Browsing Norwegian Geotechnical Institute (NGI) Digital Archive by Author "Kristensen, Krister"
Now showing items 1-20 of 54
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Activities of the Japanese-Norwegian collaboration of snow avalanche research during the winters 1990/1991 and 1991/1992. Final report
Bakkehøi, Steinar; Kristensen, Krister; Nishimur, Koichi; Norem, Harald; Sandersen, Frode (NGI-rapport;58120-29, Research report, 1993-03-05)The report gives a brief summary of the activities carried out by the Japanese - Norwegian collaboration on snow avalanche reasearch during the winters of 1990/1991 and 1991/1992. The research was mainly carried out in the ... -
Analysis of avalanche measurements out of the runout area of NGI's full-scale test-site Ryggfonn
Gauer, Peter; Lied, Karstein; Kristensen, Krister (Journal article, 2009)The paper summarizes measurements and observations of dry-snow avalanches at the Ryggfonn test-site with respect to their behavior in the runout area. Measurements of front velocities and retarding accelerations are presented ... -
Assessing the risk posed by natural hazards to infrastructures
Eidsvig, Unni; Kristensen, Krister; Vangelsten, Bjørn Vidar (Peer reviewed; Journal article, 2017)This paper proposes a model for assessing the risk posed by natural hazards to infrastructures, with a focus on the indirect losses and loss of stability for the population relying on the infrastructure. The model prescribes ... -
Avalanche characterization for regional forecasting
Kristensen, Krister; Kronholm, Kalle; Bjørdal, Nils H. (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2008)In the Sunnmøre and Romsdal road districts in Western Norway, the local road authorities have compiled a register of more than 300 sites where avalanches encounter principal roads in the area. The area covered is about 5 ... -
Avalanche forecasting and risk mitigation for specific objects at risk
Kristensen, Krister; Breien, Hedda; Lacasse, Suzanne (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2013)Objects and individuals can be exposed to different levels of avalanche hazard. For objectspecific avalanche forecasting and risk mitigation programs, the general danger scales, such as the European and North American ... -
An avalanche forecasting program based on a modified nearest neighbour method.
Kristensen, Krister; Larsson, Christer (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 1994)As a part of an avalanche forecasting system, a modified nearest neighbour program is described. The system is intended to be used with forecast values for most ofthe parameters. The modifications consist of 1) the use of ... -
An avalanche index for roads
Jonsson, Arni; Kristensen, Krister (Chapter, 2008)Several methods have been introduced through the years to evaluate avalanche risk along road sections. In 1988, Peter Schaerer introduced Avalanche Hazard Index, a numerical expression of damage and loss as the result of ... -
Avalanche observations at the Ryggfonn test site, Norway, with correlation to snow and weather conditions
Gauer, Peter; Kristensen, Krister (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2014)The Norwegian Geotechnical Institute (NGI) has been running full-scale avalanche experiments at the Ryggfonn test-site in western Norway for close to 40 years. Data from this period involve observations from about 32 ... -
Avalanche prediction and strength-of-knowledge assessment
Kristensen, Krister (Lecture, 2018)The NGI provides local avalanche forecasting, produces hazard maps and acts as an advisor for national and local authorities during emergencies. A main task is often to assess the likelihood of an avalanche reaching specific ... -
Avalanche rescue and mission risk in Norway 1996-2010
Lunde, Albert; Kristensen, Krister (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2013)Well documented data from Norwegian avalanche rescue missions are evaluated according to risk assessment. Data have been collected from police records and logs from joint rescue coordination centres. Mission risk assessments ... -
The avalanche situation in a special winter. Review of the 09/10 season in Norway.
Jaedicke, Christian; Brattlien, Kjetil; Frauenfelder, Regula; Kristensen, Krister; Kronholm, Kalle (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2010)The 2009/10 season featured significantly different snow conditions compared to the usually maritime snow pack in most of Norway. A stable high-pressure system over large parts of Europe led to low temperatures and limited ... -
Avalanche studies and model validation in Europe, SATSIE. Ryggfonn measurements winter 2004/2005
Kristensen, Krister (NGI-rapport;20021048-08, Research report, 2005-12-01)This report presents data collected from the full-scale avalanche test site Ryggfonn during the Winter 2004/2005. The weather and snow conditions are described and when possible, the avalanches have been characterized ... -
Can we learn more from the data underlying the statistical a-ß model with respect to the dynamical behavior of avalanches?
Gauer, Peter; Kronholm, Kalle; Lied, Karstein; Kristensen, Krister; Bakkehøi, Steinar (Journal article, 2010)Hazard and risk assessment in avalanche-prone areas involves estimation of runout distances of potential avalanches. Methods for determination of the runout may be divided into two categories: 1) methods based on statistical ... -
A comparison of avalanche models with data from dry-snow avalanches at Ryggfonn, Norway
Issler, Dieter; Harbitz, Carl Bonnevie; Kristensen, Krister; Lied, Karstein; Moe, Arne; Barbolini, M.; Khazaradze, G.; McElwaine, J.N.; Mears, A.I.; Naaim, M.; Sailer, R. (Chapter, 2005)Twelve well-documented dry-snow avalanches from the instrurnented Ryggfonn path in western Norway were selected for back-ca1culations with several dynamical avalanche models. In each case, the run-out distance, the front ... -
Design criteria for cylindrical masts exposed to snow creep forces.
Larsen, Jan Otto; Kristensen, Krister (NGI Publication;203, Chapter, 1998)Based on 23 years of measurements of snow creep forces on cylindrical masts, a relation between the pressure and snow parameters as snow depth, density and temperature, has been established. The long observation period has ... -
The diversities of large slushflows illustrated by selected cases.
Hestnes, Erik; Kristensen, Krister (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2010)Rapid mass movement of water-saturated snow, usually known as slushflow or slush avalanche, is a major natural hazard in Norway. The destructive forces are larger than those observed from other snow related mass flows of ... -
Fonnbu, a new (old) platform for snow and avalanche research.
Jaedicke, Christian; Kristensen, Krister; Lied, Karstein; Bakkehøi, Steinar (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2008)One of the first tasks of the newly established avalanche group at the NGI in 1973 was the selection of a suitable location for an avalanche research station. The choice was on Grasdalen, north of the Jotunheimen mountains, ... -
Forcasting snow avalanche days from meteorological data using classification trees; Grasdalen, Western Norway
Kronholm, Kalle; Vikhamar-Schuler, Dagrun; Jaedicke, Christian; Isaksen, Ketil; Sorteberg, Asgeir; Kristensen, Krister (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2006)Avalanches pose one of the most serious problems to infrastructure and people in the mountains in Norway. Processes leading to avalanche release are deterministic but the time and place of avalanche release is notoriously ... -
Forecasting snow avalanche days from meteorological data using classification trees, Grasdalen, Western Norway.
Kronholm, Kalle; Vikhamar-Schuler, Dagrun; Jaedicke, Christian; Isaksen, Ketil; Sorteberg, Asgeir; Kristensen, Krister (The International Snow Science Workshop (ISSW) Proceedings;, Chapter, 2006)Avalanches pose one of the most serious problems to infrastructure and people in the mountains in Norway. Processes leading to avalanche release are deterministic but the time and place of avalanche release is notoriously ... -
Four decades of observations from NGI’s full-scale avalanche test site Ryggfonn—Summary of experimental results
Gauer, Peter; Kristensen, Krister (Journal article, 2016)