8.03.02 - Snow and avalanches


Michaela Teich, Austria


Dominik Kulakowski, United States

Momchil Panayotov, Bulgaria

About Unit

Heavy snowfall and snow avalanches play a major role for ecosystem dynamics and services in mountain forests. Forests can decrease the likelihood of avalanches starting and can thus protect large areas of human settlement and infrastructure.

The main aims of the working group are (i) to contribute to a better understanding of forest-snow interactions, and in particular of forest-avalanche interactions in mountain forests and (ii) to encourage communication and interaction among scientists with an interest in these topics.

State of Knowledge

1. Effects of snow cover and heavy snowfall: Structure and functioning of boreal and subalpine forests is greatly affected by snow cover and snowfall.  Snow cover duration is a critical factor that affects seedling survival in snow rich areas. Stem-breakage by heavy snowfall events can be major disturbance events and cause substantial economic damage.

2. Effects of avalanche disturbances on forests: Avalanches can damage or kill individual trees and forests that are located in vulnerable topographic settings. Avalanche disturbances typically result in forests that are characterized by smaller trees, shade intolerant species, greater structural diversity, and lower stem densities. Disturbed communities often provide unique habitats and can contribute to overall higher biodiversity. At a broader scale, avalanche tracks provide increased landscape heterogeneity and can serve as fire breaks.

3. Avalanche control by forests:  Forests can affect the likelihood of avalanches starting and can thus protect large areas of human settlement and infrastructure. Forests generally reduce the likelihood of avalanche disturbances in mountain environments, but the degree to which forests serve this function varies with stand structure

4. Climate- and land use-change: Changes in climate and  land-use affects forest cover and composition as well as snow avalanche disturbances.  This is likely to alter the location of areas where avalanches play an important role in forest dynamics. Changes in snow-duration and forest-cover expansion could also decrease albedo and would result in a positive feedback to climate warming.