Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

Abstract. The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1) to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2) to highlight the potential of Nothofagus pumilio tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

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A Reconstruction of Snow-Avalanche Characteristics in Montana, U.S.A., Using Vegetative Indicators

Journal of Glaciology ◽

10.1017/s0022143000006444 ◽

1985 ◽

Vol 31 (108) ◽

pp. 185-187 ◽

Cited By ~ 38

Author(s):

David R. Butler ◽

George P. Malanson

Keyword(s):

Tree Ring ◽

National Park ◽

Natural Hazard ◽

Snow Avalanche ◽

Glacier National Park ◽

Snow Avalanches ◽

Southern Boundary ◽

Tree Ring Data ◽

Wet Snow

AbstractWidespread wet-snow avalanches were observed on the southern boundary of Glacier National Park, Montana, in February 1979. Severe tilting, scarring, and breakage of trees were observed along a transverse trim-line of one path, 70 m from a wet-snow deposit. Tree-ring data were used to establish the date of occurrence, and the nature of damage was used to characterize the avalanche event. The event probably included a previously unrecognized dry-snow avalanche and associated wind blast. Such events present different problems for natural-hazard planning. The nature of vegetative damage along the margins of avalanche paths is shown to be a useful indicator of the characteristics of past unobserved avalanche events.

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Controller for a Low-Altitude Fixed-Wing UAV on an Embedded System to Assess Specific Environmental Conditions

International Journal of Aerospace Engineering ◽

10.1155/2020/1360702 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Johannes von Eichel-Streiber ◽

Christoph Weber ◽

Jesús Rodrigo-Comino ◽

Jens Altenburg

Keyword(s):

Embedded System ◽

Environmental Conditions ◽

Plant Density ◽

Future Research ◽

Digital Elevation ◽

Small Uav ◽

Aerial Vehicle ◽

Low Costs ◽

Low Altitude ◽

Elevation Model

The use of an appropriate sensor on an unmanned aerial vehicle (UAV) is vital to assess specific environmental conditions successfully. In addition, technicians and scientists also appreciate a platform to carry the sensors with some advantages such as the low costs or easy pilot management. However, extra requirements like a low-altitude flight are necessary for special applications such as plant density or rice yield. A rotary UAV matches this requirement, but the flight endurance is too short for large areas. Therefore, in this article, a fixed-wing UAV is used, which is more appropriate because of its longer flight endurance. It is necessary to develop an own controller system to use special sensors such as Lidar or Radar on the platform as a multifunctionality system. Thereby, these sensors are used to generate a digital elevation model and also as a collision avoidance sensor at the same time. To achieve this goal, a small UAV was equipped with a hardware platform including a microcontroller and sensors. After testing the system and simulation, the controller was converted into program code to implement it on the microcontroller. After that, several real flights were performed to validate the controller and sensors. We demonstrated that the system is able to work and match the high requirements for future research.

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Reconstructing snow-avalanche activity with tree rings in Maramureş Mountains (Eastern Carpathians, Romania)

10.5194/egusphere-egu2020-20060 ◽

2020 ◽

Author(s):

