Sunday, 11 September 2022

THUNDERSTORMS IN THE DRAKENSBERG MOUNTAINS


When you see lightning, it has already missed you. When you hear thunder, relax, the show is over. The noise is just the audience rushing for the exits.”
Ira Wolfert





THUNDERSTORMS IN THE DRAKENSBERG MOUNTAINS






The Dragon of the Dragon Mountains comes out of his lair and roars defiance with Fire and Fury…”



   One of the most dramatic and awe-inspiring displays of nature is the sky-splitting spear of light that flashes from the thunder cloud during a storm and the deafening roar that follows it. It is not surprising that our ancestors were unable to explain lightning, and consigned it to the world of the supernatural. Today, we know that lightning is no more than a gigantic spark, and our scientists have been able to explain exactly what brings it about.

   When a thunder cloud is being formed, a mass of warm, humid air rises until it cools and condenses into water vapor and tiny ice crystals. In due course, as the clouds grow in size, these droplets and crystals coalesce to form raindrops and hail. When this happens, a separation of electric charges takes place within the cloud by a complicated process that need not detain us here. What is important is that the cloud mass now becomes a huge dynamo, generating millions of volts of electricity. It acts, too, as a huge storage battery, with the positive terminal at the top of the cloud, and the negative terminal at the bottom – perhaps several kilometers below.

   Meanwhile, the base of the cloud which carries an overall negative charge induces a positive charge on the surface of the earth directly below. As the cloud drift over the countryside, the positive charge on the ground follows the negative charge like shadow, climbing trees, ridges, pinnacles – anything that will bring it closer to the cloud.

   We must now note that when a negatively charged object is brought into contact with one that has a positive charge, electrons flow from one to the other so that the two objects become equalized, and the tension between them neutralized. If, however, the current is high enough, they do not even need to touch – the electrons will leap across the space separating them, making a spark. Lightning is nothing more than spark on a gigantic scale. It is in fact, the high current discharge which cancels the electrical imbalance within the storm cloud itself, or between the cloud and the earth. The potential difference in energy between the cloud and the ground can be as much as a thousand-million volts of electricity! It is estimated that there are about 1 800 storms in operation throughout the world at any one time, and that lightning strikes the earth about 100 times every second.

   When lightning flashes, we do not see the electrons themselves. What we see is the air particles in the strike path which have been super-heated to incandescence. The particles are made white-hot by the lightning current, and reach temperatures as high as 30 000 degrees centigrade. The super-heated air expands explosively, producing a shock-wave, which breaks the sound barrier and we hear thunder.





   The long drawn-out peal that issues from a single stroke of lightning may last for several seconds. There are several reasons for this. In the first place, sound travels at about 330 meters per second, or about one kilometer in 3 seconds – far slower than the speed of light. If lightning strikes nearby, the first acoustic signal to reach our ears (usually a deafening crash) will come from the end of the stroke, perhaps only a short distance away. Sound, however, will be generated along the entire length of the lightning path, which might extend several kilometers into the sky. This means that thunder will be heard continuously until the sound waves from the furthest point of the strike channel have reached us. The sound we hear is uneven because lightning normally takes an uneven path. This brings about the rolling and rumbling effects which last for many seconds. Reflections, or echoes, from mountains or valleys may accentuate these sound effects, and cause them to continue even longer. This is one of the reasons why storms in mountain regions are so dramatic.

   Incidentally, with our knowledge of the speed of sound, we can easily determine the approximate distance of a lightning strike. All we have to do is count the number of seconds it takes for the peal of thunder to reach us after the flash appeared, and divide the time in seconds by three. This will give the distance in kilometers between us and the point of impact.

