by Jon E. Lewis
Choose lightweight, loose and comfortable clothes. The looseness provides insulation and prevents excessive evaporation of sweat. Sandals are common favourites for footwear, but beware of thorns, snakes and scorpions. If you expect the going to be rocky or difficult military pattern or lightweight desert boots are best.
SURVIVING THE DESERT – A CHECKLIST
Survival in a desert as in any area depends upon your knowledge of the terrain and the basic climatic elements, your ability to cope with them, and your will to live. Every year the desert continues to kill the unwary, the unprepared and the foolish.
Types of terrain
Each type of terrain seemingly blends into another. There are five different types; mountainous, rocky plateau, sand dune, salt marsh and highly dissected rocky terrain called “gebel”.
Sand dunes: these are usually extensive areas covered with sand and gravel. Some dunes may be over 300 metres high and 10 to 15 miles long; others will be completely flat. They can be devoid of plant life or covered in scrub up to two metres in height. Any form of travel through sand dune deserts should be avoided.
Salt lakes: If a large volume of water enters a basin, a lake may develop. However, the water has a very high salt content and is undrinkable.
Salt marshes: This type of terrain has a highly corrosive effect on boots, clothing and skin.
Rocky plateau deserts: These are characterized by many solid or broken rocks at or near the surface, and there may be sand dunes around the plateau. Rock outcrops may offer cover and shade. The rocks often form natural cisterns which collect water after rains.
Mountain deserts: High altitude deserts have thin air and little or no vegetation. Sunburn is a real danger, and movement at altitude requires extra physical exertion.
TEMPERATURE CONVERSION
Most of the world’s military use the Celcius scale, but some readers may be more familiar with Fahrenheit. Here are some approximate conversions.
50°C
120°F
30°C
90°F
20°C
70°F
10°C
50°F
0°C
32°F
−10°C
15°F
−20°C
−5°F
−30°C
−20°F
CLIMATIC ELEMENTS
Temperature variation: The temperature may vary from as much as 55°C during the day down to 10°C at night; warm clothes are essential. Obviously, work or travel at night requires less water than day but may be more hazardous.
Rainfall: It does rain in the desert on high ground and, when it does rainwater runs off very quickly in the form of flash floods. The floods excavate deep gullies and ravines know as “wadis”. Vegetation may appear after rain, but the water evaporates leaving the lands as barren as before.
The burning sand: The temperature of the desert sand and rock averages 15 to 20 degrees more than that of the air, so if the air temperature is 45°C then the sand would be around 60°C. You will be unable to walk around without adequate foot protection.
Your ability to cope
Convoy: Never attempt to cross a desert area in a single vehicle; always travel in convoy.
Movement by night: In most deserts, moving by night is so hazardous as to not be a viable option.
An individual first aid kit depends on personal choice and allergies. Seek your doctor’s advice if you have any doubt about personal medications. You may also need a prescription for some of the items suggested. Your kit may contain some or all of the following:
Butterfly sutures
Surgical blade
Plasters – assorted sizes and waterproof
Potassium permanganate as general disinfectant
Mild painkillers for toothache, headaches e.g. Codeine phosphate
Intestinal sedative e.g. Immodium
Antibiotic cream and tablets
Antihistamine for bites, stings, irritant rashes, e.g. Piriton
Water sterilising tablets e.g. Puritabs
Anti-malaria tablets e.g. Paludrine, Daraprim, Mepachrin
Equipment: Radios and other sensitive items of equipment are likely to fail when exposed to direct sunlight in the desert.
Dehydration: Keep activity to a minimum during the day to minimize water loss. Take sips of water often rather than normal drinking or gulping.
Animals and birds: Water sources are often indicated by animal trails and droppings or birds in flight.
DEHYDRATION
The body absorbs heat from direct sunlight and from the atmosphere. You will also absorb heat reflected from the ground or from direct contact with the ground. Any increase in body temperature of three or four degrees C (six to eight degrees F) above normal (98.6°F/37°C) for any extended period can cause coma and death.
Your body attempts to dispose of this excess heat by sweating, which can lead to loss of body fluids and dehydration.
Drink early in the morning while temperatures are low. Remember, it is the water in your body that keeps you alive, not the water in your waterbottle. Don’t ration your water intake to little sips. That will not prevent dehydration. If you drink only enough to satisfy your thirst you can still suffer from dehydration. Your water intake must remain sufficient to make you urinate three times daily. Healthy urine is a pale straw colour.
In summer in the Sahara, you will need to drink up to 6 litres/10 pints of fluid daily. Keep your clothing on, as the insulating effect of a layer of clothes will reduce evaporation of sweat and reflect direct sunlight.
If you lie up during the heat of the day, remember that ground temperatures may be as much as 15°C hotter than the air temperature. Break through the crust of the desert into soft sand and you will find the temperature is as much as 30° cooler at 45cm deep. So try to rest in deep shade or about 45cms above or below ground level. Bushmen of the Kalahari Desert urinate into holes in the ground and lie in them in the heat of the day to reduce sweating.