Armelle Decaulne ◽

Ionela-Georgiana Răchită ◽

Mihai Hotea ◽

Vasile Timur Chiş ◽

Olimpiu Traian Pop

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Climatic Factors ◽

Climatic Conditions ◽

Snow Avalanche ◽

Snow Avalanches ◽

Joint Research ◽

Eastern Carpathians ◽

Joint Research Project ◽

Callus Tissues

Snow avalanches represent a common phenomenon in Maramure&#351; Mountains (Eastern Carpathians, Romania) where they occur frequently on higher steep slopes and reach in the runout zones the valley bottoms below 1000 m a.s.l. The presence of particular topo-climatic conditions influences the patterns of avalanche activity in terms of past frequency and spatial extent along the slope valleys. As the past snow-avalanche activity is not documented by written reports in the area, reliable information about avalanche history is missing. However, the slopes are forested, trees repeatedly disturbed by snow avalanches record evidence of past events. For this study we reconstructed the avalanche activity using tree rings as a source of proxy data. To date the snow-avalanche history, dendrochronological investigations have been carried out in two avalanche paths, along which living trees showed clear external signs of past disturbances related to mechanical impacts produced by snow avalanches. In each investigated path, a total number of 52 and respectively 118 trees have been sampled and their spatial position recorded with a GPS device. Tree-growth anomalies (e.g. scars, callus tissues, the onset sequences of tangential rows of traumatic resin ducts, compression wood, growth suppression and release sequences) related to snow avalanche disturbance identified within tree rings served to reconstruct past events with an annual resolution. The results indicate that, apart the 2005 major event witnessed and also confirmed by tree-ring dating, multiple other events have been reconstructed since the beginning of 20th century. Despite some inherent limitations of tree-ring methods in reconstructing past avalanche events, these dendrochronological investigations confirm their utility in deciphering the patterns of avalanche activity in Maramure&#351; Mountains. Tree-ring studies contribute to a better understanding of the role of topographical and climatic factors which influence the spatio-temporal occurrence of snow avalanches.This study represents a contribution to the joint research project 09-AUF, &#8216;&#8216;Activit&#233; des avalanches de neige dans les Carpates Orientales Roumaines et Ukrainiennes - ACTIVNEIGE&#8217;&#8217;, co-funded by the Agence Universitaire de la Francophonie (AUF) and Institutul de Fizic&#259; Atomic&#259; (IFA), Romania.

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Quaternary formations mapping in the region of Volta Grande do Rio Uruguai (Brazil)

Geography Department University of Sao Paulo ◽

10.11606/eissn.2236-2878.rdg.2021.174174 ◽

2021 ◽

Vol 41 ◽

pp. e174174

Author(s):

Sandra Cristina Deodoro ◽

William Zanete Bertolini ◽

Plinio da Costa Temba

Keyword(s):

Particle Size Analysis ◽

Size Analysis ◽

Valley Bottom ◽

Model Soil ◽

Fluvial Dynamics ◽

Digital Elevation ◽

Topographic Attributes ◽

History Of ◽

Elevation Model

Quaternary formations (detrital and weathered materials) are an important natural resource for different areas of scientific investigation, from understanding their relation to erosive processes and morphodynamic processes that create landforms or to understanding the history of the first human settlements (geoarcheology). Quaternary coverings can be formed in situ or be transported by external geologic agents. Regarding soils, Quaternary formations are related to landscape topography and are transformed according to the characteristics of this topography. Hence, classifying and mapping these soils is not always easy. The present article aims to map the Quaternary formations along a stretch of the Uruguay River basin known as Volta Grande (SC/RS-Brazil), by using topographic attributes derived from the SRTM GL1-Up Sampled digital elevation model, soil particle-size analysis, and a generated Multiresolution Index of Valley Bottom Flatness (MRVBF) index . The results of the analysis show that: (i) colluvium is the predominant Quaternary formation in the study area; (ii) there is a predominance of clay, corroborating previous studies of the region; (iii) the spatial distribution of the study area’s Quaternary formations reflect local slope dynamics based on morphology and topographic position; and, (iv) the existence of colluvium-alluvium on the Uruguay River’s banks indicates that slope attributes contributed to the pedogeomorphological dynamics of the study area and not only fluvial dynamics. Based on the results, the methodology applied in this study might be useful for pedogeomorphological studies, notably in the analysis and mapping of Quaternary formations, despite some of its limitations.

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Volkanostratigrafi Inderaan Jauh Kompleks Gunungapi Gede dan Sekitarnya, Jawa Barat, Indonesia

Jurnal Geologi dan Sumberdaya Mineral ◽

10.33332/jgsm.v20i1.386 ◽

2019 ◽

Vol 20 (1) ◽

pp. 9

Author(s):

Fitriani Agustin ◽

Sutikno Bronto

Keyword(s):

