Articles | Volume 17, issue 5
https://doi.org/10.5194/nhess-17-749-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/nhess-17-749-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
22 May 2017
Research article |
| 22 May 2017
Anomalous winter-snow-amplified earthquake-induced disaster of the 2015 Langtang avalanche in Nepal
Graduate School of Environmental Studies, Nagoya University, Nagoya,
Japan
Hiroshi Inoue
Disaster Risk Research Unit, National Research Institute for Earth
Science and Disaster Resilience, Tsukuba, Japan
Takeki Izumi
Graduate School of Urban Environmental Sciences, Tokyo Metropolitan
University, Hachioji, Japan
Satoru Yamaguchi
Snow and Ice Research Center, National Research Institute for Earth
Science and Disaster Resilience, Nagaoka, Japan
Ayako Sadakane
Langtang Plan, Kamakura, Japan
Sojiro Sunako
Graduate School of Environmental Studies, Nagoya University, Nagoya,
Japan
Kouichi Nishimura
Graduate School of Environmental Studies, Nagoya University, Nagoya,
Japan
Walter W. Immerzeel
Department of Physical Geography, Faculty of Geosciences, Utrecht
University, Utrecht, the Netherlands
International Centre for Integrated Mountain Development, Khumaltar,
Kathmandu, Nepal
Joseph M. Shea
International Centre for Integrated Mountain Development, Khumaltar,
Kathmandu, Nepal
Centre for Hydrology, University of Saskatchewan, Saskatoon,
Canada
Rijan B. Kayastha
School of Science, Kathmandu University, Kathmandu, Nepal
Takanobu Sawagaki
Faculty of Social Sciences, Hosei University, Tokyo, Japan
David F. Breashears
GlacierWorks, Marblehead, MA, USA
Hiroshi Yagi
Faculty of Education, Art and Science, Yamagata University, Yamagata,
Japan
Akiko Sakai
Graduate School of Environmental Studies, Nagoya University, Nagoya,
Japan
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T. Nuimura, A. Sakai, K. Taniguchi, H. Nagai, D. Lamsal, S. Tsutaki, A. Kozawa, Y. Hoshina, S. Takenaka, S. Omiya, K. Tsunematsu, P. Tshering, and K. Fujita
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A. Sakai, T. Nuimura, K. Fujita, S. Takenaka, H. Nagai, and D. Lamsal
The Cryosphere, 9, 865–880, https://doi.org/10.5194/tc-9-865-2015, https://doi.org/10.5194/tc-9-865-2015, 2015
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K. Fujita and A. Sakai
Hydrol. Earth Syst. Sci., 18, 2679–2694, https://doi.org/10.5194/hess-18-2679-2014, https://doi.org/10.5194/hess-18-2679-2014, 2014
H. Nagai, K. Fujita, T. Nuimura, and A. Sakai
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K. Fujita, A. Sakai, S. Takenaka, T. Nuimura, A. B. Surazakov, T. Sawagaki, and T. Yamanokuchi
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Y. Zhang, Y. Hirabayashi, K. Fujita, S. Liu, and Q. Liu
The Cryosphere Discuss., https://doi.org/10.5194/tcd-7-2413-2013, https://doi.org/10.5194/tcd-7-2413-2013, 2013
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Short summary
Monthly ice core records spanning 350 years from Greenland show trends in refractory black carbon (rBC) concentrations and sizes. rBC levels have increased since the 1870s due to the inflow of anthropogenic rBC, with larger diameters than those from biomass burning (BB) rBC. High summer BB rBC peaks may reduce the ice sheet albedo, but BB rBC showed no increase until the early 2000s. These results are vital for validating aerosol and climate models.
Zhao Wei, Shohei Hattori, Asuka Tsuruta, Zhuang Jiang, Sakiko Ishino, Koji Fujita, Sumito Matoba, Lei Geng, Alexis Lamothe, Ryu Uemura, Naohiro Yoshida, Joel Savarino, and Yoshinori Iizuka
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Nitrate isotope records in ice cores reveal changes in NOₓ emissions, atmospheric acidity, and oxidation chemistry driven by human activity. However, nitrate in snow can be altered by UV-driven post-depositional processes, making snow accumulation rates critical for preserving these records. This study examines nitrate isotopes in an SE-Dome ice core, where high snow accumulation minimizes these effects, providing a reliable archive of atmospheric nitrogen cycling.
Kumiko Goto-Azuma, Remi Dallmayr, Yoshimi Ogawa-Tsukagawa, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Motohiro Hirabayashi, Jun Ogata, Kyotaro Kitamura, Kenji Kawamura, Koji Fujita, Sumito Matoba, Naoko Nagatsuka, Akane Tsushima, Kaori Fukuda, and Teruo Aoki
Atmos. Chem. Phys., 24, 12985–13000, https://doi.org/10.5194/acp-24-12985-2024, https://doi.org/10.5194/acp-24-12985-2024, 2024
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We developed a continuous flow analysis system to analyze an ice core from northwestern Greenland and coupled it with an improved refractory black carbon (rBC) measurement technique. This allowed accurate high-resolution analyses of size distributions and concentrations of rBC particles with diameters of 70 nm–4 μm for the past 350 years. Our results provide crucial insights into rBC's climatic effects. We also found previous ice core studies substantially underestimated rBC mass concentrations.
Kundan Lal Shrestha, Rijan Bhakta Kayastha, and Rakesh Kayastha
Proc. IAHS, 387, 25–31, https://doi.org/10.5194/piahs-387-25-2024, https://doi.org/10.5194/piahs-387-25-2024, 2024
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The Himalayan river basins have complex terrain and lack detailed hydrological and meteorological information. This has motivated us to develop a fast and distributed model named PyGDM to simulate the hydrology of this region, which is home to both glaciers and snow. PyGDM is good at simulating glacier and snow melt. Hence, the model is suitable for studying different aspects of the Himalayan region, such as the impact of climate change and hydropower scenarios.
Rakesh Kayastha, Rijan Bhakta Kayastha, Kundan Lal Shrestha, and Smriti Gurung
Proc. IAHS, 387, 53–58, https://doi.org/10.5194/piahs-387-53-2024, https://doi.org/10.5194/piahs-387-53-2024, 2024
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We have estimated hydropower potential in the two glacierized river basins of the Nepalese Himalayas. The Glacio-hydrological Degree-Day Model (GDM) was used with different geospatial criteria. In order to force the model simulation and to assess potential future hydrological regimes, a variety of climate variables were combined and used. The sensitivity of climate variables and their impact on hydropower potential were investigated with a combination of different climate variables.
Dinesh Joshi, Rijan Bhakta Kayastha, Kundan Lal Shrestha, and Rakesh Kayastha
Proc. IAHS, 387, 17–24, https://doi.org/10.5194/piahs-387-17-2024, https://doi.org/10.5194/piahs-387-17-2024, 2024
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Glacial lake outburst flood (GLOF) modeling of Tsho Rolpa showed that, even if the lake breaches by 20 m in 40 years (from 2021), there will be a sufficient lead time of more than 7 h for early warning and human evacuations in the downstream areas. However, precautionary measures such as community-based GLOF early-warning systems and mechanisms allowing close observation in the case of GLOF events should be established in GLOF-prone regions.
Rijan Bhakta Kayastha, Hari Krishna Shrestha, and Dhiraj Pradhananga
Proc. IAHS, 387, 1–2, https://doi.org/10.5194/piahs-387-1-2024, https://doi.org/10.5194/piahs-387-1-2024, 2024
Kouichi Nishimura, Masaki Nemoto, Yoichi Ito, Satoru Omiya, Kou Shimoyama, and Hirofumi Niiya
The Cryosphere, 18, 4775–4786, https://doi.org/10.5194/tc-18-4775-2024, https://doi.org/10.5194/tc-18-4775-2024, 2024
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It is crucial to consider organized structures such as turbulence sweeps and ejections when discussing the onset and development of snow transport. This study aims to systematically measure blowing and drifting snow to investigate their spatiotemporal structures. To achieve this goal, we have deployed 15 snow particle counters (SPCs) in designated test areas and are conducting measurements using an equal number of ultrasonic anemometers, providing high-temporal-resolution data.
Orie Sasaki, Evan Stewart Miles, Francesca Pellicciotti, Akiko Sakai, and Koji Fujita
EGUsphere, https://doi.org/10.5194/egusphere-2024-2026, https://doi.org/10.5194/egusphere-2024-2026, 2024
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This study proposes a new method to detect snowline altitude (SLA) using the Google Earth Engine platform with high-resolution satellite imagery, applicable anywhere in the world. Applying this method to five glaciated watersheds in the Himalayas reveals regional consistencies and differences in snow dynamics. We also investigate the primary controls of these dynamics by analyzing climatic factors and topographic characteristics.
Léo C. P. Martin, Sebastian Westermann, Michele Magni, Fanny Brun, Joel Fiddes, Yanbin Lei, Philip Kraaijenbrink, Tamara Mathys, Moritz Langer, Simon Allen, and Walter W. Immerzeel
Hydrol. Earth Syst. Sci., 27, 4409–4436, https://doi.org/10.5194/hess-27-4409-2023, https://doi.org/10.5194/hess-27-4409-2023, 2023
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Across the Tibetan Plateau, many large lakes have been changing level during the last decades as a response to climate change. In high-mountain environments, water fluxes from the land to the lakes are linked to the ground temperature of the land and to the energy fluxes between the ground and the atmosphere, which are modified by climate change. With a numerical model, we test how these water and energy fluxes have changed over the last decades and how they influence the lake level variations.
Vigan Mensah, Koji Fujita, Stephen Howell, Miho Ikeda, Mizuki Komatsu, and Kay I. Ohshima
EGUsphere, https://doi.org/10.5194/egusphere-2023-2492, https://doi.org/10.5194/egusphere-2023-2492, 2023
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We estimated the volume of freshwater released by sea ice, glaciers, rivers, and precipitation into Baffin Bay and the Labrador Sea, and their changes over the past 70 years. We found that the freshwater volume has risen in Baffin Bay due to increased glacier melting, and dropped in the Labrador Sea because of the decline in sea ice production. We also infer that freshwater from the Arctic Ocean has been exported to our study region for the past 30 years, possibly as a result of global warming.
