructure planning and avalanche forecasting operations.
Simon Horton, Moses Towell, and Pascal Haegeli
Nat. Hazards Earth Syst. Sci., 20, 3551–3576,Short summary
We investigate patterns in how avalanche forecasters characterize snow avalanche hazard with avalanche problem types. Decision tree analysis was used to investigate both physical influences based on weather and on snowpack variables and operational practices. The results highlight challenges with developing decision aids based on previous hazard assessments.
Dan K. Thompson and Kimberly Morrison
Nat. Hazards Earth Syst. Sci., 20, 3439–3454,Short summary
We describe critically low relative humidity and high wind speeds above which only documented wildfires were seen to occur and where no agricultural fires were documented in southern Canada. We then applied these thresholds to the much larger satellite record from 2002–2018 to quantify regional differences in both the rate of observed burning and the number of days with critical weather conditions to sustain a wildfire in this grassland and agricultural region.
Chuanguang Zhu, Wenhao Wu, Mahdi Motagh, Liya Zhang, Zongli Jiang, and Sichun Long
Nat. Hazards Earth Syst. Sci., 20, 3399–3411,Short summary
We investigate the contemporary ground deformation along the RLHR-HZ using Sentinel-1 data and find that the RLHR-HZ runs through two main subsidence areas. A total length of 35 km of the RLSR-HZ is affected by the two subsidence basins. Considering the previous investigation coupled with information on human activities, we conclude that the subsidence is mainly caused by extraction of groundwater and underground mining.
Negar Ghahramani, Andrew Mitchell, Nahyan M. Rana, Scott McDougall, Stephen G. Evans, and W. Andy Take
Nat. Hazards Earth Syst. Sci., 20, 3425–3438,Short summary
Tailings flows result from the breach of tailings dams. These flows contain waste products of the mineral processing operations and can travel substantial distances, causing significant loss of life, environmental damage, and economic costs. This paper establishes a new tailings-flow runout classification system, describes a new database of events that have been mapped in detail using the new system, and examines the applicability of a semi-physical area–volume relationship using the new data.
Tae-Young Kwak, Sang-Inn Woo, Choong-Ki Chung, and Joonyoung Kim
Nat. Hazards Earth Syst. Sci., 20, 3343–3359,Short summary
In this study, model tests were used to analyze the effects of rainfall intensity on the formation of the eroded zone and the occurrence of sinkholes due to groundwater infiltration through pipe defects. The model tests were conducted to simulate the actual site conditions considering the soil used around sewer pipe networks and the sewer pipe landfill standards. The groundwater level was applied to the model tests by setting three hydraulic heads based on heavy-rainfall characteristics.
Erwan Le Roux, Guillaume Evin, Nicolas Eckert, Juliette Blanchet, and Samuel Morin
Nat. Hazards Earth Syst. Sci., 20, 2961–2977,Short summary
To minimize the risk of structure collapse due to extreme snow loads, structure standards rely on 50-year return levels of ground snow load (GSL), i.e. levels exceeded once every 50 years on average, that do not account for climate change. We study GSL data in the French Alps massifs from 1959 and 2019 and find that these 50-year return levels are decreasing with time between 900 and 4800 m of altitude, but they still exceed return levels of structure standards for half of the massifs at 1800 m.
Bettina Richter, Alec van Herwijnen, Mathias W. Rotach, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 20, 2873–2888,Short summary
We investigated the sensitivity of modeled snow instability to uncertainties in meteorological input, typically found in complex terrain. The formation of the weak layer was very robust due to the long dry period, indicated by a widespread avalanche problem. Once a weak layer has formed, precipitation mostly determined slab and weak layer properties and hence snow instability. When spatially assessing snow instability for avalanche forecasting, accurate precipitation patterns have to be known.
Francesca Di Giuseppe, Claudia Vitolo, Blazej Krzeminski, Christopher Barnard, Pedro Maciel, and Jesús San-Miguel
Nat. Hazards Earth Syst. Sci., 20, 2365–2378,Short summary
Forecasting of daily fire weather indices driven by the ECMWF ensemble prediction system is shown to have a good skill up to 10 d ahead in predicting flammable conditions in most regions of the world. The availability of these forecasts through the Copernicus Emergency Management Service can extend early warnings by up to 1–2 weeks, allowing for greater proactive coordination of resource-sharing and mobilization within and across countries.
