scholarly journals Field experiments on “living” snow fences

1998 ◽  
Vol 26 ◽  
pp. 217-220 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Pierre Mullenbach
Keyword(s):  
Field Experiments ◽  
Snow Accumulation ◽  
Real Problem ◽  
Effective Height ◽  
Natural Plant ◽  
Drifting Snow ◽  
Snow Fence ◽  
Limited Scale ◽  
Living Fences ◽  
Snow Fences

In Franee, drifting snow is generally controlled using artificial snow fences. Living snow fences are not a new concept but they have only been used on a limited scale. Research directly related to natural plant barriers is limited. We therefore decided to study the behaviour of species that would survive and grow satisfactorily in the French Alps.In the first experiment, we compared the storage capacity of several different kinds of living fences consisting of pruned spruces, unpruned spruces and sorbs.Field observations during the winter of 1995-96 proved that deciduous trees such as sorbs are effective, and that pruning the lower 50 cm is not effective at the end of the season because of the weight of snow on low branches.However, the use of natural plant barriers has disadvantages: a living snow fence takes time to reach an effective height and is difficult to establish on windy sites at a high altitude. This is a real problem. Therefore, in a second experiment, we studied the death rate of larches planted behind a fence. We noticed that the snow fence had several effects, snow accumulation (until the planted trees grew up) and protection of the planted trees.

scholarly journals Field experiments on “living” snow fences

1998 ◽  
Vol 26 ◽  
pp. 217-220 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Pierre Mullenbach
Keyword(s):  
Field Experiments ◽  
Snow Accumulation ◽  
Real Problem ◽  
Effective Height ◽  
Natural Plant ◽  
Drifting Snow ◽  
Snow Fence ◽  
Limited Scale ◽  
Living Fences ◽  
Snow Fences

In Franee, drifting snow is generally controlled using artificial snow fences. Living snow fences are not a new concept but they have only been used on a limited scale. Research directly related to natural plant barriers is limited. We therefore decided to study the behaviour of species that would survive and grow satisfactorily in the French Alps.In the first experiment, we compared the storage capacity of several different kinds of living fences consisting of pruned spruces, unpruned spruces and sorbs.Field observations during the winter of 1995-96 proved that deciduous trees such as sorbs are effective, and that pruning the lower 50 cm is not effective at the end of the season because of the weight of snow on low branches.However, the use of natural plant barriers has disadvantages: a living snow fence takes time to reach an effective height and is difficult to establish on windy sites at a high altitude. This is a real problem. Therefore, in a second experiment, we studied the death rate of larches planted behind a fence. We noticed that the snow fence had several effects, snow accumulation (until the planted trees grew up) and protection of the planted trees.

scholarly journals Snow-Fence Experiments in Alpine Areas

1973 ◽  
Vol 12 (65) ◽  
pp. 291-303
Author(s):  
M. Martinelli
Keyword(s):  
Rocky Mountains ◽  
Stream Flow ◽  
Snow Accumulation ◽  
Snow Fence ◽  
Colorado Rocky Mountains ◽  
Natural Snow ◽  
Snow Fences ◽  
Sloping Terrain

AbstractSnow fences built up-wind of natural snowdrifts at four alpine sites in the Colorado Rocky Mountains changed snow accumulation appreciably. The 3 m tall fences increased the amount of snow at three sites but decreased it at the fourth. At two of the three sites where snow was increased, there was no change in melt rate, so the additional snow prolonged the melt period 1–3 weeks. Fences most successfully augmented natural snow accumulation at sites with level or gently sloping terrain down-wind from the accumulation site. Between 15 and 30 m of fence was needed to produce an extra 1000 m3 of water equivalent in the snowfields at the beginning of the melt season. Fences of the type described here, if properly located, are a means of increasing summer stream flow from alpine areas.