Motoshi Nishimura, Teruo Aoki, Masashi Niwano, Sumito Matoba, Tomonori Tanikawa, Tetsuhide Yamasaki, Satoru Yamaguchi, and Koji Fujita
Earth Syst. Sci. Data, 15, 5207–5226, https://doi.org/10.5194/essd-15-5207-2023, https://doi.org/10.5194/essd-15-5207-2023, 2023
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We presented the method of data quality checks and the dataset for two ground weather observations in northwest Greenland. We found that the warm and clear weather conditions in the 2015, 2019, and 2020 summers caused the snowmelt and the decline in surface reflectance of solar radiation at a low-elevated site (SIGMA-B; 944 m), but those were not seen at the high-elevated site (SIGMA-A; 1490 m). We hope that our data management method and findings will help climate scientists.
Yukihiko Onuma, Koji Fujita, Nozomu Takeuchi, Masashi Niwano, and Teruo Aoki
The Cryosphere, 17, 3309–3328, https://doi.org/10.5194/tc-17-3309-2023, https://doi.org/10.5194/tc-17-3309-2023, 2023
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We established a novel model that simulates the temporal changes in cryoconite hole (CH) depth using heat budgets calculated independently at the ice surface and CH bottom based on hole shape geometry. The simulations suggest that CH depth is governed by the balance between the intensity of the diffuse component of downward shortwave radiation and the wind speed. The meteorological conditions may be important factors contributing to the recent ice surface darkening via the redistribution of CHs.
Naoko Nagatsuka, Kumiko Goto-Azuma, Koji Fujita, Yuki Komuro, Motohiro Hirabayashi, Jun Ogata, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Ayaka Yonekura, Fumio Nakazawa, Yukihiko Onuma, Naoyuki Kurita, Sune Olander Rasmussen, Giulia Sinnl, Trevor James Popp, and Dorthe Dahl-Jensen
EGUsphere, https://doi.org/10.5194/egusphere-2023-1666, https://doi.org/10.5194/egusphere-2023-1666, 2023
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We present a new high-temporal-resolution record of mineral composition in a northeastern Greenland ice-core (EGRIP) over the past 100 years. The ice core dust composition and its variation differed significantly from a northwestern Greenland ice core, which is likely due to differences in the geological sources of the dust. Our results suggest that the EGRIP ice core dust was constantly supplied from Northern Eurasia, North America, and Asia with minor contribution from Greenland coast.
Sara E. Darychuk, Joseph M. Shea, Brian Menounos, Anna Chesnokova, Georg Jost, and Frank Weber
The Cryosphere, 17, 1457–1473, https://doi.org/10.5194/tc-17-1457-2023, https://doi.org/10.5194/tc-17-1457-2023, 2023
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We use synthetic-aperture radar (SAR) and optical observations to map snowmelt timing and duration on the watershed scale. We found that Sentinel-1 SAR time series can be used to approximate snowmelt onset over diverse terrain and land cover types, and we present a low-cost workflow for SAR processing over large, mountainous regions. Our approach provides spatially distributed observations of the snowpack necessary for model calibration and can be used to monitor snowmelt in ungauged basins.
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, https://doi.org/10.5194/nhess-22-3041-2022, https://doi.org/10.5194/nhess-22-3041-2022, 2022
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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.
Yota Sato, Koji Fujita, Hiroshi Inoue, Akiko Sakai, and Karma
The Cryosphere, 16, 2643–2654, https://doi.org/10.5194/tc-16-2643-2022, https://doi.org/10.5194/tc-16-2643-2022, 2022
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We investigate fluctuations in Bhutanese lake-terminating glaciers focusing on the dynamics change before and after proglacial lake formation at Thorthormi Glacier (TG) based on photogrammetry, satellite, and GPS surveys. The thinning rate of TG became double compared to before proglacial lake formation, and the flow velocity has also sped up considerably. Those changes would be due to the reduction in longitudinal ice compression by the detachment of the glacier terminus from the end moraine.
Stefan Fugger, Catriona L. Fyffe, Simone Fatichi, Evan Miles, Michael McCarthy, Thomas E. Shaw, Baohong Ding, Wei Yang, Patrick Wagnon, Walter Immerzeel, Qiao Liu, and Francesca Pellicciotti
The Cryosphere, 16, 1631–1652, https://doi.org/10.5194/tc-16-1631-2022, https://doi.org/10.5194/tc-16-1631-2022, 2022
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The monsoon is important for the shrinking and growing of glaciers in the Himalaya during summer. We calculate the melt of seven glaciers in the region using a complex glacier melt model and weather data. We find that monsoonal weather affects glaciers that are covered with a layer of rocky debris and glaciers without such a layer in different ways. It is important to take so-called turbulent fluxes into account. This knowledge is vital for predicting the future of the Himalayan glaciers.
Wouter J. Smolenaars, Sanita Dhaubanjar, Muhammad K. Jamil, Arthur Lutz, Walter Immerzeel, Fulco Ludwig, and Hester Biemans
Hydrol. Earth Syst. Sci., 26, 861–883, https://doi.org/10.5194/hess-26-861-2022, https://doi.org/10.5194/hess-26-861-2022, 2022
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The arid plains of the lower Indus Basin rely heavily on the water provided by the mountainous upper Indus. Rapid population growth in the upper Indus is expected to increase the water that is consumed there. This will subsequently reduce the water that is available for the downstream plains, where the population and water demand are also expected to grow. In future, this may aggravate tensions over the division of water between the countries that share the Indus Basin.
Naoko Nagatsuka, Kumiko Goto-Azuma, Akane Tsushima, Koji Fujita, Sumito Matoba, Yukihiko Onuma, Remi Dallmayr, Moe Kadota, Motohiro Hirabayashi, Jun Ogata, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Masahiro Minowa, Yuki Komuro, Hideaki Motoyama, and Teruo Aoki
Clim. Past, 17, 1341–1362, https://doi.org/10.5194/cp-17-1341-2021, https://doi.org/10.5194/cp-17-1341-2021, 2021
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Here we present a first high-temporal-resolution record of mineral composition in a Greenland ice core (SIGMA-D) over the past 100 years using SEM–EDS analysis. Our results show that the ice core dust composition varied on multi-decadal scales, which was likely affected by local temperature changes. We suggest that the ice core dust was constantly supplied from distant sources (mainly northern Canada) as well as local ice-free areas in warm periods (1915 to 1949 and 2005 to 2013).
Dhiraj Pradhananga, John W. Pomeroy, Caroline Aubry-Wake, D. Scott Munro, Joseph Shea, Michael N. Demuth, Nammy Hang Kirat, Brian Menounos, and Kriti Mukherjee
Earth Syst. Sci. Data, 13, 2875–2894, https://doi.org/10.5194/essd-13-2875-2021, https://doi.org/10.5194/essd-13-2875-2021, 2021
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This paper presents hydrological, meteorological, glaciological and geospatial data of Peyto Glacier Basin in the Canadian Rockies. They include high-resolution DEMs derived from air photos and lidar surveys and long-term hydrological and glaciological model forcing datasets derived from bias-corrected reanalysis products. These data are crucial for studying climate change and variability in the basin and understanding the hydrological responses of the basin to both glacier and climate change.
Maurice van Tiggelen, Paul C. J. P. Smeets, Carleen H. Reijmer, Bert Wouters, Jakob F. Steiner, Emile J. Nieuwstraten, Walter W. Immerzeel, and Michiel R. van den Broeke
The Cryosphere, 15, 2601–2621, https://doi.org/10.5194/tc-15-2601-2021, https://doi.org/10.5194/tc-15-2601-2021, 2021
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We developed a method to estimate the aerodynamic properties of the Greenland Ice Sheet surface using either UAV or ICESat-2 elevation data. We show that this new method is able to reproduce the important spatiotemporal variability in surface aerodynamic roughness, measured by the field observations. The new maps of surface roughness can be used in atmospheric models to improve simulations of surface turbulent heat fluxes and therefore surface energy and mass balance over rough ice worldwide.
Vincent Vionnet, Christopher B. Marsh, Brian Menounos, Simon Gascoin, Nicholas E. Wayand, Joseph Shea, Kriti Mukherjee, and John W. Pomeroy
The Cryosphere, 15, 743–769, https://doi.org/10.5194/tc-15-743-2021, https://doi.org/10.5194/tc-15-743-2021, 2021
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Mountain snow cover provides critical supplies of fresh water to downstream users. Its accurate prediction requires inclusion of often-ignored processes. A multi-scale modelling strategy is presented that efficiently accounts for snow redistribution. Model accuracy is assessed via airborne lidar and optical satellite imagery. With redistribution the model captures the elevation–snow depth relation. Redistribution processes are required to reproduce spatial variability, such as around ridges.
Xavier Fettweis, Stefan Hofer, Uta Krebs-Kanzow, Charles Amory, Teruo Aoki, Constantijn J. Berends, Andreas Born, Jason E. Box, Alison Delhasse, Koji Fujita, Paul Gierz, Heiko Goelzer, Edward Hanna, Akihiro Hashimoto, Philippe Huybrechts, Marie-Luise Kapsch, Michalea D. King, Christoph Kittel, Charlotte Lang, Peter L. Langen, Jan T. M. Lenaerts, Glen E. Liston, Gerrit Lohmann, Sebastian H. Mernild, Uwe Mikolajewicz, Kameswarrao Modali, Ruth H. Mottram, Masashi Niwano, Brice Noël, Jonathan C. Ryan, Amy Smith, Jan Streffing, Marco Tedesco, Willem Jan van de Berg, Michiel van den Broeke, Roderik S. W. van de Wal, Leo van Kampenhout, David Wilton, Bert Wouters, Florian Ziemen, and Tobias Zolles
The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020, https://doi.org/10.5194/tc-14-3935-2020, 2020
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We evaluated simulated Greenland Ice Sheet surface mass balance from 5 kinds of models. While the most complex (but expensive to compute) models remain the best, the faster/simpler models also compare reliably with observations and have biases of the same order as the regional models. Discrepancies in the trend over 2000–2012, however, suggest that large uncertainties remain in the modelled future SMB changes as they are highly impacted by the meltwater runoff biases over the current climate.
Remco J. de Kok, Philip D. A. Kraaijenbrink, Obbe A. Tuinenburg, Pleun N. J. Bonekamp, and Walter W. Immerzeel
The Cryosphere, 14, 3215–3234, https://doi.org/10.5194/tc-14-3215-2020, https://doi.org/10.5194/tc-14-3215-2020, 2020
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Glaciers worldwide are shrinking, yet glaciers in parts of High Mountain Asia are growing. Using models of the regional climate and glacier growth, we reproduce the observed patterns of glacier growth and shrinkage in High Mountain Asia of the last decades. Increases in snow, in part from water that comes from lowland agriculture, have probably been more important than changes in temperature to explain the growing glaciers. We now better understand changes in the crucial mountain water cycle.
