Tuesday, 2 January 2018

DRAKENSBERG MOUNTAINS - Rainfall and Thunderstorms





Quathlamba
A mass of Spears. Named thus by the Zulu warriors before the white man came. Today called the Drakensberg, Mountains of the Dragon. Evocative names, both equally applicable to South Africa’s mightiest mountain range with its spear-like peaks – reminiscent of the saw-toothed spine of a gigantic dragon.”

 


“Listen to the streams as they gurgle from their cradles and you will hear the story of the mountains. You will hear fascinating tales if only you listen! Lie next to a stream and listen to the song of the mountains. The smiling faces of the flowers, dancing in the wind. Venture into the remote valleys or stand on a peak at sunrise or sunset, after snow has fallen, and you will hear a song that you will never forget - the Song of the High Mountain".



DRAKENSBERG WILDERNESS PHOTOS © WILLEM PELSER







THE MOUNTAINS ARE MY BONES; THE RIVERS ARE MY VEINS,
THE FORESTS ARE MY THOUGHTS AND THE STARS ARE MY DREAMS,
THE WILDERNESS IS MY HEART, IT IS MY PULSE, 
THE SONGS OF THE WILDERNESS WRITE THE MUSIC OF MY SOUL.”
UNKNOWN












DRAKENSBERG MOUNTAINS Rainfall and Thunderstorms



The eastern escarpment is one of the highest rainfall areas in South Africa, some parts receiving more than 1 500mm p.a. This may be augmented by up to 30% by cloud and mist.





It was shown that there is a sharp increase of rainfall with height and a suggestion that above 2400m rainfall again decreases towards the summit. About 85% of the rain falls during summer months (October to March) and a high but undetermined proportion of this is a direct result of orographic (relief) effects and associated thunderstorms.


The top of the escarpment may expect to receive about 95 rain days per year while the area below probably receives significantly more. According to previous studies the Drakensberg receives 70-80% of possible sunshine hours during winter and 50-60% during summer.




Thunderstorms, which occur mainly in the middle to late afternoons during the summer months, are of particular importance to those walking or climbing in the Drakensberg as they may “brew up” very rapidly. Two types occur: those associated with a moisture discontinuity and moving across the country from a generally westerly direction and those which develop along the eastern edge of the escarpment. The former are often high above the ground while the latter are likely to engulf one in mist at very short notice – frequently a matter of 5-10 minutes. The need to be properly equipped and attired even for short walks is self-evident.


Lightning is an important cause of fires in the Drakensberg and it is said that it plays a part in landscape formation by the splitting and shattering of rocks and is possibly also the cause of the collapse of rock pinnacles in some areas. Hail, on the other hand, is infrequent and of little ecological significance.


Lightning in the Drakensberg may be severe and fatalities have occurred. It is difficult to give advice on this matter other than to find complete shelter such as a cave, overhang, brick building, or vehicle. If caught in the open the following precautions are widely accepted:

Avoid at all costs sheltering under isolated trees, especially of the deciduous or spreading variety. It is comparatively safe to shelter under groups of trees, giving preference to pines.

Keep away from high points and from telephone and fence posts. Dismount if riding a horse.

If no suitable shelter is available simply sit down and make yourself as comfortable as circumstances permit and try to convince yourself that the statistical probability of being struck is fairly remote!





Finally, despite the emphasis upon the influence of climate on humans, it is worth observing that birds and mammals too are subject to its effects. For the herbivores food is scares and of low nutritional value during winters, a situation aggravated by the fact that former migration routes to warmer areas with better grazing are no longer open. The survival chances of the weak or old are thus severely reduced. For the carnivores and raptors at or near the top of the food chain, winter is probably as great a trail.



The End.

Safe Hiking.



References and Acknowledgements

From the book – A field guide to the Natal Drakensberg – Irwin/Akhurst.

Photos:  ©Willem Pelser

Compiled by:  Willem Pelser










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