Avalanche information help!?

Question

i need help on Avalanches. 1. i need a description 2. i need the location of where these might occur in new zealand 3. the importance (why this hazard is important) 4. Effects on man, outline two effects in detail 5. Man's Influence: what does man try to do to reduce the effects of this hazard.. Please help

dam it people!! plz dont just copy and paste from wikipedia! gees

Answer 1

1) A fast moving mass of snow. Results from a slope being overloaded - a greater mass of snow than the bond between layers can support. Most likely if the previous surface become hard and slick through effect of sun and wind. But can be due to a weak layer when temperature-gradient driven vapor migration has weakened a particular depth.

2)Any slopes that get snow that are between 30 and 60 degrees of slope. (shallower doesn't slide and steeper doesn't build up now). Most fatal ones are between 40-50 degrees.

3) roadway hazard and damage, destroys structure/building in alpine settings, kills people, increases costs and disallows certain landuses.

4a) suffocation - trapped under the dense, distrubed snow, one can't make any air space tp breath from, even if conscious. If a party can't self-rescue, getting word out is only for body recovery. Saves happen within 30 minutes, rarely longer.

4b) Destruction of houses - leaves little behind - just busted up materials. happens in Alaska (google Juneau) and Switzerland with some regularity.

5) the clever ones don't build in historic avalanche paths. Ski areas and some highway departments drop bombs from helicopters or shoot 105mm howitzer shells into unstable snow banks to cause them to fail before people get on them. Some people carry avalanche beacon (transceivers to locate buried companions). Dogs are used at some ski areas and in the Alps for rescue and body recovery, some roads are placed within tunnels, some towns have uphill barriers to re-direct snow flow.

That enough?

Answer 2

An avalanche is a slide of a large snow (or rock) down a mountainside, caused when a buildup of snow is released down a slope, and is one of the major dangers faced in the mountains in winter. An avalanche is an example of a gravity current consisting of granular material.

In an avalanche, lots of material or mixtures of different types of material fall or slide rapidly under the force of gravity. Avalanches are often classified by what they are made of, for example snow, ice, rock or soil avalanches. A mixture of these would be called a debris avalanche.

A large avalanche can run for many miles, and can create massive destruction of the lower forest and anything else in its path. For example, in Montroc, France, in 1999 300,000 cubic metres of snow slid on a 30 degree slope, achieving a speed of 100 km/h (60 mph). It killed 12 people in their chalets under 100,000 tons of snow, 5 meters (15 feet) deep. The Mayor of Chamonix was convicted of second-degree murder for not evacuating the area, but received a suspended sentence. [1]

During World War I, over 60,000 soldiers died as a result of avalanches during the mountain campaign in the Alps, many of which were caused by artillery fire. However, it is very doubtful avalanches were used as deliberate weapons; more likely they were simply a side benefit to shelling enemy troops, occasionally adding to the toll taken by the artillery. Avalanche prediction is difficult even with detailed weather reports and core samples from the snowpack. It would be almost impossible to predict avalanche conditions many miles behind enemy lines, making it impossible to intentionally target a slope at risk for avalanches. Also, high priority targets received continual shelling and would be unable to build up enough unstable snow to form devastating avalanches, effectively imitating the avalanche prevention programs at ski resorts.

Answer 3

HI,

for NZ ppl, there is separate website reg to Avalanches info.

http://www.avalanche.net.nz/