Pleun N. J. Bonekamp, Chiel C. van Heerwaarden, Jakob F. Steiner, and Walter W. Immerzeel
The Cryosphere, 14, 1611–1632, https://doi.org/10.5194/tc-14-1611-2020, https://doi.org/10.5194/tc-14-1611-2020, 2020
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Drivers controlling melt of debris-covered glaciers are largely unknown. With a 3D turbulence-resolving model the impact of surface properties of debris on micrometeorological variables and the conductive heat flux is shown. Also, we show ice cliffs are local melt hot spots and that turbulent fluxes and local heat advection amplify spatial heterogeneity on the surface.This work is important for glacier mass balance modelling and for the understanding of the evolution of debris-covered glaciers.
Adrien Gilbert, Anna Sinisalo, Tika R. Gurung, Koji Fujita, Sudan B. Maharjan, Tenzing C. Sherpa, and Takehiro Fukuda
The Cryosphere, 14, 1273–1288, https://doi.org/10.5194/tc-14-1273-2020, https://doi.org/10.5194/tc-14-1273-2020, 2020
Naoki Sakurai, Chiyuki Narama, Mirlan Daiyrov, Muhammed Esenamanov, Zarylbek Usekov, and Hiroshi Inoue
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-62, https://doi.org/10.5194/tc-2020-62, 2020
Revised manuscript not accepted
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To better understand the storage in and drainage through supraglacial lakes and englacial conduits, we investigated the daily water-level variations of supraglacial lakes on the southern Inylchek Glacier in 2017, 2018, and 2019, using daily aerial digital images in 2017–2019 from an unmanned aerial vehicle (UAV). We observed the simultaneous drainage of five lakes, and argued that each lake must have been connected to the same main englacial conduit via a branch englacial conduit.
Markus M. Frey, Sarah J. Norris, Ian M. Brooks, Philip S. Anderson, Kouichi Nishimura, Xin Yang, Anna E. Jones, Michelle G. Nerentorp Mastromonaco, David H. Jones, and Eric W. Wolff
Atmos. Chem. Phys., 20, 2549–2578, https://doi.org/10.5194/acp-20-2549-2020, https://doi.org/10.5194/acp-20-2549-2020, 2020
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A winter sea ice expedition to Antarctica provided the first direct observations of sea salt aerosol (SSA) production during snow storms above sea ice, thereby validating a model hypothesis to account for winter time SSA maxima in Antarctica not explained otherwise. Defining SSA sources is important given the critical roles that aerosol plays for climate, for air quality and as a potential ice core proxy for sea ice conditions in the past.
S. Sapkota, N. R. Bhatt, D. P. Bhatt, A. Bist, S. Thapa, and R. B. Kayastha
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-5-W2, 83–88, https://doi.org/10.5194/isprs-annals-IV-5-W2-83-2019, https://doi.org/10.5194/isprs-annals-IV-5-W2-83-2019, 2019
Cristina Pérez-Guillén, Kae Tsunematsu, Kouichi Nishimura, and Dieter Issler
Earth Surf. Dynam., 7, 989–1007, https://doi.org/10.5194/esurf-7-989-2019, https://doi.org/10.5194/esurf-7-989-2019, 2019
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Avalanches and slush flows from Mt. Fuji are a major natural hazard as they may attain run-out distances of up to 4 km and destroy parts of the forest and infrastructure. We located and tracked them for the first time using seismic data. Numerical simulations were conducted to assess the precision of the seismic tracking. We also inferred dynamical properties characterizing these hazardous mass movements. This information is indispensable for assessing avalanche risk in the Mt. Fuji region.
Shun Tsutaki, Koji Fujita, Takayuki Nuimura, Akiko Sakai, Shin Sugiyama, Jiro Komori, and Phuntsho Tshering
The Cryosphere, 13, 2733–2750, https://doi.org/10.5194/tc-13-2733-2019, https://doi.org/10.5194/tc-13-2733-2019, 2019
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We investigate thickness change of Bhutanese glaciers during 2004–2011 using repeat GPS surveys and satellite-based observations. The thinning rate of Lugge Glacier (LG) is > 3 times that of Thorthormi Glacier (TG). Numerical simulations of ice dynamics and surface mass balance (SMB) demonstrate that the rapid thinning of LG is driven by both negative SMB and dynamic thinning, while the thinning of TG is minimised by a longitudinally compressive flow regime.
Satoru Yamaguchi, Masaaki Ishizaka, Hiroki Motoyoshi, Sent Nakai, Vincent Vionnet, Teruo Aoki, Katsuya Yamashita, Akihiro Hashimoto, and Akihiro Hachikubo
The Cryosphere, 13, 2713–2732, https://doi.org/10.5194/tc-13-2713-2019, https://doi.org/10.5194/tc-13-2713-2019, 2019
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The specific surface area (SSA) of solid precipitation particles (PPs) includes detailed information of PP. This work is based on field measurement of SSA of PPs in Nagaoka, the city with the heaviest snowfall in Japan. The values of SSA strongly depend on wind speed (WS) and wet-bulb temperature (Tw) on the ground. An equation to empirically estimate the SSA of fresh PPs with WS and Tw was established and the equation successfully reproduced the fluctuation of SSA in Nagaoka.
Koji Fujita, Sumito Matoba, Yoshinori Iizuka, Nozomu Takeuchi, and Teruo Aoki
Clim. Past Discuss., https://doi.org/10.5194/cp-2019-97, https://doi.org/10.5194/cp-2019-97, 2019
Revised manuscript not accepted
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This study presents a novel method for reconstructing summer temperatures from ice-layer thickness and annual accumulation in an ice core using an energy balance model. The method calculates a lookup table by considering heat conduction and meltwater refreezing in firn. We applied the method to four ice cores in different climates. Sensitivity analyses reveal that the annual temperature range, amount of annual precipitation, and firn albedo significantly affect the estimated summer temperature.
Akiko Sakai
The Cryosphere, 13, 2043–2049, https://doi.org/10.5194/tc-13-2043-2019, https://doi.org/10.5194/tc-13-2043-2019, 2019
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The Glacier Area Mapping for Discharge from the Asian Mountains (GAMDAM) glacier inventory was updated to revise the underestimated glacier area in the first version. The total number and area of glaciers are 134 770 and 100 693 ± 11 790 km2 from 453 Landsat images, which were carefully selected for the period from 1990 to 2010, to avoid mountain shadow, cloud cover, and seasonal snow cover.
Xin Yang, Markus M. Frey, Rachael H. Rhodes, Sarah J. Norris, Ian M. Brooks, Philip S. Anderson, Kouichi Nishimura, Anna E. Jones, and Eric W. Wolff
Atmos. Chem. Phys., 19, 8407–8424, https://doi.org/10.5194/acp-19-8407-2019, https://doi.org/10.5194/acp-19-8407-2019, 2019
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This is a comprehensive model–data comparison aiming to evaluate the proposed mechanism of sea salt aerosol (SSA) production from blowing snow on sea ice. Some key parameters such as snow salinity and blowing-snow size distribution were constrained by data collected in the Weddell Sea. The good agreement between modelled SSA and the cruise data strongly indicates that sea ice surface is a large SSA source in polar regions, a process which has not been considered in current climate models.
Teun van Woerkom, Jakob F. Steiner, Philip D. A. Kraaijenbrink, Evan S. Miles, and Walter W. Immerzeel
Earth Surf. Dynam., 7, 411–427, https://doi.org/10.5194/esurf-7-411-2019, https://doi.org/10.5194/esurf-7-411-2019, 2019
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Using data obtained from multiple UAV flights over a debris-covered glacier in the Himalaya between 2013 and 2018, we show that the adjacent moraines erode at rates of up to 16 cm per year, contributing to this debris cover. With retreating ice and resulting instability of moraines, this causes the glacier to cover a narrow zone along the lateral moraines in ever-thicker layers of rocks, resulting in a possible future decrease of local melt.
Sauvik Santra, Shubha Verma, Koji Fujita, Indrajit Chakraborty, Olivier Boucher, Toshihiko Takemura, John F. Burkhart, Felix Matt, and Mukesh Sharma
Atmos. Chem. Phys., 19, 2441–2460, https://doi.org/10.5194/acp-19-2441-2019, https://doi.org/10.5194/acp-19-2441-2019, 2019
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The present study provided information on specific glaciers over the Hindu Kush Himalayan region identified as being vulnerable to BC-induced impacts (affected by high BC-induced snow albedo reduction in addition to being sensitive to BC-induced impacts), thus impacting the downstream hydrology. The source-specific contribution to atmospheric BC aerosols by emission sources led to identifying the potential emission source, which was distinctive over south and north to 30° N.
Gilbert Guyomarc'h, Hervé Bellot, Vincent Vionnet, Florence Naaim-Bouvet, Yannick Déliot, Firmin Fontaine, Philippe Puglièse, Kouichi Nishimura, Yves Durand, and Mohamed Naaim
Earth Syst. Sci. Data, 11, 57–69, https://doi.org/10.5194/essd-11-57-2019, https://doi.org/10.5194/essd-11-57-2019, 2019
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The paper introduces a meteorological and blowing snow data set from Col du Lac Blanc (2720 m a.s.l., French Alps) allowing physical parameterizations and numerical models of blowing snow to be developed and evaluated. In situ winter season data consist of wind, snow depth, air temperature measurements and a database of blowing snow occurrence (2000–2016) complemented by measurements of blowing snow fluxes (2010–2016). Atmospheric data from a meteorological reanalysis and a DEM are also provided.
René Reijer Wijngaard, Hester Biemans, Arthur Friedrich Lutz, Arun Bhakta Shrestha, Philippus Wester, and Walter Willem Immerzeel
Hydrol. Earth Syst. Sci., 22, 6297–6321, https://doi.org/10.5194/hess-22-6297-2018, https://doi.org/10.5194/hess-22-6297-2018, 2018
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This study assesses the combined impacts of climate change and socio-economic developments on the future water gap for the Indus, Ganges, and Brahmaputra river basins until the end of the 21st century. The results show that despite projected increases in surface water availability, the strong socio-economic development and associated increase in water demand will likely lead to an increase in the water gap, indicating that socio-economic changes will be the key driver in the evolving water gap.
Simone Brunamonti, Teresa Jorge, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, K. Ravi Kumar, Sunil Sonbawne, Susanne Meier, Deepak Singh, Frank G. Wienhold, Bei Ping Luo, Maxi Boettcher, Yann Poltera, Hannu Jauhiainen, Rijan Kayastha, Jagadishwor Karmacharya, Ruud Dirksen, Manish Naja, Markus Rex, Suvarna Fadnavis, and Thomas Peter
Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, https://doi.org/10.5194/acp-18-15937-2018, 2018
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Based on balloon-borne measurements performed in India and Nepal in 2016–2017, we infer the vertical distributions of water vapor, ozone and aerosols in the atmosphere, from the surface to 30 km altitude. Our measurements show that the atmospheric dynamics of the Asian summer monsoon system over the polluted Indian subcontinent lead to increased concentrations of water vapor and aerosols in the high atmosphere (approximately 14–20 km altitude), which can have an important effect on climate.
