The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche

On 8th February 1996, in the north-western part of Andorra in the Pyrenees, the Les Fonts d’Arinsal (LFd’A) pure powder avalanche was triggered, descending some 1200 m to the bottom of the Arinsal valley and continuing up the opposite slope for about 200 m. This size 4–5 avalanche reached velocities...

Full description

Bibliographic Details
Main Authors: Glòria Furdada, Aina Margalef, Laura Trapero, Marc Pons, Francesc Areny, Margaret Baró, Albert Reyes, Marta Guinau
Format: Article
Language:English
Published: MDPI AG 2020-03-01
Series:Geosciences
Subjects:
Online Access:https://www.mdpi.com/2076-3263/10/4/126
id doaj-986f6f2261cc49a28b051db16be1decc
record_format Article
spelling doaj-986f6f2261cc49a28b051db16be1decc2020-11-25T01:47:56ZengMDPI AGGeosciences2076-32632020-03-011012612610.3390/geosciences10040126The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow AvalancheGlòria Furdada0Aina Margalef1Laura Trapero2Marc Pons3Francesc Areny4Margaret Baró5Albert Reyes6Marta Guinau7RISKNAT Research Group, Geomodels Institute, Department of Earth and Ocean Dynamics, University of Barcelona, 08028 Barcelona, SpainSnow and Mountain Research Centre of Andorra (CENMA-IEA), AD600 Sant Julià de Lòria, AndorraSnow and Mountain Research Centre of Andorra (CENMA-IEA), AD600 Sant Julià de Lòria, AndorraSnow and Mountain Research Centre of Andorra (CENMA-IEA), AD600 Sant Julià de Lòria, AndorraDepartment of Industry and Transport, Ministry of Economy, Andorra Government (until 2006), c/Prat de la Creu 62–64, AD500 Andorra la Vella, AndorraASI Consultants (until 2003), Camí de l’Església Cs Joan PB-1, AD300 Anyós, AndorraCamp de Neu Ordino-Arcalís, Grandvalira Resorts, AD300 El Serrat, AndorraRISKNAT Research Group, Geomodels Institute, Department of Earth and Ocean Dynamics, University of Barcelona, 08028 Barcelona, SpainOn 8th February 1996, in the north-western part of Andorra in the Pyrenees, the Les Fonts d’Arinsal (LFd’A) pure powder avalanche was triggered, descending some 1200 m to the bottom of the Arinsal valley and continuing up the opposite slope for about 200 m. This size 4–5 avalanche reached velocities of up to 80 ms<sup>−1</sup>, devastated 18 ha of forest, involved a minimum volume of up to 1.8 × 10<sup>6</sup> m<sup>−3</sup> and caused major damage to eight buildings. Fortunately, no one was injured thanks to an evacuation, but 322 people lost their properties. This study describes the physical characteristics of the LFd’A avalanche path and provides data on earlier avalanches, the meteorological synoptic situation and snowpack conditions that generated the avalanche episode, the warning and preventive actions carried out, the effects and evidence of the large avalanche, and the defence system implemented afterwards. A discussion of the avalanche dynamics based on observations and damage, including the role of snow entrainment, the total lack of characteristic dense flow deposits, as well as the evidence of a two-phase flow (fluidisation and suspension), is presented. This case study is an example of a paradigmatic large, pure powder, dry-snow avalanche, which will be useful for model calibration.https://www.mdpi.com/2076-3263/10/4/126snow avalanchespowder snow avalanchefield observationssnow entrainmentcase studyPyrenees
collection DOAJ
language English
format Article
sources DOAJ
author Glòria Furdada
Aina Margalef
Laura Trapero
Marc Pons
Francesc Areny
Margaret Baró
Albert Reyes
Marta Guinau
spellingShingle Glòria Furdada
Aina Margalef
Laura Trapero
Marc Pons
Francesc Areny
Margaret Baró
Albert Reyes
Marta Guinau
The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
Geosciences
snow avalanches
powder snow avalanche
field observations
snow entrainment
case study
Pyrenees
author_facet Glòria Furdada
Aina Margalef
Laura Trapero
Marc Pons
Francesc Areny
Margaret Baró
Albert Reyes
Marta Guinau
author_sort Glòria Furdada
title The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
title_short The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
title_full The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
title_fullStr The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
title_full_unstemmed The Avalanche of Les Fonts d’Arinsal (Andorra): An Example of a Pure Powder, Dry Snow Avalanche
title_sort avalanche of les fonts d’arinsal (andorra): an example of a pure powder, dry snow avalanche
publisher MDPI AG
series Geosciences
issn 2076-3263
publishDate 2020-03-01
description On 8th February 1996, in the north-western part of Andorra in the Pyrenees, the Les Fonts d’Arinsal (LFd’A) pure powder avalanche was triggered, descending some 1200 m to the bottom of the Arinsal valley and continuing up the opposite slope for about 200 m. This size 4–5 avalanche reached velocities of up to 80 ms<sup>−1</sup>, devastated 18 ha of forest, involved a minimum volume of up to 1.8 × 10<sup>6</sup> m<sup>−3</sup> and caused major damage to eight buildings. Fortunately, no one was injured thanks to an evacuation, but 322 people lost their properties. This study describes the physical characteristics of the LFd’A avalanche path and provides data on earlier avalanches, the meteorological synoptic situation and snowpack conditions that generated the avalanche episode, the warning and preventive actions carried out, the effects and evidence of the large avalanche, and the defence system implemented afterwards. A discussion of the avalanche dynamics based on observations and damage, including the role of snow entrainment, the total lack of characteristic dense flow deposits, as well as the evidence of a two-phase flow (fluidisation and suspension), is presented. This case study is an example of a paradigmatic large, pure powder, dry-snow avalanche, which will be useful for model calibration.
topic snow avalanches
powder snow avalanche
field observations
snow entrainment
case study
Pyrenees
url https://www.mdpi.com/2076-3263/10/4/126
work_keys_str_mv AT gloriafurdada theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT ainamargalef theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT lauratrapero theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT marcpons theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT francescareny theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT margaretbaro theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT albertreyes theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT martaguinau theavalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT gloriafurdada avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT ainamargalef avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT lauratrapero avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT marcpons avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT francescareny avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT margaretbaro avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT albertreyes avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
AT martaguinau avalancheoflesfontsdarinsalandorraanexampleofapurepowderdrysnowavalanche
_version_ 1725013866080894976