Preliminary measurements and survey of snowdrift at the seehore avalanche test site - Aosta Valley (IT)

M. Maggioni (1) , N. Durand (2) , B. Frigo (3, 2) , O. Pallara (4) , M. Freppaz (1) , P. Dellavedova (2) , V. Segor (5) , F. Naaim-Bouvet (6) , H. Bellot (6)

1 DISAFA and NatRisk
2 aucun
3 Polito - Politecnico di Torino = Polytechnic of Turin
4 DAUIN - Dipartimento di Automatica e Informatica [Torino]
5 Ufficio Neve e Valanghe della Regione autonoma Valle d’ Aosta
6 UR ETGR (ETNA) - Erosion torrentielle neige et avalanches

In high elevation areas drifting snow influences the snowpack spatial distribution and consequently its stability. The amount of snow drifted from the windward side and accumulated on the leeward side is not only a function of wind conditions but it also depends on the snowpack characteristic. One of the aim of the project MAP3 "Monitoring for the Avalanche Prevision, Prediction and Protection" - P.O. ALCOTRA Italy/France (Alps) 2007-2013 is to better understand the influence of snowdrift on the snow spatial distribution in the leeward side of a ridge, where avalanches naturally or artificially occur. To achieve this aim, in Summer 2012 the Seehore avalanche test site in Aosta Valley (Italy) was implemented with a snow and weather station installed on the ridge at 2570m asl in order to measure wind speed and direction, snow depth and drifted snow at different heights above the ground. In case of avalanche release, snowpack properties and release features are recorded by field surveys. Laser scan measurements and photogrammetry are also performed to get information about the spatial distribution of the snowpack, with a special focus on the release zone. This paper presents the design and the installation of the system and the first results of the measurements. As the experimental device was fully operational only for four months during winter 2012- 2013, in this paper we focus on two specific events: 1) snowdrift event without snowfall, 2) snowdrift event with concurrent snowfall before an artificially released avalanche in the study site. More work is planned for the future, in particular concerning the avalanche release and snowpack features in respect to snowdrift conditions. This new experimental test site presents a great potentiality to advance in this research topic, due to its small size and relatively easy logistic in the data recording.

Mots clés: TRANSPORT DE NEIGE PAR LE VENT; ZONE DE DEPART D'AVALANCHE; DISPOSITIF EXPERIMENTAL; SITE D'AVALANCHE; ALPES ITALIENNES; SNOWDRIFT; AVALANCHE RELEASE ZONE; EXPERIMENTAL DATA

Domaines: Sciences de l'environnement

M. Maggioni, N. Durand, B. Frigo, O. Pallara, M. Freppaz, et al.. Preliminary measurements and survey of snowdrift at the seehore avalanche test site - Aosta Valley (IT). International Snow Science Workshop (ISSW), Oct 2013, Grenoble - Chamonix Mont-Blanc, France. p. 126 - p. 133. ⟨hal-00951282⟩