Fanny Brun, Patrick Wagnon, Etienne Berthier, Joseph M. Shea, Walter W. Immerzeel, Philip D. A. Kraaijenbrink, Christian Vincent, Camille Reverchon, Dibas Shrestha, and Yves Arnaud
The Cryosphere, 12, 3439–3457, https://doi.org/10.5194/tc-12-3439-2018, https://doi.org/10.5194/tc-12-3439-2018, 2018
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On debris-covered glaciers, steep ice cliffs experience dramatically enhanced melt compared with the surrounding debris-covered ice. Using field measurements, UAV data and submetre satellite imagery, we estimate the cliff contribution to 2 years of ablation on a debris-covered tongue in Nepal, carefully taking into account ice dynamics. While they occupy only 7 to 8 % of the tongue surface, ice cliffs contributed to 23 to 24 % of the total tongue ablation.
Masashi Niwano, Teruo Aoki, Akihiro Hashimoto, Sumito Matoba, Satoru Yamaguchi, Tomonori Tanikawa, Koji Fujita, Akane Tsushima, Yoshinori Iizuka, Rigen Shimada, and Masahiro Hori
The Cryosphere, 12, 635–655, https://doi.org/10.5194/tc-12-635-2018, https://doi.org/10.5194/tc-12-635-2018, 2018
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We present a high-resolution regional climate model called NHM–SMAP applied to the Greenland Ice Sheet (GrIS). The model forced by JRA-55 reanalysis is evaluated using in situ data from automated weather stations, stake measurements,
and ice core obtained from 2011 to 2014. By utilizing the model, we highlight that the choice of calculation schemes for vertical water movement in snow and firn has an effect of up to 200 Gt/year in the yearly accumulated GrIS-wide surface mass balance estimates.
Jakob F. Steiner, Philip D. A. Kraaijenbrink, Sergiu G. Jiduc, and Walter W. Immerzeel
The Cryosphere, 12, 95–101, https://doi.org/10.5194/tc-12-95-2018, https://doi.org/10.5194/tc-12-95-2018, 2018
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Glaciers that once every few years or decades suddenly advance in length – also known as surging glaciers – are found in many glaciated regions in the world. In the Karakoram glacier tongues are additionally located at low altitudes and relatively close to human settlements. We investigate a very recent and extremely rapid surge in the region that has caused a lake to form in the main valley with possible risks for downstream communities.
Valentina Radić, Brian Menounos, Joseph Shea, Noel Fitzpatrick, Mekdes A. Tessema, and Stephen J. Déry
The Cryosphere, 11, 2897–2918, https://doi.org/10.5194/tc-11-2897-2017, https://doi.org/10.5194/tc-11-2897-2017, 2017
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Our overall goal is to improve the numerical modeling of glacier melt in order to better predict the future of glaciers in Western Canada and worldwide.
Most commonly used models rely on simplifications of processes that dictate melting at a glacier surface, in particular turbulent processes of heat exchange. We compared modeled against directly measured turbulent heat fluxes at a valley glacier in British Columbia, Canada, and found that more improvements are needed in all the tested models.
Damodar Lamsal, Koji Fujita, and Akiko Sakai
The Cryosphere, 11, 2815–2827, https://doi.org/10.5194/tc-11-2815-2017, https://doi.org/10.5194/tc-11-2815-2017, 2017
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This study presents the geodetic mass balance of Kanchenjunga Glacier, a heavily debris-covered glacier in the easternmost Nepal Himalaya, between 1975 and 2010 using high-resolution DEMs. The rate of elevation change positively correlates with elevation and glacier velocity, and significant surface lowering is observed at supraglacial ponds. A difference in pond density would strongly affect the different geodetic mass balances of the Kanchenjunga and Khumbu glaciers.
Hiroyuki Hirashima, Francesco Avanzi, and Satoru Yamaguchi
Hydrol. Earth Syst. Sci., 21, 5503–5515, https://doi.org/10.5194/hess-21-5503-2017, https://doi.org/10.5194/hess-21-5503-2017, 2017
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We reproduced the formation of capillary barriers and the development of preferential flow through snow using a multi-dimensional water transport model, which was then validated using laboratory experiments of liquid water infiltration into layered, initially dry snow. Simulation results showed that the model reconstructs some relevant features of capillary barriers and the timing of liquid water arrival at the snow base.
S. H. Ali, I. Bano, R. B. Kayastha, and A. Shrestha
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-2-W7, 1487–1494, https://doi.org/10.5194/isprs-archives-XLII-2-W7-1487-2017, https://doi.org/10.5194/isprs-archives-XLII-2-W7-1487-2017, 2017
Emmy E. Stigter, Niko Wanders, Tuomo M. Saloranta, Joseph M. Shea, Marc F. P. Bierkens, and Walter W. Immerzeel
The Cryosphere, 11, 1647–1664, https://doi.org/10.5194/tc-11-1647-2017, https://doi.org/10.5194/tc-11-1647-2017, 2017
Tobias Bolch, Tino Pieczonka, Kriti Mukherjee, and Joseph Shea
The Cryosphere, 11, 531–539, https://doi.org/10.5194/tc-11-531-2017, https://doi.org/10.5194/tc-11-531-2017, 2017
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Previous geodetic estimates of glacier mass changes in the Karakoram have revealed balanced budgets or a possible slight mass gain since the year ∼ 2000. We used old US reconnaissance imagery and could show that glaciers in the Hunza River basin (Central Karakoram) experienced on average no significant mass changes also since the 1970s. Likewise the glaciers had heterogeneous behaviour with frequent surge activities during the last 40 years.
Walter Immerzeel, Philip Kraaijenbrink, and Liss Andreassen
The Cryosphere Discuss., https://doi.org/10.5194/tc-2016-292, https://doi.org/10.5194/tc-2016-292, 2017
Revised manuscript not accepted
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Unmanned Aerial Vehicles (UAV) have become increasingly popular in environmental monitoring. In this study we use a UAV to derive a very detailed digital elevation model (DEM) of Storbreen in Norway. We compare our results with a past DEM to derive the mass balance of this glacier. Our results confirm strong mass loss and retreat of continental glaciers in southern Norway and we conclude that UAVs are effective tools in stuyding mountain glaciers at a high level of detail.
Masaaki Ishizaka, Hiroki Motoyoshi, Satoru Yamaguchi, Sento Nakai, Toru Shiina, and Ken-ichiro Muramoto
The Cryosphere, 10, 2831–2845, https://doi.org/10.5194/tc-10-2831-2016, https://doi.org/10.5194/tc-10-2831-2016, 2016
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We measured the snowfall densities with a CCD camera, simultaneously observing the predominant snowfall types determined by the measured size and the fall speed. With a CCD camera, we obtain the quantitative relationships between snowfall densities and presumed density derived from the size and mass components. This suggests the possibility of estimating snowfall densities from the measured size and the fall speed data, and using them as the initial densities for a snowpack in a numerical model.
Francesco Avanzi, Hiroyuki Hirashima, Satoru Yamaguchi, Takafumi Katsushima, and Carlo De Michele
The Cryosphere, 10, 2013–2026, https://doi.org/10.5194/tc-10-2013-2016, https://doi.org/10.5194/tc-10-2013-2016, 2016
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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.
Christian Vincent, Patrick Wagnon, Joseph M. Shea, Walter W. Immerzeel, Philip Kraaijenbrink, Dibas Shrestha, Alvaro Soruco, Yves Arnaud, Fanny Brun, Etienne Berthier, and Sonam Futi Sherpa
The Cryosphere, 10, 1845–1858, https://doi.org/10.5194/tc-10-1845-2016, https://doi.org/10.5194/tc-10-1845-2016, 2016
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Approximately 25 % of the glacierized area in the Everest region is covered by debris, yet the surface mass balance of these glaciers has not been measured directly. From terrestrial photogrammetry and unmanned aerial vehicle (UAV) methods, this study shows that the ablation is strongly reduced by the debris cover. The insulating effect of the debris cover has a larger effect on total mass loss than the enhanced ice ablation due to supraglacial ponds and exposed ice cliffs.
Anna Dittmann, Elisabeth Schlosser, Valérie Masson-Delmotte, Jordan G. Powers, Kevin W. Manning, Martin Werner, and Koji Fujita
Atmos. Chem. Phys., 16, 6883–6900, https://doi.org/10.5194/acp-16-6883-2016, https://doi.org/10.5194/acp-16-6883-2016, 2016
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For a better understanding of the stable water isotope data from ice cores, recent time periods have to be analysed, where both measurements and model simulations are available. This was done for Dome Fuji by combining observations, synoptic analysis, back trajectories, and isotopic modelling. It was found that a more northerly moisture source does not necessarily mean a larger temperature difference between source area and deposition site and thus precipitation more depleted in heavy isotopes.
H. Nagai, K. Fujita, A. Sakai, T. Nuimura, and T. Tadono
The Cryosphere, 10, 65–85, https://doi.org/10.5194/tc-10-65-2016, https://doi.org/10.5194/tc-10-65-2016, 2016
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Digital glacier inventories are invaluable data sets for revealing the characteristics of glacier distribution. However, quantitative comparison of present inventories was not performed. Here, we present a new inventory manually delineated from Advanced Land Observing Satellite (ALOS) imagery and compare it with existing inventories for the Bhutan Himalaya. Quantification of overlapping among available glacier outlines suggests consistency and recent improvement of their delineation quality.
W. W. Immerzeel, N. Wanders, A. F. Lutz, J. M. Shea, and M. F. P. Bierkens
Hydrol. Earth Syst. Sci., 19, 4673–4687, https://doi.org/10.5194/hess-19-4673-2015, https://doi.org/10.5194/hess-19-4673-2015, 2015
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The water resources of the upper Indus river basin (UIB) are important for millions of people, yet little is known about the rain and snow fall in the high-altitude regions because of the inaccessibility, the climatic complexity and the lack of observations. In this study we use mass balance of glaciers to reconstruct the amount of precipitation in the UIB and we conclude that this amount is much higher than previously thought.