Don’t smoke or breathe through an open mouth. This exposes the mucous membrane to the dry atmosphere, increasing your rate of dehydration. Reduce conversation for the same reason.
Finding water
If you are near a water supply stay there and set up ground-to-air distress signals. If you have to keep moving, look for signs that indicate the direction of a water supply.
Don’t rely entirely on wild animals as a guide to water in the Sahara. Some are so adapted that they do not need a regular water intake as we do. Dorcas gazelles, jerboas and gerbils, for example, extract all the moisture they need from their foodstuffs. Foxes, jackals and hyenas, however do not stray too far from water.
Listen for the sounds of birds and baboons at early morning or evening. Quail fly towards water in the evening and away from it in the morning. Doves use the water both morning and evening but it may be a long way off. Some turtle doves will fly 50–75 kilometres to water.
BUILDING A DESERT SHELTER
This shelter reduces the midday heat by as much as 15 to 20 degrees. However it does take more time and effort to build than other shelters so build it during the cool night to prevent increased dehydration during the day.
Construction
1 Find a low spot or depression between the dunes or dig a trench 45 to 60 cms deep and long and wide enough for you to lie down in.
2 Pile the sand from the trench around three sides to form a mound.
3 On the open end of the trench, dig out more so that you can get in and out easily.
4 Cover the trench with material such as a parachute or poncho.
5 Secure the cover in place using sand or rocks as weights.
You can reduce the temperature of the shelter further by adding an extra layer 30 to 45 cms above the first, creating an airspace between the two layers as shown.
Man, on foot, and camels will eventually lead to water – but remember that a camel can walk vast distances between water stops. In camels, the water is stored
in the stomach and Arabs in dire straits have been known to kill the animal and use this store of water.
SURVIVAL KIT
This could be combined with the first aid kit in a single pouch in the pack or on the belt. It is not to be treated as a kit to be opened only in an emergency. Use and familiarize yourself with the contents of your kits. Don’t wait until you get into trouble before practising your survival techniques.
Wire saw with loop handles
Second compass (button or lapel type)
Fish hooks, line, weights and swivels
Strong needle and thread
Waxed non-safety matches that will strike on rough surfaces
Single large candle or three birthday-cake candles
Flint and steel
Cotton wool packing for use as fire starting aid.
Table salt in small container
Signal flares
Pen torch
Tube of Dextrose tablets
Heliograph
Ground to air recognition tables and Morse code sheet
Marker panel in fluorescent material
Whistle
Condom for water carrying
Don’t make the mistake of thinking that tyre tracks will lead to water – you could mistakenly follow your own tracks or those of someone else who is equally lost. In some parts of the Sahara the “main” road is as much as 15 kilometres wide.
Study the rock in your surroundings; sandstone will absorb water after a rainstrom, basalt-type rocks will pool it on the surface. Dry stream beds, known as wadis, sometimes have water below the surface. Finding it is the problem. Look for greenery on the outside of a bend in a water course, and dig at its lowest point. You may have to dig deeper than your own height.
If you do find water, think before you camp in the wadi itself. If it rains, wadis fill up with remarkable speed and become raging torrents.
Remember, survival in the desert is a matter of knowledge of the terrain, and minimising risks. As with all other extreme environments, you should not expose yourself to danger without proper training. The heat and the sun are your enemies; water and shelter are your friends. Without water you will be dead within a day; and if you can’t find shelter, wear loose clothing. Try to avoid exposing yourself to the sun; you don’t see desert nomads working on their tans!
The desert still
The first attempts to extract moisture from air pockets within the desert sand were carried out simultaneously and independently at opposite ends of the world. Today, we accept the desert survival still as being a normal aid to survival in any desert.
To make a still, dig a hole roughly one metre square and 70 cms deep. Put a container at the bottom of the hole. Then put the end of a drinking tube at the bottom of the container. Cover the hole with a polythene sheet about 2m square threading the drinking tube under the edge of the sheeting. Then seal it all round the edge of the hole with sand or stones.
Let the sheet “belly in” – you can help by placing a stone in the centre of the sheet. This creates an inverted cone over the container at the bottom of the pit. The polythene must not touch the sides of the pit, or the container itself. If it does the condensed fluid will be wasted.
Theoretically, the sun’s rays heat the ground inside the hole and cause the moisture trapped inside to evaporate. The moisture then saturates the confined air space and condenses on the cooler surface of the plastic sheet. This runs down into the container, where you can drink it through the drinking tube without having to destroy the still.
A still like this can produce up to a litre of water a day in some parts of the desert. In other areas very little is produced at all, unless you add greenery or urine in the evaporation space under the plastic sheet.
PROPRIETARY CHEMICAL PURIFIERS
Chloromine T: 1 cm/3/8th inch of matchstick loaded for 22 litre/5 gallon can
Tincture of iodine: 3 drops per litre of water
Household bleach: (5.2% sodium hypochlorite) 2 drops per litre for clear water, 4 drops for cloudy water. Water will taste of chlorine.