Remote Sensing ◽

Geological Mapping ◽

Lava Flows ◽

Energy Resources ◽

Visual Interpretation ◽

Remote Sensing Technology ◽

Sensing Technology ◽

Digital Elevation ◽

History Of ◽

Elevation Model

Remote sensing technology greatly helps to identify the various of volcano features, including active, old and ancient volcanoes. The aim of this paper is intended to introduce various volcanic features in the Gede Volcano Complexs (GVC) and souronding area; compose volcanostratigraphy; and estimate the history of the volcanoes. The method used is a visual interpretation 9 meters spatial resolution of Digital Elevation Model (DEM) TerraSar-x image. Indonesian Stratigraphy Nomenclature Guide 1996 was implemented in vocanostratigraphy unit classification, involving Arc, Super Brigate, Brigate, Crown and Hummockly. Based on the interpretation the DEM image, volcanostratigraphic unit the Gede Volcano Complex consists of Bregade Masigit (Br. M.), which consists of Joklok (Gm.J.) and Gegerbentang (Gm.G.) Hummocs; Crown Lingkung (Kh.L.) consisting of Pangrango (Gm.P.), Situ Gunung (Gm Sg.), Cikahuripan (Gm.Ck.), Pasir Prahu (Gm.Ph) Hummocs; Gege Crown (Kh.G.), which is located in the east of Lingkung Crown. The Gede Crown consists of Gumuruh humock (Gm.Gh.), Gunung Gede lava flows (LG 1,2,3,4,5), and giant debrise avalances (gv-G). The geological mapping based volcanostratigraphy is very useful for exploration of mineral and energy resources, as well as geological hazards.Keywords : volcanostratigraphy, DEM TerraSar-x image, Gunung Gede Complexs.

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Digital Segusio: from models generation to urban reconstruction

Virtual Archaeology Review ◽

10.4995/var.2016.5874 ◽

2016 ◽

Vol 7 (15) ◽

pp. 87

Author(s):

Antonia Spanò ◽

Filiberto Chiabrando ◽

Livio Dezzani ◽

Antonio Prencipe

Keyword(s):

Laser Scanning ◽

Urban Landscape ◽

Geographical Information ◽

Innovative Methods ◽

Digital Elevation ◽

History Of ◽

Land Survey ◽

Aerial Vehicle ◽

Elevation Model ◽

The City

The reconstructive study of the urban arrangement of Susa in the 4th century arose from the intention to exploit some resources derived from local studies, and survey activities, fulfilled by innovative methods from which the modelling of architectural heritage (AH) and virtual reconstructions are derived. The digital Segusio presented in this paper is the result of intensive discussion and exchange of data and information during the urban landscape documentation activities, and due to the technology of virtual model generation, making it possible to recreate the charm of an ancient landscape. The land survey has been accomplished using aerial and terrestrial acquisition systems, mainly through digital photogrammetry from UAV (Unmanned Aerial Vehicle) and terrestrial laser scanning. Results obtained from both the methods have been integrated into the medium scale geographical data from the regional map repository, and some processing and visualization supported by GIS (Geographical Information System) has been achieved. Subsequently, with the help of accurate and detailed DEM (Digital Elevation Model) and other architectural scale models related to the ancient heritage, this ancient landscape was modelled. The integration of the history of this city with digital and multimedia resources will be offered to the public in the city museum housed in the restored castle of Maria Adelaide (Savoy dynasty, 11th century), which stands in the place where the acropolis of the city of Susa lay in ancient times.

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Tree-ring dating of snow avalanche history in Parâng Mountains (Southern Carpathians, Romania)

10.5194/egusphere-egu2020-587 ◽

2020 ◽

Author(s):

Corina Todea ◽

Olimpiu Pop

Keyword(s):

Tree Ring ◽

Snow Avalanche ◽

Mountainous Area ◽

Snow Avalanches ◽

The Past ◽

Avalanche Hazard ◽

Hiking Trails ◽

Traumatic Resin Ducts ◽

Tree Ring Data ◽

Southern Carpathians

In high mountainous areas worldwide, snow avalanches represent one of the main morphodynamic processes which influence the morphology of steep slopes. They usually disturb the forests, and represent a significant natural hazard that may endanger the safety of tourists exposed along the hiking trails crossing the avalanche-prone slopes. In the context of the growing tourism activities in the area where tourist become exposed to snow avalanche hazard, there is need for detailed analysis for documenting the past activity of this geomorphic process, especially in remote areas where historical data is lacking. Such mountainous area without snow avalanche monitoring and archival records is in Par&#226;ng Mountains (Southern Carpathians, Romania). On forested slopes, trees disturbed by snow-avalanches may record in their growth rings information about the past event occurrence. The main aim of this study is to improve the knowledge about the past snow avalanche history using tree-rings approach. To this end, 57 disturbed spruce (Picea abies (L.) Karst.) trees growing along an avalanche path located on the western slopes of the Par&#226;ng Mountains were sampled and their growth disturbances (scars, traumatic resin ducts, compression wood and growth suppression sequences) served to reconstruct the snow-avalanche history back to 1950. Tree-ring analyses allowed reconstructing a minimum of 14 snow avalanche events which occurred in the past along the investigated path. The tree-ring approach presented in this study proved to be a valuable tool in reconstructing snow avalanche history and compliting the snow avalanche database in Par&#226;ng Mountains. The number and spatial extent of documented snow avalanches evidence the potential snow avalanche hazards in the study area. The tree-ring data from the present study, together with those presented by the previous studies in the study area may further contribute to the snow avalanche hazard assessment.&#160;

