Hazards

The main dangers associated with mountaineering are:

• falling rocks
• falling ice
• snow-avalanches
• falls from difficult rocks
• falls from ice slopes
• falls down snow slopes
• falls into crevasses
• weather

To select and follow a route avoiding these dangers is to exercise the climber's craft.

Falling Rocks

Every rock mountain is falling apart due to erosion, the process being especially rapid above the snow-line. Rock faces are constantly swept by falling stones, which are generally possible to dodge.

Falling rocks tend to form furrows in a mountain face, and these furrows (couloirs) have to be ascended with caution, their sides often being safe when the middle is stoneswept. Rocks fall more frequently on some days than on others, according to the recent weather. Ice formed during the night may temporarily bind rocks to the face but warmth of the day or direct sun exposure may easily dislodge these rocks.

The direction of the dip of rock strata often determines whether a particular face is safe or dangerous; the character of the rock must also be considered. Where stones fall frequently debris will be found below, whilst on snow slopes falling stones cut furrows visible from a great distance. In planning an ascent of a new peak, mountaineers must look for such traces.

When falling stones are mixed in considerable quantity with slushy snow or water, a mud avalanche is formed (common in the Himalaya). It is vital to avoid camping in their possible line of fall.

Falling Ice

The places where ice may fall may always be determined beforehand. Ice falls in the broken parts of glaciers (seracs) and from overhanging cornices formed on the crests of narrow ridges.

Large icicles are often formed on steep rockfaces, and these fall frequently in fine weather following cold and stormy days. They have to be avoided like falling stones.

Seracs are slow in formation, and slow in arriving (by glacier motion) at a condition of unstable equilibrium. They generally fall in or just after the hottest part of the day, and their debris seldom goes far. A skilful and experienced climber will usually devise a safe route through a most intricate ice-fall, but such places should be avoided in the afternoon of a hot day.

Hanging glaciers (that is, glaciers perched on steep slopes) often discharge themselves over steep rock-faces, the snout breaking off at intervals. They can always be detected by their debris below. Their track should be avoided.

Snow Avalanches

The avalanche is the most underestimated danger in the mountains. People generally think that they will be able to recognise the hazards and survive being caught. However, the truth is a somewhat different story.

120 - 150 people die in small avalanches every year in the Alps alone. The vast majority are reasonably experienced male skiers aged 20-35 but also include ski instructors and guides.

There is always a great deal of pressure to risk a snow crossing...