scholarly journals Design Criteria and Location of Snow Fences

1985 ◽  
Vol 6 ◽  
pp. 68-70
Author(s):  
Harald Norem
Keyword(s):  
Minimum Distance ◽  
Storage Capacity ◽  
Windward Side ◽  
Design Criteria ◽  
Total Density ◽  
Design Considerations ◽  
Drifting Snow ◽  
Snow Fence ◽  
Snow Model ◽  
Snow Fences

The paper describes experience gained in Norway regarding the design criteria and use in practice of snow fences. The paper is based on theoretical studies on drifting snow, model experiments and experience accumulated through practical consulting work.Snow fence design is a compromise between the storage capacity and minimization of dimensioning forces. Design considerations include fence height H, total snow fence density, and the gap between ground and fence. A gap of 0.15H - 0.2H and a total density of 45% are usually recommended. On ridge crests the gap can be reduced to 0.1H and in areas where snow depths exceed 2.0 m, it can be increased to 0.3H. In such cases the fence density should be varied such that the total density, including the gap, will remain near 45%. The height of the snow fences should be kept within 3.5 -4.5 m and the snow fences should be erected on the windward side of obstacles that create snowdrifts. The minimum distance from fence to road should not be less than 15H; in certain circumstances in coastal climate, this can be reduced to 10H.

Use of Snow Fences to Reduce the Impacts of Snowdrifts on Highways: Renewed Perspective

2017 ◽  
Vol 2613 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Sen Du ◽  
John Petrie ◽  
Xianming Shi
Keyword(s):  
Road Safety ◽  
Right Of Way ◽  
Drifting Snow ◽  
Snow Fence ◽  
Survey Results ◽  
Snow Fences ◽  
The Right ◽  
Survey Responses ◽  
Almost All ◽  
Departments Of Transportation

In northern climates, snow fences are usually established in or beyond the right-of-way to eliminate blowing and drifting snow on roadways and thus improve road safety. To make snow fences more effective on highways and provide guidelines for the departments of transportation siting the fences, this work reviews the literature as well as survey responses from practitioners in northern states. This review combines information obtained from the resources to detail several aspects of snow fence use, including history, design protocols, siting policies, benefits, challenges, and numerical modeling. Particular attention is paid to living snow fences as an alternative to traditional structural snow fences. The survey results show that almost all the responding agencies have launched snow fence programs, which have various design and siting protocols that depend on the specific conditions.

scholarly journals Snow-Fence Experiments in Alpine Areas

1973 ◽  
Vol 12 (65) ◽  
pp. 291-303 ◽  
Author(s):  
M. Martinelli
Keyword(s):  
Rocky Mountains ◽  
Stream Flow ◽  
Snow Accumulation ◽  
Snow Fence ◽  
Colorado Rocky Mountains ◽  
Natural Snow ◽  
Snow Fences ◽  
Sloping Terrain

Abstract Snow fences built up-wind of natural snowdrifts at four alpine sites in the Colorado Rocky Mountains changed snow accumulation appreciably. The 3 m tall fences increased the amount of snow at three sites but decreased it at the fourth. At two of the three sites where snow was increased, there was no change in melt rate, so the additional snow prolonged the melt period 1–3 weeks. Fences most successfully augmented natural snow accumulation at sites with level or gently sloping terrain down-wind from the accumulation site. Between 15 and 30 m of fence was needed to produce an extra 1000 m3 of water equivalent in the snowfields at the beginning of the melt season. Fences of the type described here, if properly located, are a means of increasing summer stream flow from alpine areas.

scholarly journals Design Criteria and Location of Snow Fences

1985 ◽  
Vol 6 ◽  
pp. 68-70 ◽  
Author(s):  
Harald Norem
Keyword(s):  
Minimum Distance ◽  
Storage Capacity ◽  
Windward Side ◽  
Design Criteria ◽  
Total Density ◽  
Design Considerations ◽  
Drifting Snow ◽  
Snow Fence ◽  
Snow Model ◽  
Snow Fences