   Every year, people in Kwa-Zulu Natal are killed by lightning. Most of these are people living in grass huts, but lightning fatalities are not unknown in the Drakensberg. Many years ago, a man and a girl (daughter of the Administrator of the Free State) were killed on the escarpment close to the Namahadi pass near the Chain Ladder in the Royal Natal National Park. A brass plaque, commemorating their deaths, use to stand at the spot – a solemn reminder to all passers-by of the perils of a summer storm. A game ranger, John Clarke and his girlfriend, Carol Richter, together with their dog, were killed by lightning during a “dry storm” on the 20th December 1979. They were standing on a ledge overlooking the Injasuthi Valley at the time, watching the storm built up.






    Lightning generally follows the shortest possible route between a cloud and the earth. For this reason we should avoid tall trees, rocky outcrops, and high summits, particularly if they are well defined. There is, however some evidence to prove that a tall pinnacle or rock projection can act as a lightning conductor, and provide a zone of protection for the hiker. The area protected by the high point is termed the lightning shadow, and its area has a diameter four times the height of the projection.

   If the hiker finds himself in an exposed position during a thunder storm, he should avoid running for shelter at all cost. Running in a potentially charged area creates a magnetic field which attracts lightning. He should crouch down on some kind of insulating material, such as a sleeping bag or pile of clothing. Standing or lying down can be dangerous. You should keep out of vertical cracks and chimneys flowing with water, and away from dripping overhangs. Water is a good conductor of lightning, and hikers have received severe shocks even hundreds of meters below a summit after a strike. Rock climbers should remember that a wet abseil rope will provide a good path for an electrical current, while belay ropes can direct a stream of water on to the body.

   Perhaps the very best advice is, keep calm – never give way to panic. If you have taken reasonable safeguards and precautions, your chances of being hit by lightning are very slim. Enjoy the show!!

   Sunrise from the summit of the Berg is never more beautiful than after a night of storms. The air is clean and bracing, and the silence is undisturbed. The light breaks through the parting clouds in a blaze of glory, and lays a mantle of gold over the rain-washed peaks. This is the moment to be awake and alert, for the beauty of daybreak never lingers.



If you are in the mountains, you need to assess your situation and decide what to do. Here are some guidelines:

   If you’re above the tree line on an exposed ridge, get lower. Don’t hide under trees.
   If you’re in a forest and can’t find a clearing, find the lowest group of trees you can and try to stay away from their bases.
   If you can, look for a cave, or find a low, open space, a meadow or a clearing of some kind, and head to the lowest ground possible.  The entrance to a cave can be hazardous, so move in and out as quickly as possible.
   Stay away from taller rocks. Rocks can attract lightning the same as anything; if there’s an appealing shelter under a rock; make sure it’s not very tall.
   If you’re in an open space, spread out about 20 feet apart from each other and away from tall trees, and try to stay dry and warm. Wait for the storm to clear, or until you haven’t had lightning closer to you than 10 seconds (mark the time from when you see the flash to when you hear the thunder) for ten minutes, and then get to safety.
   Once you’ve found your place of refuge, whether in a group of shorter trees, the back of a cave, a low spot in a meadow, or a low spot on a talus slope, get into the lightning position. Minimize your contact with the ground by standing on a foam pad with your feet close together and crouch or squat to lower your overall height. If you don’t have a foam pad, you can use your pack. Make sure to keep your shoes on, as the sole will help insulate you. The idea is to minimize your contact with the ground and stay insulated from the ground.
   If you’re at your camp, evaluate how close a proper shelter is. If a building or your car is nearby, then head for it.  Otherwise, evaluate the safety of your camp spot. Are you near tall trees? Are you on a highpoint in a clearing? If your tent is not near tall trees, and you’re in a low spot in a clearing, you’re probably best staying in it. Remove all the metal items you can and put them far away from your tent. Try to stay insulated from the ground using your sleeping pads and backpacks. The exception would be if you have an old tent with steel or non-anodized aluminum poles, as these will conduct electricity. If your tent has anodized aluminum poles or fiberglass poles and you’re pitched in a good spot, staying in your tent may be your best option.
   If you’re climbing, you’re in a tough spot. The best option is to go down. If this isn’t possible and you have to wait it out on the wall, try to find a good ledge or a cave you can take shelter on or hide in. Space out as best you can from your climbing partners. If you get stuck at a hanging belay, have some people lower down so your group is as spaced out as possible. Bolts and chains will attract/conduct electricity, but your anodized aluminum carabineers won’t (provided the coating isn’t worn off). It’s important to remember, however, that everything conducts electricity when it’s wet.
   If someone gets struck by lightning, there are three major risks: electrical shock, secondary heat production, and explosive force. Electrical shock and skin burns are the most common injuries sustained after a lightning strike. Send for help immediately, treat for shock right away, make sure the victim is breathing and has a strong pulse, administer chest compressions and rescue breathing if necessary, and then treat any burns. Make sure to minimize additional lightning risk while treating victims. 