S. Miyazaki, K. Saito, J. Mori, T. Yamazaki, T. Ise, H. Arakida, T. Hajima, Y. Iijima, H. Machiya, T. Sueyoshi, H. Yabuki, E. J. Burke, M. Hosaka, K. Ichii, H. Ikawa, A. Ito, A. Kotani, Y. Matsuura, M. Niwano, T. Nitta, R. O'ishi, T. Ohta, H. Park, T. Sasai, A. Sato, H. Sato, A. Sugimoto, R. Suzuki, K. Tanaka, S. Yamaguchi, and K. Yoshimura
Geosci. Model Dev., 8, 2841–2856, https://doi.org/10.5194/gmd-8-2841-2015, https://doi.org/10.5194/gmd-8-2841-2015, 2015
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The paper provides an overall outlook and the Stage 1 experiment (site simulations) protocol of GTMIP, an open model intercomparison project for terrestrial Arctic, conducted as an activity of the Japan-funded Arctic Climate Change Research Project (GRENE-TEA). Models are driven by 34-year data created with the GRENE-TEA observations at four sites in Finland, Siberia and Alaska, and evaluated for physico-ecological key processes: energy budgets, snow, permafrost, phenology, and carbon budget.
E. Collier, F. Maussion, L. I. Nicholson, T. Mölg, W. W. Immerzeel, and A. B. G. Bush
The Cryosphere, 9, 1617–1632, https://doi.org/10.5194/tc-9-1617-2015, https://doi.org/10.5194/tc-9-1617-2015, 2015
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We investigate the impact of surface debris on glacier energy and mass fluxes and on atmosphere-glacier feedbacks in the Karakoram range, by including debris in an interactively coupled atmosphere-glacier model. The model is run from 1 May to 1 October 2004, with a simple specification of debris thickness. We find an appreciable reduction in ablation that exceeds 5m w.e. on glacier tongues, as well as significant alterations to near-surface air temperatures and boundary layer dynamics.
W. Terink, A. F. Lutz, G. W. H. Simons, W. W. Immerzeel, and P. Droogers
Geosci. Model Dev., 8, 2009–2034, https://doi.org/10.5194/gmd-8-2009-2015, https://doi.org/10.5194/gmd-8-2009-2015, 2015
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This paper introduces the Spatial Processes in HYdrology (SPHY) model (v2.0), its underlying concepts, and some example applications. SPHY has the flexibility to be applied in a wide range of hydrologic applications, on various scales, and can easily be implemented. The most relevant hydrologic processes integrated in the SPHY model are rainfall--runoff, cryosphere processes, evapotranspiration processes, the dynamic evolution of evolution of vegetation cover, and lake/reservoir outflow.
J. M. Shea, W. W. Immerzeel, P. Wagnon, C. Vincent, and S. Bajracharya
The Cryosphere, 9, 1105–1128, https://doi.org/10.5194/tc-9-1105-2015, https://doi.org/10.5194/tc-9-1105-2015, 2015
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A glacier mass balance and redistribution model that integrates field observations and downscaled climate fields is developed to examine glacier sensitivity to future climate in the Everest region of Nepal. The modelled sensitivity of glaciers to future climate change is high, and glacier mass loss is sustained through the 21st century for both middle- and high-emission scenarios. Projected temperature increases will expose large glacier areas to melt and reduce snow accumulations.
M. Niwano, T. Aoki, S. Matoba, S. Yamaguchi, T. Tanikawa, K. Kuchiki, and H. Motoyama
The Cryosphere, 9, 971–988, https://doi.org/10.5194/tc-9-971-2015, https://doi.org/10.5194/tc-9-971-2015, 2015
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A physical snowpack model SMAP and in situ meteorological and snow data obtained at site SIGMA-A on the northwest Greenland ice sheet are used to assess surface energy balance during the extreme near-surface snowmelt event around 12 July 2012. We determined that the main factor for the melt event observed at the SIGMA-A site was low-level clouds accompanied by a significant temperature increase, which induced surface heating via cloud radiative forcing in the polar region.
T. Nuimura, A. Sakai, K. Taniguchi, H. Nagai, D. Lamsal, S. Tsutaki, A. Kozawa, Y. Hoshina, S. Takenaka, S. Omiya, K. Tsunematsu, P. Tshering, and K. Fujita
The Cryosphere, 9, 849–864, https://doi.org/10.5194/tc-9-849-2015, https://doi.org/10.5194/tc-9-849-2015, 2015
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We present a new glacier inventory for high-mountain Asia named “Glacier Area Mapping for Discharge from the Asian Mountains” (GAMDAM). Glacier outlines were delineated manually using 356 Landsat ETM+ scenes in 226 path-row sets from the period 1999–2003, in conjunction with a digital elevation model and high-resolution Google EarthTM imagery. Our GAMDAM Glacier Inventory includes 87,084 glaciers covering a total area of 91,263 ± 13,689 km2 throughout high-mountain Asia.
A. Sakai, T. Nuimura, K. Fujita, S. Takenaka, H. Nagai, and D. Lamsal
The Cryosphere, 9, 865–880, https://doi.org/10.5194/tc-9-865-2015, https://doi.org/10.5194/tc-9-865-2015, 2015
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Among meteorological elements, precipitation has a large spatial variability and less observation, particularly in high-mountain Asia, although precipitation in mountains is an important parameter for hydrological circulation. Based on the GAMDAM glacier inventory, we estimated precipitation contributing to glacier mass at the median elevation of glaciers, which is presumed to be at equilibrium-line altitude, by tuning adjustment parameters of precipitation.
F. Brun, M. Dumont, P. Wagnon, E. Berthier, M. F. Azam, J. M. Shea, P. Sirguey, A. Rabatel, and Al. Ramanathan
The Cryosphere, 9, 341–355, https://doi.org/10.5194/tc-9-341-2015, https://doi.org/10.5194/tc-9-341-2015, 2015
K. Fujita and A. Sakai
Hydrol. Earth Syst. Sci., 18, 2679–2694, https://doi.org/10.5194/hess-18-2679-2014, https://doi.org/10.5194/hess-18-2679-2014, 2014
J. T. M. Lenaerts, C. J. P. P. Smeets, K. Nishimura, M. Eijkelboom, W. Boot, M. R. van den Broeke, and W. J. van de Berg
The Cryosphere, 8, 801–814, https://doi.org/10.5194/tc-8-801-2014, https://doi.org/10.5194/tc-8-801-2014, 2014
P. Wagnon, C. Vincent, Y. Arnaud, E. Berthier, E. Vuillermoz, S. Gruber, M. Ménégoz, A. Gilbert, M. Dumont, J. M. Shea, D. Stumm, and B. K. Pokhrel
The Cryosphere, 7, 1769–1786, https://doi.org/10.5194/tc-7-1769-2013, https://doi.org/10.5194/tc-7-1769-2013, 2013
H. Nagai, K. Fujita, T. Nuimura, and A. Sakai
The Cryosphere, 7, 1303–1314, https://doi.org/10.5194/tc-7-1303-2013, https://doi.org/10.5194/tc-7-1303-2013, 2013
K. Fujita, A. Sakai, S. Takenaka, T. Nuimura, A. B. Surazakov, T. Sawagaki, and T. Yamanokuchi
Nat. Hazards Earth Syst. Sci., 13, 1827–1839, https://doi.org/10.5194/nhess-13-1827-2013, https://doi.org/10.5194/nhess-13-1827-2013, 2013
Y. Zhang, Y. Hirabayashi, K. Fujita, S. Liu, and Q. Liu
The Cryosphere Discuss., https://doi.org/10.5194/tcd-7-2413-2013, https://doi.org/10.5194/tcd-7-2413-2013, 2013
Revised manuscript not accepted
Related subject area
Other Hazards (e.g., Glacial and Snow Hazards, Karst, Wildfires Hazards, and Medical Geo-Hazards)
Assessing the performance and explainability of an avalanche danger forecast model
Development of operational decision support tools for mechanized ski guiding using avalanche terrain modeling, GPS tracking, and machine learning
Causes, consequences and implications of the 2023 landslide-induced Lake Rasac glacial lake outburst flood (GLOF), Cordillera Huayhuash, Peru
The Avalanche Terrain Exposure Scale (ATES) v.2
Review article: A scoping review of human factors in avalanche decision-making
A quantitative module of avalanche hazard – comparing forecaster assessments of storm and persistent slab avalanche problems with information derived from distributed snowpack simulations
Modelling current and future forest fire susceptibility in north-eastern Germany
The effect of propagation saw test geometries on critical cut length
Statistical calibration of probabilistic medium-range Fire Weather Index forecasts in Europe
Seismic Signal Classification of Snow Avalanches using Distributed Acoustic Sensing in Grasdalen, Western Norway
Glide-snow avalanches: a mechanical, threshold-based release area model
Improving fire severity prediction in south-eastern Australia using vegetation-specific information
Proglacial lake evolution and outburst flood hazard at Fjallsjökull glacier, southeast Iceland
How hard do avalanche practitioners tap during snow stability tests?
A large-scale validation of snowpack simulations in support of avalanche forecasting focusing on critical layers
The effect of slab touchdown on anticrack arrest in propagation saw tests
A glacial lake outburst flood risk assessment for the Phochhu river basin, Bhutan
AutoATES v2.0: Automated Avalanche Terrain Exposure Scale mapping
Modelling the vulnerability of urban settings to wildland–urban interface fires in Chile
Modeling of indoor 222Rn in data-scarce regions: an interactive dashboard approach for Bogotá, Colombia
Simulation of cold powder avalanches considering daily snowpack and weather situations to enhance road safety
Supershear crack propagation in snow slab avalanche release: new insights from numerical simulations and field measurements
A regional early warning for slushflow hazard
A new approach for drought index adjustment to clay-shrinkage-induced subsidence over France: advantages of the interactive leaf area index
Automated Avalanche Terrain Exposure Scale (ATES) mapping – local validation and optimization in western Canada
An Efficient Method to Simulate Wildfire Propagation Using Irregular Grids
Improving the fire weather index system for peatlands using peat-specific hydrological input data
Brief communication: The Lahaina Fire disaster – how models can be used to understand and predict wildfires
Prediction of natural dry-snow avalanche activity using physics-based snowpack simulations
Early warning system for ice collapses and river blockages in the Sedongpu Valley, southeastern Tibetan Plateau
Fire risk modeling: an integrated and data-driven approach applied to Sicily
Avalanche size estimation and avalanche outline determination by experts: reliability and implications for practice
Fluid conduits and shallow-reservoir structure defined by geoelectrical tomography at the Nirano Salse (Italy)
Estimating the effects of meteorology and land cover on fire growth in Peru using a novel difference equation model
Review article: Snow and ice avalanches in high mountain Asia – scientific, local and indigenous knowledge
Reduced-order digital twin and latent data assimilation for global wildfire prediction
A user perspective on the avalanche danger scale – insights from North America
Characterizing the rate of spread of large wildfires in emerging fire environments of northwestern Europe using Visible Infrared Imaging Radiometer Suite active fire data
Evaluation of low-cost Raspberry Pi sensors for structure-from-motion reconstructions of glacier calving fronts
Temporal evolution of crack propagation characteristics in a weak snowpack layer: conditions of crack arrest and sustained propagation
A data-driven model for Fennoscandian wildfire danger
Equivalent hazard magnitude scale
Statistical modelling of air quality impacts from individual forest fires in New South Wales, Australia
Drivers of extreme burnt area in Portugal: fire weather and vegetation
Coupling wildfire spread simulations and connectivity analysis for hazard assessment: a case study in Serra da Cabreira, Portugal
Glacial lake outburst flood hazard under current and future conditions: worst-case scenarios in a transboundary Himalayan basin
What weather variables are important for wet and slab avalanches under a changing climate in a low-altitude mountain range in Czechia?