Andrea Franco, Jasper Moernaut, Barbara Schneider-Muntau, Michael Strasser, and Bernhard Gems
Nat. Hazards Earth Syst. Sci., 20, 2255–2279,Short summary
This study highlights the use of the software Flow-3D in reproducing landslide-generated impulse waves. Due to the available data and the possibility of comparing the results with other previous works, a numerical modelling investigation on the 1958 Lituya Bay tsunami event is proposed. It is noted that the rockslide impact into the waterbody has a key role in the wave initiation and thus its propagation. The concept used in this work can be applied to prevent such phenomena in future.
Frank Techel, Kurt Winkler, Matthias Walcher, Alec van Herwijnen, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 20, 1941–1953,Short summary
Snow instability tests, like the extended column test (ECT), provide valuable information regarding point snow instability. A large data set of ECT – together with information on slope instability – was explored. The findings clearly show that combining information regarding propagation propensity and fracture initiation provided the best correlation with slope instability. A new four-class stability interpretation scheme is proposed for ECT results.
Silvan Leinss, Raphael Wicki, Sämi Holenstein, Simone Baffelli, and Yves Bühler
Nat. Hazards Earth Syst. Sci., 20, 1783–1803,Short summary
To assess snow avalanche mapping with radar satellites in Switzerland, we compare 2 m resolution TerraSAR-X images, 10 m resolution Sentinel-1 images, and optical 1.5 m resolution SPOT-6 images. We found that radar satellites provide a valuable option to map at least larger avalanches, though avalanches are mapped only partially. By combining multiple orbits and polarizations from S1, we achieved mapping results of quality almost comparable to single high-resolution TerraSAR-X images.
Mercy N. Ndalila, Grant J. Williamson, Paul Fox-Hughes, Jason Sharples, and David M. J. S. Bowman
Nat. Hazards Earth Syst. Sci., 20, 1497–1511,Short summary
We analyse the evolution of a pyrocumulonimbus (pyroCb), or fire-induced thunderstorm, during the Forcett–Dunalley fire on 4 January 2013 and relate it to the prevailing fire weather and fire severity patterns. We show that the pyroCb reached an altitude of 15 km, was associated with elevated fire weather, and formed over a severely burned area. Additionally, we show that eastern Tasmania is prone to elevated fire weather which has implications for fire weather forecasting and fire management.
Robert D. Field
Nat. Hazards Earth Syst. Sci., 20, 1123–1147,Short summary
This paper compares fire weather indices calculated from the NASA MERRA-2 reanlaysis to those calculated from a global network of weather stations, finding that, globally, biases in reanalysis fire weather are influenced firstly by temperature and relative humidity and, in certain regions, by precipitation biases. Fire weather forecasts using short-term NASA GEOS-5 weather forecasts are skillful 2 d ahead of time. This skill decreases more quickly with longer lead times at high latitudes.
Alireza Farahmand, E. Natasha Stavros, John T. Reager, Ali Behrangi, James T. Randerson, and Brad Quayle
Nat. Hazards Earth Syst. Sci., 20, 1097–1106,Short summary
Wildfires result in billions of dollars of losses each year. Most wildfire predictions have a 10 d lead-time. This study introduces a framework for a 1-month lead-time prediction of wildfires based on vapor pressure deficit and surface soil moisture in the US. The results show that the model can successfully predict burned area with relatively small margins of error. This is especially important for operational wildfire management such as national resource allocation.
Holt Hancock, Markus Eckerstorfer, Alexander Prokop, and Jordy Hendrikx
Nat. Hazards Earth Syst. Sci., 20, 603–623,Short summary
This work uses terrestrial laser scanning techniques to monitor and quantify changes to snow cornices near Longyearbyen, Svalbard, Norway, with sub-decimeter accuracy. Our findings illustrate how complex interactions between topography and meteorological conditions govern the growth, failure, and associated avalanche activity of the cornices in this location. These findings can help improve forecasting of snow-cornice-related hazards in this and other locations exposed to snow cornice hazards.
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Climate hazards may be caused by events which have multiple drivers. Here we present a method to break down climate model biases in hazard indicators down to the bias caused by each driving variable. Using simplified fire and heat stress indicators driven by temperature and relative humidity as examples, we show how multivariate indicators may have complex biases and that the relationship between driving variables is a source of bias that must be considered in climate model bias corrections.
Climate hazards may be caused by events which have multiple drivers. Here we present a method to...