The paper describes experience gained in Norway regarding the design criteria and use in practice of snow fences. The paper is based on theoretical studies on drifting snow, model experiments and experience accumulated through practical consulting work. Snow fence design is a compromise between the storage capacity and minimization of dimensioning forces. Design considerations include fence height H, total snow fence density, and the gap between ground and fence. A gap of 0.15H - 0.2H and a total density of 45% are usually recommended. On ridge crests the gap can be reduced to 0.1H and in areas where snow depths exceed 2.0 m, it can be increased to 0.3H. In such cases the fence density should be varied such that the total density, including the gap, will remain near 45%. The height of the snow fences should be kept within 3.5 -4.5 m and the snow fences should be erected on the windward side of obstacles that create snowdrifts. The minimum distance from fence to road should not be less than 15H; in certain circumstances in coastal climate, this can be reduced to 10H.

Lateral coefficient of friction for characterizing winter road conditions

2016 ◽  
Vol 43 (1) ◽  
pp. 73-83 ◽  
Author(s):  
Sahar Salimi ◽  
Somayeh Nassiri ◽  
Alireza Bayat ◽  
Don Halliday
Keyword(s):  
Field Experiments ◽  
Surface Friction ◽  
Concrete Surface ◽  
Snow Accumulation ◽  
Frictional Heat ◽  
Vehicle Speed ◽  
Test Road ◽  
Winter Road ◽  
Friction Measurements ◽  
The University

Real Time Traction Tool (RT3)-Curve was used in this study to evaluate the effect of ice and snow on tire–road lateral friction coefficient, herein referred to as the Halliday Friction Number (HFN). The field experiments for the study were performed in winter 2012–2013 on the University of Alberta’s test road facility in Edmonton, Alberta. Each run was repeated at three target speeds under varied road conditions, bare dry, dry with ice patches, ice, and three levels of snow accumulation. No considerable correlation was found between vehicle speed and the friction measurements for bare dry, ice- and snow-covered conditions. Expectedly, the bare dry asphalt concrete surface had the highest HFN, the presence of ice reduced the dry surface friction by 55%. The accumulation of snow on the dry surface reduced the HFN further than ice, by 69, 75, and 81% for light, moderate, and heavy snow, respectively. A falling trend was observed for friction as more snow accumulated on the ground. Analysis of the effect of number of truck passes over ice at −3.5 and −5 °C showed that ice can become more slippery after each pass of traffic. A similar analysis for snow revealed that more passes over moderate snow will compact the fresh snow into a slippery surface. For light snow, even at low temperatures (<−10 °C), passes of traffic will melt the snow through frictional heat and result in higher friction values.

scholarly journals The importance of wind-blown snow redistribution to snow accumulation on Bellingshausen Sea ice

2011 ◽  
Vol 52 (57) ◽  
pp. 271-278 ◽  
Author(s):  
Katherine C. Leonard ◽  
Ted Maksym
Keyword(s):  
Sea Ice ◽  
Mass Balance ◽  
Snow Accumulation ◽  
Blowing Snow ◽  
Wind Speeds ◽  
Antarctic Sea Ice ◽  
Drifting Snow ◽  
Bellingshausen Sea ◽  
Ice Mass Balance ◽  
High Winds