Modelling ignition probability for human- and lightning-caused wildfires in Victoria, Australia
Automated snow avalanche release area delineation in data-sparse, remote, and forested regions
The 2017 Split wildfire in Croatia: evolution and the role of meteorological conditions
Cristina Pérez-Guillén, Frank Techel, Michele Volpi, and Alec van Herwijnen
Nat. Hazards Earth Syst. Sci., 25, 1331–1351, https://doi.org/10.5194/nhess-25-1331-2025, https://doi.org/10.5194/nhess-25-1331-2025, 2025
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This study assesses the performance and explainability of a random-forest classifier for predicting dry-snow avalanche danger levels during initial live testing. The model achieved ∼ 70 % agreement with human forecasts, performing equally well in nowcast and forecast modes, while capturing the temporal dynamics of avalanche forecasting. The explainability approach enhances the transparency of the model's decision-making process, providing a valuable tool for operational avalanche forecasting.
John Sykes, Pascal Haegeli, Roger Atkins, Patrick Mair, and Yves Bühler
Nat. Hazards Earth Syst. Sci., 25, 1255–1292, https://doi.org/10.5194/nhess-25-1255-2025, https://doi.org/10.5194/nhess-25-1255-2025, 2025
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We model the decision-making of professional ski guides and develop decision support tools to assist with determining appropriate terrain based on current conditions. Our approach compares a manually constructed Bayesian network with machine learning classification models. The models accurately capture the real-world decision-making outcomes in 85–93 % of cases. Our conclusions focus on strengths and weaknesses of each model and discuss ramifications for practical applications in ski guiding.
Adam Emmer, Oscar Vilca, Cesar Salazar Checa, Sihan Li, Simon Cook, Elena Pummer, Jan Hrebrina, and Wilfried Haeberli
Nat. Hazards Earth Syst. Sci., 25, 1207–1228, https://doi.org/10.5194/nhess-25-1207-2025, https://doi.org/10.5194/nhess-25-1207-2025, 2025
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We describe in detail the most recent large landslide-triggered glacial lake outburst flood (GLOF) in the Peruvian Andes (the 2023 Rasac GLOF), analysing its preconditions and consequences, as well as the role of the changing climate. Our study contributes to understanding GLOF occurrence patterns in space and time and corroborates reports detailing the increasing frequency of such events in changing mountains.
Grant Statham and Cam Campbell
Nat. Hazards Earth Syst. Sci., 25, 1113–1137, https://doi.org/10.5194/nhess-25-1113-2025, https://doi.org/10.5194/nhess-25-1113-2025, 2025
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The Avalanche Terrain Exposure Scale (ATES) is an avalanche terrain rating system used for terrain assessment and risk communication in public and workplace avalanche safety practices. This paper introduces ATES v.2, an update that expands the original scale from three levels to five by including Class 0 – Non-avalanche terrain and Class 4 – Extreme terrain. The updated models for assessment and communication are described in detail, along with guidance for the application of ATES.
Audun Hetland, Rebecca A. Hetland, Tarjei Tveito Skille, and Andrea Mannberg
Nat. Hazards Earth Syst. Sci., 25, 929–948, https://doi.org/10.5194/nhess-25-929-2025, https://doi.org/10.5194/nhess-25-929-2025, 2025
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Research on human factors in avalanche decision-making has become increasingly popular in the past 2 decades. The studies span a wide range of disciplines and are published in a variety of journals. To provide an overview of this literature, this study provides a systematic scoping review of human factors in avalanche decision-making. A total of 70 papers fulfilled the search criteria. We extracted data and sorted the papers according to their main themes.
Florian Herla, Pascal Haegeli, Simon Horton, and Patrick Mair
Nat. Hazards Earth Syst. Sci., 25, 625–646, https://doi.org/10.5194/nhess-25-625-2025, https://doi.org/10.5194/nhess-25-625-2025, 2025
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We present a spatial framework for extracting information about avalanche problems from detailed snowpack simulations and compare the numerical results against operational assessments from avalanche forecasters. Despite good agreement in seasonal summary statistics, a comparison of daily assessments revealed considerable differences, while it remained unclear which data source represented reality the best. We discuss how snowpack simulations can add value to the forecasting process.
Katharina H. Horn, Stenka Vulova, Hanyu Li, and Birgit Kleinschmit
Nat. Hazards Earth Syst. Sci., 25, 383–401, https://doi.org/10.5194/nhess-25-383-2025, https://doi.org/10.5194/nhess-25-383-2025, 2025
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In this study we applied a random forest machine learning algorithm to model current and future forest fire susceptibility (FFS) in north-eastern Germany using anthropogenic, climatic, topographic, soil, and vegetation variables. Model accuracy ranged between 69 % and 71 %, showing moderately high model reliability for predicting FFS. The model results underline the importance of anthropogenic and vegetation parameters. This study will support regional forest fire prevention and management.
Bastian Bergfeld, Karl W. Birkeland, Valentin Adam, Philipp L. Rosendahl, and Alec van Herwijnen
Nat. Hazards Earth Syst. Sci., 25, 321–334, https://doi.org/10.5194/nhess-25-321-2025, https://doi.org/10.5194/nhess-25-321-2025, 2025
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To release a slab avalanche, a crack in a weak snow layer beneath a cohesive slab has to propagate. Information on that is essential for assessing avalanche risk. In the field, information can be gathered with the propagation saw test (PST). However, there are different standards on how to cut the PST. In this study, we experimentally investigate the effect of these different column geometries and provide models to correct for imprecise field test geometry effects on the critical cut length.
Stephanie Bohlmann and Marko Laine
Nat. Hazards Earth Syst. Sci., 24, 4225–4235, https://doi.org/10.5194/nhess-24-4225-2024, https://doi.org/10.5194/nhess-24-4225-2024, 2024
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Probabilistic ensemble forecasts of the Canadian Forest Fire Weather Index (FWI) can be used to estimate the possible wildfire risk but require post-processing to provide accurate and reliable predictions. This article presents a calibration method using non-homogeneous Gaussian regression to statistically post-process FWI forecasts up to 15 d. Calibration improves the forecast especially at short lead times and in regions with high fire risk.
Franz Kleine, Charlotte Bruland, Andreas Wüstefeld, Volker Oye, and Martin Landrø
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-202, https://doi.org/10.5194/nhess-2024-202, 2024
Revised manuscript accepted for NHESS
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We used a fiber optic cable along a road in western Norway to study snow avalanches signals. Our study shows that avalanches create distinct signals in the 20–50 Hz frequency range, with larger ones having weak early warning signals. However, road traffic interference complicates automatic detection. This research highlights the potential of using existing infrastructure for avalanche monitoring. Further improvements are needed for automated detection.
Amelie Fees, Alec van Herwijnen, Michael Lombardo, Jürg Schweizer, and Peter Lehmann
Nat. Hazards Earth Syst. Sci., 24, 3387–3400, https://doi.org/10.5194/nhess-24-3387-2024, https://doi.org/10.5194/nhess-24-3387-2024, 2024
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Glide-snow avalanches release at the ground–snow interface, and their release process is poorly understood. To investigate the influence of spatial variability (snowpack and basal friction) on avalanche release, we developed a 3D, mechanical, threshold-based model that reproduces an observed release area distribution. A sensitivity analysis showed that the distribution was mostly influenced by the basal friction uniformity, while the variations in snowpack properties had little influence.
Kang He, Xinyi Shen, Cory Merow, Efthymios Nikolopoulos, Rachael V. Gallagher, Feifei Yang, and Emmanouil N. Anagnostou
Nat. Hazards Earth Syst. Sci., 24, 3337–3355, https://doi.org/10.5194/nhess-24-3337-2024, https://doi.org/10.5194/nhess-24-3337-2024, 2024
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A framework combining a fire severity classification with a regression model to predict an indicator of fire severity derived from Landsat imagery (difference normalized burning ratio, dNBR) is proposed. The results show that the proposed predictive technique is capable of providing robust fire severity prediction information, which can be used for forecasting seasonal fire severity and, subsequently, impacts on biodiversity and ecosystems under projected future climate conditions.
Greta Hoe Wells, Þorsteinn Sæmundsson, Finnur Pálsson, Guðfinna Aðalgeirsdóttir, Eyjólfur Magnússon, Reginald L. Hermanns, and Snævarr Guðmundsson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2002, https://doi.org/10.5194/egusphere-2024-2002, 2024
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Glacier retreat elevates the risk of landslides released into proglacial lakes, which can trigger glacial lake outburst floods (GLOFs). This study maps proglacial lake evolution and GLOF hazard scenarios at Fjallsjökull glacier, Iceland. Lake volume increased from 1945–2021 and is estimated to triple over the next century. Three slopes are prone to landslides that may trigger GLOFs. Results will mitigate flood hazard at this popular tourism site and advance GLOF research in Iceland and globally.
Håvard B. Toft, Samuel V. Verplanck, and Markus Landrø
Nat. Hazards Earth Syst. Sci., 24, 2757–2772, https://doi.org/10.5194/nhess-24-2757-2024, https://doi.org/10.5194/nhess-24-2757-2024, 2024
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This study investigates inconsistencies in impact force as part of extended column tests (ECTs). We measured force-time curves from 286 practitioners in Scandinavia, Central Europe, and North America. The results show a large variability in peak forces and loading rates across wrist, elbow, and shoulder taps, challenging the ECT's reliability.
