Avalanches are a natural phenomenon that occurs every winter in areas where there is enough snow and the terrain is suitable for avalanches. In Norway, this means approximately 7 % of the country. Avalanches are triggered by a complex interplay between snow, weather and terrain. In addition, landslides can be triggered by human activities such as skiing or other steep terrain activity.
Every winter central road and railway sections are closed due to avalanches, and avalanches and avalanche danger mean that many people are evacuated from their homes. Statistic show that today there is an increasing tendency for fatal avalanche accidents to occur in connection with outdoor activities.
NGI's specialist expertise
Avalanche research is a broad field that includes many disciplines, including meteorology, physics/mechanics/mathematics, fluid-dynamics, numerical analysis, GIS (geographical information systems), geomorphology, statistics, geotechnics, as well as risk and risk assessment. Our special expertise comprises:
- knowledge of where and when an avalanche may occur
- calculation of speed, pressure effects and run-out distance of avalanches
- proposals and engineering design for protection measures.
Our core competence is a knowledge of the slide mechanism and the conditions which lead to avalanche. Meteorological (precipitation, winds and temperature) and topographical conditions are key factors. We have a close working relationship with the Norwegian Meteorological Institute.
NGI has its own avalanche research station, Fonnbu, in Grasdalen valley in the Strynefjell mountains, one of Norway's most avalanche-prone areas. Here, empirical data on snow and weather conditions are collected and compiled. All avalanches in the area are mapped.
On a nearby mountain slope, Ryggfonn, NGI has established its own avalanche path on which avalanches form naturally or can be triggered with explosive. Here, full-scale experiments with avalanches are carried out. Large tubular instrument masts are able to measure the speed and pressure effects of the avalanche, and the effect of the 16 m high catching dam on the valley floor.
Research and Development
The challenges and NGI research efforts relating to avalanches include:
- modelling and calculation of run-out distance and forces
- full-scale measurement of avalanches at Ryggfonn
- methods for surveying avalanche-prone areas
- new avalanche warning methods and emergency routines
- protective measures against avalanches, such as catching dams and snow fences.
NGI engages in international projects with expertise from France, Switzerland, Austria, Italy, the USA and Japan.
Services we offer with respect to avalanches
- Assisting local authorities in cases of acute avalanche risk
- Assessment of avalanches and slush avalanches
- Hazard and risk assessment
- Avalanche mapping
- Avalanche risk management
- Avalanche warnings (according to the international avalanche hazard scale)
- Planning of protective measures
- Courses, teaching and lectures.
Every year we send two experts to join the Norwegian Armed Forces Avalanche Group at the main NATO winter exercises.