AbstractSnow distribution is a dominating factor in sea-ice mass balance in the Bellingshausen Sea, Antarctica, through its roles in insulating the ice and contributing to snow-ice production. the wind has long been qualitatively recognized to influence the distribution of snow accumulation on sea ice, but the relative importance of drifting and blowing snow has not been quantified over Antarctic sea ice prior to this study. the presence and magnitude of drifting snow were monitored continuously along with wind speeds at two sites on an ice floe in the Bellingshausen Sea during the October 2007 Sea Ice Mass Balance in the Antarctic (SIMBA) experiment. Contemporaneous precipitation measurements collected on board the RVIB Nathaniel B. Palmer and accumulation measurements by automated ice mass-balance buoys (IMBs) allow us to document the proportion of snowfall that accumulated on level ice surfaces in the presence of high winds and blowing-snow conditions. Accumulation on the sea ice during the experiment averaged <0.01 m w.e. at both IMB sites, during a period when European Centre for Medium-Range Weather Forecasts analyses predicted >0.03 m w.e. of precipitation on the ice floe. Accumulation changes on the ice floe were clearly associated with drifting snow and high winds. Drifting-snow transport during the SIMBA experiment was supply-limited. Using these results to inform a preliminary study using a blowing-snow model, we show that over the entire Southern Ocean approximately half of the precipitation over sea ice could be lost to leads.

scholarly journals The effect of wind direction on drift control by snow fences

2001 ◽  
Vol 32 ◽  
pp. 159-162 ◽  
Author(s):  
Yukari Takeuchi ◽  
Shun’ichi Kobayashi ◽  
Takeshi Sato ◽  
Kaoru Izumi ◽  
Kenji Kosugi ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
Wind Velocity ◽  
Wind Direction ◽  
The Other ◽  
First Case ◽  
Snow Fence ◽  
Snow Fences ◽  
Set Up ◽  
Cold Wind ◽  
Drift Control

AbstractSnowdrifting processes and the wind-velocity profiles around a collector and a blower snow fence were investigated in a cold wind tunnel. The purpose was to ascertain the effect of wind direction on drift control by snow fences. Three different cases were studied for both types of snow fence, and the resultant snowdrifts were compared. In the first case, the snow fence was perpendicular to the wind direction. In the second and third cases, it was tilted by 30° and 45°. When the collector snow fence was tilted, the amounts of snowdrift were much less than when the fence was perpendicular to the wind direction, because the area with low wind velocity was reduced to half behind the tilted fence. On the other hand, the blowing effect of the blower snow fence increased when it was set up at an angle to the wind direction. It is necessary to investigate the position where the blown snow is deposited by the tilted blower snow fence.

scholarly journals Numerical simulation of drifting snow: erosion and deposition models

1998 ◽  
Vol 26 ◽  
pp. 191-196 ◽  
Author(s):  
Mohamed Naaim ◽  
Florence Naaim-Bouvet ◽  
Hugo Martinez
Keyword(s):  
Mass Exchange ◽  
Field Measurements ◽  
Numerical Results ◽  
Back Reaction ◽  
Erosion And Deposition ◽  
Deposition Model ◽  
Drifting Snow ◽  
Snow Fence ◽  
Flow Turbulence ◽  
Deposition Models

Earlier works on numerical modelling are analysed. Anderson and Haff (1991) proposed a model using the “splash” function which was defined for cohesionless sand. The Uematsu and others (1989, 1991) and Liston and others (1993,1994) approaches are based on fluid-mechanics conservation laws where the snow is transported and diffused by the air flow. These models consider the saltation layer as a boundary condition.For the flow, and for the suspension, we adopt the same model as that of Uematsu and Liston. For mass exchange between the flow and snow surface, we have developed an erosion–deposition model where mass exchange is defined in relation to flow turbulence, threshold-friction velocity and snow concentration. Our snow-erosion model was calibrated using Takeuchi's(1980) field measurements. The deposition model was tested by comparing numerical results with wind-tunnel ones, for sawdust-accumulation windward and leeward of a solid snow fence with a bottom gap. The numerical results obtained are close to the experimental results. The main results of the various sensitivity experiments are: the leeward accumulation is very sensitive to the ratio (u*/u*t) (it appears for (u*/u*t) close to 1 and disappears for (u*/u*t) &gt; 1.2), the global accumulation produced by the fence increases as (u*/u*t) decreases and the back reaction of particles on turbulence extends slightly the windward accumulation.

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