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

Abstract

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 Correspondence to: A. Casteller (casteller@lab.cricyt.edu.ar) 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.

Implications of spatial distribution of rockfall reconstructed by dendrogeomorphological methods

“…This technique has successfully been applied to the spatio-temporal analysis of debris-flow activity (Bollschweiler et al, 2007;Pelfini and Santilli, 2008;Šilhán and Pánek, 2010;Stoffel, 2010), snow avalanches (Butler and Sawyer, 2008;Casteller et al, 2008), landslides (Fantucci and Sorriso-Valvo, 1999;Stefanini, 2004;Lopez-Saez et al, 2012a, b;Šilhán et al, 2013) and gully erosion (Corona et al, 2011;Stoffel et al, 2012). The great advantage of dendrogeomorphic methods is that they allow rapid acquisition of data, which is otherwise accessible only by means of long-term field monitoring.…”

La aplicación del análisis de los anillos de crecimiento a interrogantes ecológicos: Un breve repaso de la Dendroecología en Hispanoamérica

“…El uso de técnicas dendroecológicas ha permitido la reconstrucción y datación de diferentes tipos de perturbaciones. Para el caso de los eventos avalanchas de nieve, son pioneros los trabajos en los bosques de Nothofagus pumliio en los Andes patagónicos de Argentina que permitieron la reconstrucción temporal y espacial de este tipo de eventos (Mundo et al 2007, Casteller et al 2008. En estos mismos bosques, estas técnicas permitieron reconstruir la historia de caídas masivas de árboles ocasionadas por fuertes tormentas y comprender la influencia de esta perturbación en la dinámica de estos bosques (Rebertus et al 1997).…”

Assessing the interaction between mountain forests and natural hazards at Nevados de Chillán, Chile, and its implications for Ecosystem-based Disaster Risk Reduction

“…The use of the new model RAMMS::Avalanche (that considers forest effects), developed and first tested in the Alps, was used in this investigation to reconstruct past avalanche events and to determine potential avalanche scenarios. Such simulations, with a few exceptions (Casteller et al, 2008), are practically non-existent in the Andes. This type of multi-methodological approach has proven to be most effective (Gądek et al, 2017), in particular in regions where documentary data of past events is 20…”