Florian Herla, Pascal Haegeli, Simon Horton, and Patrick Mair
Nat. Hazards Earth Syst. Sci., 24, 2727–2756, https://doi.org/10.5194/nhess-24-2727-2024, https://doi.org/10.5194/nhess-24-2727-2024, 2024
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Snowpack simulations are increasingly employed by avalanche warning services to inform about critical avalanche layers buried in the snowpack. However, validity concerns limit their operational value. We present methods that enable meaningful comparisons between snowpack simulations and regional assessments of avalanche forecasters to quantify the performance of the Canadian weather and snowpack model chain to represent thin critical avalanche layers on a large scale and in real time.
Philipp L. Rosendahl, Johannes Schneider, Grégoire Bobillier, Florian Rheinschmidt, Bastian Bergfeld, Alec van Herwijnen, and Philipp Weißgraeber
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-122, https://doi.org/10.5194/nhess-2024-122, 2024
Revised manuscript accepted for NHESS
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Our research investigates the role of anticracks in snowpacks and their impact on avalanche formation, focusing on anticracks due to weak layer collapse. We discovered that slab touchdown on the snow below the weak layer decreases the energy available for crack propagation, potentially leading to a stop of crack propagation. This underscores the importance of mechanical interactions in snowpack stability. Our work offers new insights for enhancing avalanche prediction and mitigation strategies.
Tandin Wangchuk and Ryota Tsubaki
Nat. Hazards Earth Syst. Sci., 24, 2523–2540, https://doi.org/10.5194/nhess-24-2523-2024, https://doi.org/10.5194/nhess-24-2523-2024, 2024
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A glacial lake outburst flood (GLOF) is a natural hazard in which water from a glacier-fed lake is swiftly discharged, causing serious harm to life, infrastructure, and communities. We used numerical models to predict the potential consequences of a GLOF originating from the Thorthomi glacial lake in Bhutan. We found that if a GLOF occurs, the lake could release massive flood water within 4 h, posing a considerable risk. Study findings help to mitigate the impacts of future GLOFs.
Håvard B. Toft, John Sykes, Andrew Schauer, Jordy Hendrikx, and Audun Hetland
Nat. Hazards Earth Syst. Sci., 24, 1779–1793, https://doi.org/10.5194/nhess-24-1779-2024, https://doi.org/10.5194/nhess-24-1779-2024, 2024
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Manual Avalanche Terrain Exposure Scale (ATES) mapping is time-consuming and inefficient for large-scale applications. The updated algorithm for automated ATES mapping overcomes previous limitations by including forest density data, improving the avalanche runout estimations in low-angle runout zones, accounting for overhead exposure and open-source software. Results show that the latest version has significantly improved its performance.
Paula Aguirre, Jorge León, Constanza González-Mathiesen, Randy Román, Manuela Penas, and Alonso Ogueda
Nat. Hazards Earth Syst. Sci., 24, 1521–1537, https://doi.org/10.5194/nhess-24-1521-2024, https://doi.org/10.5194/nhess-24-1521-2024, 2024
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Wildfires pose a significant risk to property located in the wildland–urban interface (WUI). To assess and mitigate this risk, we need to understand which characteristics of buildings and building arrangements make them more prone to damage. We used a combination of data collection and analysis methods to study the vulnerability of dwellings in the WUI for case studies in Chile and concluded that the spatial arrangement of houses has a substantial impact on their vulnerability to wildfires.
Martín Domínguez Durán, María Angélica Sandoval Garzón, and Carme Huguet
Nat. Hazards Earth Syst. Sci., 24, 1319–1339, https://doi.org/10.5194/nhess-24-1319-2024, https://doi.org/10.5194/nhess-24-1319-2024, 2024
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In this study we created a cost-effective alternative to bridge the baseline information gap on indoor radon (a highly carcinogenic gas) in regions where measurements are scarce. We model indoor radon concentrations to understand its spatial distribution and the potential influential factors. We evaluated the performance of this alternative using a small number of measurements taken in Bogotá, Colombia. Our results show that this alternative could help in the making of future studies and policy.
Julia Glaus, Katreen Wikstrom Jones, Perry Bartelt, Marc Christen, Lukas Stoffel, Johan Gaume, and Yves Bühler
EGUsphere, https://doi.org/10.5194/egusphere-2024-771, https://doi.org/10.5194/egusphere-2024-771, 2024
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This study assesses RAMMS::EXTENDED's predictive power in estimating avalanche run-out distances critical for mountain road safety. Leveraging meteorological data and sensitivity analysis, it offers meaningful predictions, aiding near real-time hazard assessments and future model refinement for improved decision-making.
Grégoire Bobillier, Bertil Trottet, Bastian Bergfeld, Ron Simenhois, Alec van Herwijnen, Jürg Schweizer, and Johan Gaume
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-70, https://doi.org/10.5194/nhess-2024-70, 2024
Revised manuscript accepted for NHESS
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Our study focuses on the initiation process of snow slab avalanches. By combining experimental data and numerical simulations, we show that on gentle slopes, a crack forms and propagates due to compression fracture within a weak layer, and on steep slopes, the crack velocity can increase dramatically after about 5 meters due to a fracture mode transition (compression to shear). Understanding these dynamics represents an essential additional piece in the dry-snow slab avalanche formation puzzle.
Monica Sund, Heidi A. Grønsten, and Siv Å. Seljesæter
Nat. Hazards Earth Syst. Sci., 24, 1185–1201, https://doi.org/10.5194/nhess-24-1185-2024, https://doi.org/10.5194/nhess-24-1185-2024, 2024
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Slushflows are rapid mass movements of water-saturated snow released in gently sloping terrain (< 30°), often unexpectedly. Early warning is crucial to prevent casualties and damage to infrastructure. A regional early warning for slushflow hazard was established in Norway in 2013–2014 and has been operational since. We present a methodology using the ratio between water supply and snow depth by snow type to assess slushflow hazard. This approach is useful for other areas with slushflow hazard.
Sophie Barthelemy, Bertrand Bonan, Jean-Christophe Calvet, Gilles Grandjean, David Moncoulon, Dorothée Kapsambelis, and Séverine Bernardie
Nat. Hazards Earth Syst. Sci., 24, 999–1016, https://doi.org/10.5194/nhess-24-999-2024, https://doi.org/10.5194/nhess-24-999-2024, 2024
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This work presents a drought index specifically adapted to subsidence, a seasonal phenomenon of soil shrinkage that occurs frequently in France and damages buildings. The index is computed from land surface model simulations and evaluated by a rank correlation test with insurance data. With its optimal configuration, the index is able to identify years of both zero and significant loss.
John Sykes, Håvard Toft, Pascal Haegeli, and Grant Statham
Nat. Hazards Earth Syst. Sci., 24, 947–971, https://doi.org/10.5194/nhess-24-947-2024, https://doi.org/10.5194/nhess-24-947-2024, 2024
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The research validates and optimizes an automated approach for creating classified snow avalanche terrain maps using open-source geospatial modeling tools. Validation is based on avalanche-expert-based maps for two study areas. Our results show that automated maps have an overall accuracy equivalent to the average accuracy of three human maps. Automated mapping requires a fraction of the time and cost of traditional methods and opens the door for large-scale mapping of mountainous terrain.
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, https://doi.org/10.5194/nhess-2024-27, 2024
Revised manuscript accepted for NHESS
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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.
Jonas Mortelmans, Anne Felsberg, Gabriëlle J. M. De Lannoy, Sander Veraverbeke, Robert D. Field, Niels Andela, and Michel Bechtold
Nat. Hazards Earth Syst. Sci., 24, 445–464, https://doi.org/10.5194/nhess-24-445-2024, https://doi.org/10.5194/nhess-24-445-2024, 2024
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With global warming increasing the frequency and intensity of wildfires in the boreal region, accurate risk assessments are becoming more crucial than ever before. The Canadian Fire Weather Index (FWI) is a renowned system, yet its effectiveness in peatlands, where hydrology plays a key role, is limited. By incorporating groundwater data from numerical models and satellite observations, our modified FWI improves the accuracy of fire danger predictions, especially over summer.
Timothy W. Juliano, Fernando Szasdi-Bardales, Neil P. Lareau, Kasra Shamsaei, Branko Kosović, Negar Elhami-Khorasani, Eric P. James, and Hamed Ebrahimian
Nat. Hazards Earth Syst. Sci., 24, 47–52, https://doi.org/10.5194/nhess-24-47-2024, https://doi.org/10.5194/nhess-24-47-2024, 2024
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Following the destructive Lahaina Fire in Hawaii, our team has modeled the wind and fire spread processes to understand the drivers of this devastating event. The simulation results show that extreme winds with high variability, a fire ignition close to the community, and construction characteristics led to continued fire spread in multiple directions. Our results suggest that available modeling capabilities can provide vital information to guide decision-making during wildfire events.
Stephanie Mayer, Frank Techel, Jürg Schweizer, and Alec van Herwijnen
Nat. Hazards Earth Syst. Sci., 23, 3445–3465, https://doi.org/10.5194/nhess-23-3445-2023, https://doi.org/10.5194/nhess-23-3445-2023, 2023
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We present statistical models to estimate the probability for natural dry-snow avalanche release and avalanche size based on the simulated layering of the snowpack. The benefit of these models is demonstrated in comparison with benchmark models based on the amount of new snow. From the validation with data sets of quality-controlled avalanche observations and danger levels, we conclude that these models may be valuable tools to support forecasting natural dry-snow avalanche activity.
Wei Yang, Zhongyan Wang, Baosheng An, Yingying Chen, Chuanxi Zhao, Chenhui Li, Yongjie Wang, Weicai Wang, Jiule Li, Guangjian Wu, Lin Bai, Fan Zhang, and Tandong Yao
Nat. Hazards Earth Syst. Sci., 23, 3015–3029, https://doi.org/10.5194/nhess-23-3015-2023, https://doi.org/10.5194/nhess-23-3015-2023, 2023
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We present the structure and performance of the early warning system (EWS) for glacier collapse and river blockages in the southeastern Tibetan Plateau. The EWS warned of three collapse–river blockage chain events and seven small-scale events. The volume and location of the collapses and the percentage of ice content influenced the velocities of debris flows. Such a study is helpful for understanding the mechanism of glacier hazards and for establishing similar EWSs in other high-risk regions.
Alba Marquez Torres, Giovanni Signorello, Sudeshna Kumar, Greta Adamo, Ferdinando Villa, and Stefano Balbi
Nat. Hazards Earth Syst. Sci., 23, 2937–2959, https://doi.org/10.5194/nhess-23-2937-2023, https://doi.org/10.5194/nhess-23-2937-2023, 2023
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Only by mapping fire risks can we manage forest and prevent fires under current and future climate conditions. We present a fire risk map based on k.LAB, artificial-intelligence-powered and open-source software integrating multidisciplinary knowledge in near real time. Through an easy-to-use web application, we model the hazard with 84 % accuracy for Sicily, a representative Mediterranean region. Fire risk analysis reveals 45 % of vulnerable areas face a high probability of danger in 2050.