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A Reconstruction of Snow-Avalanche Characteristics in Montana, U.S.A., Using Vegetative Indicators

Journal of Glaciology ◽

10.3189/s0022143000006444 ◽

1985 ◽

Vol 31 (108) ◽

pp. 185-187 ◽

Cited By ~ 1

Author(s):

David R. Butler ◽

George P. Malanson

Keyword(s):

Tree Ring ◽

National Park ◽

Natural Hazard ◽

Snow Avalanche ◽

Glacier National Park ◽

Snow Avalanches ◽

Southern Boundary ◽

Tree Ring Data ◽

Wet Snow

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The Evolution of the Popocatépetl Volcanic Complex: Constraints on Periodic Edifice Construction and Destruction by Sector Collapse

Journal of the Geological Society ◽

10.1144/jgs2021-022 ◽

2021 ◽

pp. jgs2021-022

Author(s):

Guillem Gisbert ◽

Hugo Delgado-Granados ◽

Martin Mangler ◽

Julie Prytulak ◽

Ramón Espinasa-Pereña ◽

...

Keyword(s):

Aerial Imagery ◽

Volcanic Complex ◽

Sector Collapse ◽

Content Type ◽

Digital Elevation ◽

History Of ◽

Supplementary Material ◽

Complex Constraints ◽

Elevation Model ◽

First Time

Popocatépetl is one of the most active volcanoes in North America. Its current predominantly mild activity is contrasted by a history of large effusive and explosive eruptions and sector collapse events, which was first summarised by Espinasa-Pereña and Martin-Del Pozzo (2006). Since then, a wealth of new radiometric, geophysical and volcanological data has been published, requiring a re-evaluation of the evolution of the Popocatépetl Volcanic Complex (PVC). Herein, we combine existing literature with new field observations, aerial imagery and digital elevation model interpretations to produce an updated and improved reconstruction of the growth and evolution of the PVC through all of its history. This will be fundamental for the assessment and mitigation of risks associated with potential future high-magnitude activity of the PVC. The PVC consists of four successive volcanic edifices separated by three sector collapse events producing avalanche deposits: Tlamacas (>538 - >330 ka, described here for the first time), Nexpayantla (∼330 - >96 ka), Ventorrillo (∼96 ka - 23.5 ka) and Popocatépetl (<23.5ka) edifices. The newly described Tlamacas collapse propagated towards ENE forming part of the Mayorazgo avalanche deposit.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5709190

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Sensitivity of snow avalanche simulations to digital elevation model quality and resolution

Annals of Glaciology ◽

10.3189/172756411797252121 ◽

2011 ◽

Vol 52 (58) ◽

pp. 72-80 ◽

Cited By ~ 42

Author(s):

Yves Bühler ◽

Marc Christen ◽

Julia Kowalski ◽

Perry Bartelt

Keyword(s):

Spatial Resolution ◽

Large Scale ◽

Three Dimensional ◽

Test Site ◽

Snow Avalanche ◽

Model Quality ◽

Digital Elevation ◽

Elevation Model ◽

Dynamics Simulations ◽

Simulation Parameters

AbstractDigital elevation models (DEMs), represent the three-dimensional terrain and are the basic input for numerical snow avalanche dynamics simulations. DEMs can be acquired using topographic maps or remote-sensing technologies, such as photogrammetry or lidar. Depending on the acquisition technique, different spatial resolutions and qualities are achieved. However, there is a lack of studies that investigate the sensitivity of snow avalanche simulation algorithms to the quality and resolution of DEMs. Here, we perform calculations using the numerical avalance dynamics model RAMMS, varying the quality and spatial resolution of the underlying DEMs, while holding the simulation parameters constant. We study both channelized and open-terrain avalanche tracks with variable roughness. To quantify the variance of these simulations, we use well-documented large-scale avalanche events from Davos, Switzerland (winter 2007/08), and from our large-scale avalanche test site, Vallée de la Sionne (winter 2005/06).We find that the DEM resolution and quality is critical for modeled flow paths, run-out distances, deposits, velocities and impact pressures. Although a spatial resolution of ∼25m is sufficient for large-scale avalanche modeling, the DEM datasets must be checked carefully for anomalies and artifacts before using them for dynamics calculations.

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