Puritab: 1 small tablet for 1 litre bottle. 1 large tablet for 5 gallon can.
Potassium permanganate: enough to colour the water pink.
The penalty you will pay for not purifying your water properly or neglecting to prepare food carefully or for lack of hygiene generally, is a severely upset stomach. This in turn can lead to dehydration and heat illness through loss of body fluids. Treat an upset stomach with a proprietary preparation, or if you don’t have one, use crushed charcoal or burnt crushed bone. Neither taste very pleasant but both are effective. The tannic acid in a very strong brew of tea will also help. Continue to drink plenty of fluids during treatment.
Purifying water
Treat all water in the desert, no matter where from, as suspect. Filter dirty water through several layers of cloth or a Millbank bag to remove solids. Even radioactive fallout can be removed in this manner.
Purifying the water involves killing the germs. To do this use purifying agents such as Puritabs, Halzone, Chloromine T, iodine, permanganate of potash, or simply boil it for between three and five minutes.
Add charcoal while the water is boiling to remove disagreeable colours. Agitate it to restore its taste, or add a small pinch of salt.
There are many chemical purifiers, and the choice is a matter of personal taste. Generally, the water needs to stand for up to 30 minutes to allow the chemical time to act properly.
Carrying water
If you have any control over your circumstances, think about how you will carry your water supply. Always take 25 per cent more than you think you need, in several containers of unbreakable material. Glass and thin plastic containers are non-starters. Conventional military water bottles in tough plastic or aluminum are reliable, as are some of the civilian versions.
Avoid carrying single one or two gallon containers. Desert terrains are unforgiving – a slip can result in all your water supply being lost.
A condom from your survival kit (carried inside a sock for additional support) makes an excellent portable container.
DESERT HAZARDS
Many of the creatures that live in the desert are potentially dangerous, from bats and snakes to scorpions and centipedes – and even dogs and spiders. Heat exhaustion, malaria and storms all offer their own hazards as well.
BITES
On your own in the desert, avoid suspect animals at all times.
Rabies virus is carried in the saliva of an infected animal and enters your body through breaks in the skin. Even a lick from a friendly but infected animal can infect you through a cut or abrasion. Potential carriers include dogs, cats, bats, and some types of rodents.
If you are bitten by any animal get a tetanus booster as soon as possible.
Scorpion stings
There are two common types of potentially lethal scorpion in the Sahara; Androctonus australis and Buthus occiutanus (also known as Fat Tailed scorpion because of its massive tail), which is often cited as the world’s most dangerous. Drop for drop, their venom is as toxic as that of a cobra and can kill a man in four hours. If the scorpion stings in self-defence it will usually inject the maximum dose of poison.
The sting of a buthin scorpion produces intense pain at the site of the sting, often without discolouration apart from a small area of gooseflesh. A feeling of tightness then develops in the throat, so that the victim tries to clear imaginary phlegm. The tongue feels thick, and speech becomes difficult. The casualty becomes restless, with involuntary twitching of the muscles.
Sneezing bouts and a runny nose follow. There is an uncontrolled flow of saliva, which may become frothy. The heart rate will increase, followed by convulsions. The extremities turn blue before the casualty dies. The whole sequence of events may take as little as 45 minutes or as long as 12 hours.
Snakes
Snakes are permanent residents in most parts of the desert. They hibernate, however, and so you’ll see fewer snakes in
winter.
Most are venomous, so regard any snake bite as suspect and treat it as promptly as possible. Simple precautions against snake bite include shaking out boots and sleeping bags before you use them, and using a torch after dark.
Don’t go barefoot; certain types of snake actually bury themselves in the sand, leaving only their nostrils and eyes showing. They ambush their prey – including you – in this fashion and are extremely difficult to spot.
If you get bitten by a snake, study the pattern of teeth punctures. If there are two well-defined punctures, the bite will be that of one of the viper group. Non-poisonous snakes with solid fangs, and mildly venomous back-fanged snakes, make a horseshoe shaped row of teeth marks.
It takes only 5 mg of venom from the Saw Scale Viper to kill a man. As with scorpion stings, defensive bites tend to contain the maximum amount of venom.
However, not every snake bite is fatal. You’re more likely to survive a bite to the shin than one deep in the muscular tissues of the thigh or calf.
Treatment for snake bite
Ideally a snake bite casualty should be immobilized and given sedatives. Ice is put on the bite site, and a tourniquet applied and loosened at frequent intervals, and the casualty evacuated to hospital for treatment with anti-venene, adrenalin and plasma. The snake is killed for hospital identification.
In reality, you will probably be able only to attempt to restrict the amount and rate of venom entering the blood stream by applying a tourniquet between the bite and the heart. The tourniquet must not cut off the blood supply entirely – this can cause tissue damage and possibly gangrene and kidney failure. Release the pressure each half hour until you get help.
The patient must also be rested as much as possible, and kept calm. Panic can become a major problem – it increases the heart rate and so speeds the circulation of the venom in the blood. Physical exertion must also be avoided.