Читать книгу Walking and Trekking in the Sierra Nevada. 38 walks, scrambles and multi-day traverses онлайн

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Blizzards

A combination of snow and high winds can turn a relatively gentle outing on an accessible mountain into a life-and-death struggle. It’s important to remember and respect the high altitudes and the sometimes long distances involved in reaching safety. Local mountaineers don’t leave home in these conditions, but if you do happen to get caught out it will help if you’ve done your homework with regard to map, compass, escape routes etc. However, given today’s wealth of online weather resources, such problems should not occur.

Snow bridge collapse

This happens in the spring melt when rivers and streams carve tunnels beneath the valley snows. The unstable snows above look perfectly fine to walk on but can collapse, causing injury.

Water sources

In the spring, rivers and streams gush down the hillsides of the Sierra Nevada, swollen by the snowmelt waters, and there is no problem locating suitable drinking water. In fact water is not an issue until July, when these streams start to dry up and eventually disappear (although after ample snow years some patches of hard snow may remain throughout the summer on north-facing slopes, especially in the Corral del Veleta and on Mulhacén and Alcazaba). In late August, September and until the rains arrive, walkers may have to rely on the lakes for water, taking water from the lake itself if there is no flowing exit stream. The waters of the Sierra Nevada are normally very pure, but the best advice is to use a filter to remove any protozoa, bacteria or cryptosporidium.