• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Management of mass movements : Managing landslide hazards

Extracts from this document...

Introduction

Management of mass movements Managing landslide hazards 1. Modifying the event Slope stability can be increased by a variety of engineering techniques, which although expensive, enable control of land sliding to be largely successful. There are 2 key issues with this approach to landslide hazard management: cost and responsibility. Government funding may be available for emergency stabilization. However, building codes can enforce some user if these techniques by private developers. 2. Modify vulnerability Most mass movements are not very rapid and thus forecasting, warning and evacuation are possible techniques. Community preparedness can be used if people are aware of the early signs of mass movement such as bulging walls, tension cracks, tilted poles and fences and new areas of waterlogged ground. Hazard mapping is increasingly being used especially in MEDC's, as the factors that favour land sliding can be assessed to produce a hazard map. ...read more.

Middle

There are 3 main forms of snow avalanche with different characteristics of slope failure, flow and occurrence - loose snow, slab and slush. Slab avalanches are the most dangerous since large masses of snow are involved. Snow builds up in layers following each snowfall event. Initially the density is low, but as snow continues to be added the density in the lower layers increases as air is squeezed out to form firn. However, in some snow packs the snow becomes less dense in places as ice and snow crystal grow and the voids between them are enlarged. This forms a weak layer in the snow called a depth hoar. Thawing and freezing between different snowfalls produces boundaries which act as weaknesses within the snow pack. ...read more.

Conclusion

What techniques are used for modifying the hazard event? Avalanches can be managed through artificial avalanche creation. By creating a series of smaller avalanches at safe times, the hazard can be controlled as the snow pack is removed. This approach is expensive and uses explosives and military weapons. Modifying the vulnerability Warning systems are common for avalanche hazards and nearly 30 countries have systems in operation, which use both forecasts and prediction. Forecasts are used for day-to-day management of winter sports area, whereas predictions are used for hazard land zoning. Forecasting is not precise but involves regular snow stability tests and meteorological data. Avalanches triggers by storms are the easiest to forecast but snow pack changes are more difficult. In Switzerland avalanche hazard maps have existed since 1878. Three zones are used: high potential hazard, moderate, and no hazard. These are based on topographic maps, field observation, long term records, and run out distance. This approach needs much financial and time investment. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Hazardous Environments section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Hazardous Environments essays

  1. Marked by a teacher

    Explain the increasing frequency of Hydro-meteorological Hazards.

    3 star(s)

    which perhaps would not have been before, such equipment was introduced. This would make it able for more small-scale hazards to be reported, in the more isolated area which people may not be aware of. Another suggestion, linked with that of the increase in development of technology worldwide, is the

  2. With reference to a range of hazards, assess the success of prediction techniques in ...

    Scientists also study the rate in which the strain accumulates in the rock as well as unusual animal behaviour. Scientists study the past frequency of large earthquakes in order to determine the future likelihood of similar large shocks. For example, if a region has experienced four magnitude 7 or larger

  1. To what extent can hazards be controlled and managed?

    Coexistent to this plan, is one by which they could open up embankments further up the river allowing massive flood planes for controlled flooding, to flood that are less densely populated to relieve the lower course of the river, of discharge and sediment.

  2. Volcano Assessment.

    In some places, where they are pulling apart and making the sea floor spread, they are called divergence zones. In other places where they are shoving up against each other and crumpling the edges or driving one another down into the Earth's interior, they are called convergence zones.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work