   Remember: the easiest and most effective way to stay safe in a lightning/thunderstorm is not to get caught in one. Be alert to signs in the weather that will tell you a thunderstorm is coming. If you do get caught, assess your situation. How far are you from safety? How severe is the storm? Can you go down? Should you stay put? In high alpine terrain, speed is safety. Early starts help you get off the mountain or out of the danger zone before a storm hits. Having a good base of fitness, whether hiking, climbing, or paddling, will help you be able to step on the gas and get out of a bad spot if a storm moves in on your fun.
   Do NOT seek shelter under a picnic shelter, lone tree, or other object to keep you dry. It will attract lightning. The rain won't kill you so it is better to be wet and alive than dry and dead.

   Come down from high places. Seek a valley or depression in the terrain. Be careful of entering a dry wash that may channel a flashflood from the rainstorm.
Seek shelter in a low stand of trees. This will help keep you dry and not attract lightning.

   If you are above tree line, seek shelter in the lowest area you can reach, preferably with large boulders around so you can get some protection from driving rain behind some smaller boulders.

   Put on your raingear and remove your backpack.

   If you have a metal frame pack, leave it 100 feet from where you are seeking shelter.

 If you have a hiking stick or poles, leave them with your pack.

   Your group should not huddle together. Instead, have each person find shelter about 100 feet apart. This minimizes the possibility of multiple casualties from a single strike.

   If you are not able to get to any shelter, you need to become a small target and cross your fingers. Minimize your contact with the ground and minimize your height. 

Crouching down on the balls of your feet placed close together with your head tucked down is the recommended position. This position reduces your exposure and encourages any lightning strike to travel down your back and hopefully have less damage to vital organs. Lightning travels through the ground from the point of impact in random tendrils similar to tree roots. The smaller your footprint, the less chance there is of you being shocked from a nearby strike.

Cover your ears and close your eyes to protect from the intense noise and light of nearby strikes.



Lightning First Aid


  • ·        Lightning is an extreme electric shock and has similar first aid requirements for burns and heart attacks.

  • ·        Immediately after a close strike, do a headcount of everyone in your party having them call back to you that they are ok. If someone does not respond, go to their location. 

  •      Only allow those you need to gather. Keep everyone else spread out since there is still danger of additional strikes.

  • ·        There is no electrical residue after a strike. It is safe to touch someone that has been struck.

  • ·        If there are multiple victims, prioritize care needed. A victim that is not breathing is highest priority. There is a relatively good chance of reviving a lightning victim with CPR.

  • ·        Check for and give first aid for burns. Check around jewelry, buckles, and fingers and toes especially.

  • ·        Treat for shock, keeping the victim warm and calm.
  • ·        Immediately send for help.

We as hikers, explorers, and adventurers have the absolute duty to respect and protect our Wildernesses. Nobody else will do it for us. Take ownership!

 

 

The End.

 

Safe Hiking.




 









References and Acknowledgements

Photos - “A Camera in Quathlamba” – ML Pearce
Compiled by W Pelser





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