Elisabeth D. Hafner, Frank Techel, Rodrigo Caye Daudt, Jan Dirk Wegner, Konrad Schindler, and Yves Bühler
Nat. Hazards Earth Syst. Sci., 23, 2895–2914, https://doi.org/10.5194/nhess-23-2895-2023, https://doi.org/10.5194/nhess-23-2895-2023, 2023
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Oftentimes when objective measurements are not possible, human estimates are used instead. In our study, we investigate the reproducibility of human judgement for size estimates, the mappings of avalanches from oblique photographs and remotely sensed imagery. The variability that we found in those estimates is worth considering as it may influence results and should be kept in mind for several applications.
Gerardo Romano, Marco Antonellini, Domenico Patella, Agata Siniscalchi, Andrea Tallarico, Simona Tripaldi, and Antonello Piombo
Nat. Hazards Earth Syst. Sci., 23, 2719–2735, https://doi.org/10.5194/nhess-23-2719-2023, https://doi.org/10.5194/nhess-23-2719-2023, 2023
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The Nirano Salse (northern Apennines, Italy) is characterized by several active mud vents and hosts thousands of visitors every year. New resistivity models describe the area down to 250 m, improving our geostructural knowledge of the area and giving useful indications for a better understanding of mud volcano dynamics and for the better planning of safer tourist access to the area.
Harry Podschwit, William Jolly, Ernesto Alvarado, Andrea Markos, Satyam Verma, Sebastian Barreto-Rivera, Catherine Tobón-Cruz, and Blanca Ponce-Vigo
Nat. Hazards Earth Syst. Sci., 23, 2607–2624, https://doi.org/10.5194/nhess-23-2607-2023, https://doi.org/10.5194/nhess-23-2607-2023, 2023
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We developed a model of fire spread that assumes that fire spreads in all directions at a constant speed and is extinguished at a constant rate. The model was fitted to 1003 fires in Peru between 2001 and 2020 using satellite burned area data from the GlobFire project. We fitted statistical models that predicted the spread and extinguish rates based on weather and land cover variables and found that these variables were good predictors of the spread and extinguish rates.
Anushilan Acharya, Jakob F. Steiner, Khwaja Momin Walizada, Salar Ali, Zakir Hussain Zakir, Arnaud Caiserman, and Teiji Watanabe
Nat. Hazards Earth Syst. Sci., 23, 2569–2592, https://doi.org/10.5194/nhess-23-2569-2023, https://doi.org/10.5194/nhess-23-2569-2023, 2023
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All accessible snow and ice avalanches together with previous scientific research, local knowledge, and existing or previously active adaptation and mitigation solutions were investigated in the high mountain Asia (HMA) region to have a detailed overview of the state of knowledge and identify gaps. A comprehensive avalanche database from 1972–2022 is generated, including 681 individual events. The database provides a basis for the forecasting of avalanche hazards in different parts of HMA.
Caili Zhong, Sibo Cheng, Matthew Kasoar, and Rossella Arcucci
Nat. Hazards Earth Syst. Sci., 23, 1755–1768, https://doi.org/10.5194/nhess-23-1755-2023, https://doi.org/10.5194/nhess-23-1755-2023, 2023
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This paper introduces a digital twin fire model using machine learning techniques to improve the efficiency of global wildfire predictions. The proposed model also manages to efficiently adjust the prediction results thanks to data assimilation techniques. The proposed digital twin runs 500 times faster than the current state-of-the-art physics-based model.
Abby Morgan, Pascal Haegeli, Henry Finn, and Patrick Mair
Nat. Hazards Earth Syst. Sci., 23, 1719–1742, https://doi.org/10.5194/nhess-23-1719-2023, https://doi.org/10.5194/nhess-23-1719-2023, 2023
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The avalanche danger scale is a critical component for communicating the severity of avalanche hazard conditions to the public. We examine how backcountry recreationists in North America understand and use the danger scale for planning trips into the backcountry. Our results provide an important user perspective on the strengths and weaknesses of the existing scale and highlight opportunities for future improvements.
Adrián Cardíl, Victor M. Tapia, Santiago Monedero, Tomás Quiñones, Kerryn Little, Cathelijne R. Stoof, Joaquín Ramirez, and Sergio de-Miguel
Nat. Hazards Earth Syst. Sci., 23, 361–373, https://doi.org/10.5194/nhess-23-361-2023, https://doi.org/10.5194/nhess-23-361-2023, 2023
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This study aims to unravel large-fire behavior in northwest Europe, a temperate region with a projected increase in wildfire risk. We propose a new method to identify wildfire rate of spread from satellites because it is important to know periods of elevated fire risk for suppression methods and land management. Results indicate that there is a peak in the area burned and rate of spread in the months of March and April, and there are significant differences for forest-type land covers.
Liam S. Taylor, Duncan J. Quincey, and Mark W. Smith
Nat. Hazards Earth Syst. Sci., 23, 329–341, https://doi.org/10.5194/nhess-23-329-2023, https://doi.org/10.5194/nhess-23-329-2023, 2023
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Hazards from glaciers are becoming more likely as the climate warms, which poses a threat to communities living beneath them. We have developed a new camera system which can capture regular, high-quality 3D models to monitor small changes in glaciers which could be indicative of a future hazard. This system is far cheaper than more typical camera sensors yet produces very similar quality data. We suggest that deploying these cameras near glaciers could assist in warning communities of hazards.
Bastian Bergfeld, Alec van Herwijnen, Grégoire Bobillier, Philipp L. Rosendahl, Philipp Weißgraeber, Valentin Adam, Jürg Dual, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 23, 293–315, https://doi.org/10.5194/nhess-23-293-2023, https://doi.org/10.5194/nhess-23-293-2023, 2023
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For a slab avalanche to release, the snowpack must facilitate crack propagation over large distances. Field measurements on crack propagation at this scale are very scarce. We performed a series of experiments, up to 10 m long, over a period of 10 weeks. Beside the temporal evolution of the mechanical properties of the snowpack, we found that crack speeds were highest for tests resulting in full propagation. Based on these findings, an index for self-sustained crack propagation is proposed.
Sigrid Jørgensen Bakke, Niko Wanders, Karin van der Wiel, and Lena Merete Tallaksen
Nat. Hazards Earth Syst. Sci., 23, 65–89, https://doi.org/10.5194/nhess-23-65-2023, https://doi.org/10.5194/nhess-23-65-2023, 2023
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In this study, we developed a machine learning model to identify dominant controls of wildfire in Fennoscandia and produce monthly fire danger probability maps. The dominant control was shallow-soil water anomaly, followed by air temperature and deep soil water. The model proved skilful with a similar performance as the existing Canadian Forest Fire Weather Index (FWI). We highlight the benefit of using data-driven models jointly with other fire models to improve fire monitoring and prediction.
Yi Victor Wang and Antonia Sebastian
Nat. Hazards Earth Syst. Sci., 22, 4103–4118, https://doi.org/10.5194/nhess-22-4103-2022, https://doi.org/10.5194/nhess-22-4103-2022, 2022
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In this article, we propose an equivalent hazard magnitude scale and a method to evaluate and compare the strengths of natural hazard events across different hazard types, including earthquakes, tsunamis, floods, droughts, forest fires, tornadoes, cold waves, heat waves, and tropical cyclones. With our method, we determine that both the February 2021 North American cold wave event and Hurricane Harvey in 2017 were equivalent to a magnitude 7.5 earthquake in hazard strength.
Michael A. Storey and Owen F. Price
Nat. Hazards Earth Syst. Sci., 22, 4039–4062, https://doi.org/10.5194/nhess-22-4039-2022, https://doi.org/10.5194/nhess-22-4039-2022, 2022
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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 on predictions, with distance, temperature, wind speed and relative humidity also important. The models predicted reasonably accurately in comparison to other existing methods but would benefit from further development.
Tomás Calheiros, Akli Benali, Mário Pereira, João Silva, and João Nunes
Nat. Hazards Earth Syst. Sci., 22, 4019–4037, https://doi.org/10.5194/nhess-22-4019-2022, https://doi.org/10.5194/nhess-22-4019-2022, 2022
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Fire weather indices are used to assess the effect of weather on wildfires. Fire weather risk was computed and combined with large wildfires in Portugal. Results revealed the influence of vegetation cover: municipalities with a prevalence of shrublands, located in eastern parts, burnt under less extreme conditions than those with higher forested areas, situated in coastal regions. These findings are a novelty for fire science in Portugal and should be considered for fire management.
Ana C. L. Sá, Bruno Aparicio, Akli Benali, Chiara Bruni, Michele Salis, Fábio Silva, Martinho Marta-Almeida, Susana Pereira, Alfredo Rocha, and José Pereira
Nat. Hazards Earth Syst. Sci., 22, 3917–3938, https://doi.org/10.5194/nhess-22-3917-2022, https://doi.org/10.5194/nhess-22-3917-2022, 2022
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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 patch 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 creating fire-resilient Mediterranean landscapes.
Simon K. Allen, Ashim Sattar, Owen King, Guoqing Zhang, Atanu Bhattacharya, Tandong Yao, and Tobias Bolch
Nat. Hazards Earth Syst. Sci., 22, 3765–3785, https://doi.org/10.5194/nhess-22-3765-2022, https://doi.org/10.5194/nhess-22-3765-2022, 2022
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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, https://doi.org/10.5194/nhess-22-3501-2022, https://doi.org/10.5194/nhess-22-3501-2022, 2022
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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, https://doi.org/10.5194/nhess-22-3487-2022, https://doi.org/10.5194/nhess-22-3487-2022, 2022
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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, https://doi.org/10.5194/nhess-22-3247-2022, https://doi.org/10.5194/nhess-22-3247-2022, 2022
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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, https://doi.org/10.5194/nhess-22-3143-2022, https://doi.org/10.5194/nhess-22-3143-2022, 2022
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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.
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Short summary
We create multiple DEMs from photographs taken by helicopter and UAV and reveal the deposit volumes over the Langtang village, which was destroyed by avalanches induced by the Gorkha earthquake. Estimated snow depth in the source area is consistent with anomalously large snow depths observed at a neighboring glacier. Comparing with a long-term observational data, we conclude that this anomalous winter snow amplified the disaster induced by the 2015 Gorkha earthquake in Nepal.
We create multiple DEMs from photographs taken by helicopter and UAV and reveal the deposit...
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