GENERAL: The desert is harsh; living conditions can be extremely uncomfortable; the desert can easily kill an unprepared soldier. The desert can pose a constant challenge to every soldier, and each must be physically, mentally, and professionally prepared to meet this challenge. This newsletter describes characteristics of the desert, and its effects on personnel and equipment. Deserts are arid, barren regions of the earth, incapable of support abundant plant life due to the lack of fresh water. Temperatures vary according to latitude and season. Day to night temperatures can vary as much as 70 degrees F. Some plants and animals have successfully adapted to desert conditions where annual rainfall may vary from 0" to 10," but this is often unpredictable. Desert terrain also varies from place to place, the common factor being lack of water TERRAIN There are three types of deserts: Mountain, Rocky Plateau, and Sandy or Dune. Mountain deserts have scattered ranges or areas of barren hills or mountains separated by dry, flat basins. High ground may rise gradually or abruptly from flat to a height of several thousand feet. Most of the infrequent rainfall occurs on high ground and runs off rapidly in the form of flash floods, eroding deep gullies and ravines, leaving sand and gravel around the edges of basins. Rocky plateaus are relatively flat with places where solid or broken rock occurs at or near the surface. There may be cut or dry, steep-walled eroded valleys known as wadis in the Middle East. YOU CAN'T DRINK TOO MUCH WATER! Sandy or dune deserts are extensive, flat areas covered with sand or gravel, the product of ancient deposits or modern wind erosions. "Flat" is relative in this case, as some areas may contain sand dunes that are over 1,000 feet high and 10 to 15 miles long; trafficability in such areas will depend on windward/leeward gradients of the dunes and texture of the sand. Other areas may be totally flat for distances of 3,000 m or more. DESERT DRIVING TECHNIQUES: SAND: Sandy desert may be relatively flat or broken up by dunes. When driving in sand, the following techniques should be used: The best time to drive on sand is at night or early morning when the sand is damp and traction is better. DRIVERS, be wary of a lack of steering response in your tracks; this indicates that sand is building up between the rear sprockets and treads. If you allow this to continue, the sand will build up and force the track off. "Shaking" the vehicle with the steering or backing up will throw off the sand. Vehicle loads must be evenly distributed. You should use rear wheel drive where necessary to avoid digging in the front wheels. DRIVERS, switch to all wheel drive or change gears before a vehicle bogs down. You should select a gear before entering sand that will allow your vehicle to keep as much torque as possible without causing the wheels to spin and to minimize changing gears. Some areas will be covered by a surface crust. This is caused by chemicals cementing sand particles together. In some cases it will be possible to drive on this crust and keep the dust down. Crossing dunes requires careful reconnaissance. Normally, the upwind side of a dune will be covered by a crust and have a fairly gradual slope. The downwind side will be steeper and have no crust. Before crossing a dune, you should climb it on foot, checking the crust thickness, the angle of the crest to ensure that the vehicle will not become bellied up at the top, and the degree of slope and softness of the downwind side. If you are satisfied your vehicle can climb the dune, you should drive the vehicle straight up the dune at best speed, crest it and maintain a controlled descent on the other side. HILLOCK AREAS: The wind may have built up sand around small shrubs forming little hills. You should not try to drive wheeled vehicles through these areas without engineer assistance. THORN AREAS: Cacti or thorn bushes will cause frequent tire punctures. When operating in areas with this type of vegetation, you will need to increase the number of tires carried in your unit's PLL. ROCK: Rock and boulder-strewn areas, including lava beds, may extend for many miles. Desert rocks, eroded and sharp-edged, vary in size and are so numerous that it is almost impossible to avoid any but the largest. The harsh jolting will wear you out and severely wear tracks, wheels, springs and shock absorbers. Vehicles can follow one another in this type of terrain, and it may be possible to reconnoiter and mark a route. DRIVERS, try to get a rolling effect as you cross large rocks by braking as your vehicle wheels ride over a rock so the axle settles relatively gently on the other side. GETTING LOST OR STRANDED: People die every year in the desert because they don't know what to do if lost or stranded. It is a good idea to have at least two vehicles in your traveling party (use the buddy system). When driving, avoid going down steep slopes your vehicle may not be able to climb back up. Look for washouts, large rocks, and deep sand. If you get stuck, try jacking the vehicle up and then placing boards, brush, or blankets under the tires. Always let someone, friends or superiors know where you are going, when you plan to return, and when to start searching if you don't return. Don't forget to check in when you return! If lost, DON'T PANIC Remember the sun rises in the east and sets in the west. When departing from your field site, know the direction in which you are departing. If needed, make a field expedient compass. Put a stick in the ground; lay a rock at the end of the shadow from the stick. Wait 15 minutes. Draw a line from the rock to the new end of the shadow. The line represents the east-west line. If your vehicle breaks down, stay near it. Your emergency supplies are there. Your vehicle has many other items useful in an emergency. Raise hood and trunk lid to denote "help needed." A vehicle can be seen for miles, but a person on foot is very difficult to find. Tie a white or light-colored cloth to your antenna. Use mirrors and burn oil for signaling. When not moving, use available shade or erect shade from tarps, blankets, seat covers--anything to reduce the direct rays of the sun. Do not sit or lie directly on the ground; it may be 30 degrees or more hotter than the air. If you have water DRINK IT. Do not ration it. If water is limited, keep your mouth shut. DO NOT TALK, eat, smoke, drink alcoholic beverages, or take salt. Keep your clothing_on. It helps keep the body temperature down and reduces the dehydration rate. COVER YOUR HEAD. If a hat or cap isn't handy, improvise. CLIMATE AND WEATHER TEMPERATURES: The highest known air temperature recorded in deserts was 136 degrees F. Lower temperatures than this produced internal tank temperatures of about 160 degrees F in the Sahara Desert during World War II. The cloudless sky of the desert will permit the earth to heat up during the day, yet cool to near freezing at night. WINDS: Desert winds can achieve almost hurricane force; dust and sand suspended within them can make life almost intolerable, maintenance very difficult, and restrict visibility to a few meters. Sometimes these winds can last for days at a time. Although there is no danger of your being buried alive by a sandstorm, you can become separated from your unit. In all deserts, rapid temperatures changes invariably follow strong winds. RAIN: The most common characteristic of all deserts is the lack of water. Rain, when it occurs, may consist of one single violent storm in a year. That causes high surface water runoff which, depending on soil consistency, will either reduce trafficability in loam of wadis or somewhat improve it if the terrain is pure sand. Precipitation may occur in the form of hail even though ground temperature is in the 90s. Also, rain occurring as much as several hundred miles away can cause flooding in another distant location. Otherwise dry stream beds can suddenly become hazardous as a channel of flooding. Therefore, minimize the time you spend in these low-lying areas. Do not set up camp in dry stream beds; stories of walls of water 10 feet high roaring through them are true. Beware of rain clouds you see in the distance. Stay out of wadis! LIGHTNING: Remember lightning does strike frequently in the desert. Again, don't panic, keep exposure down to a minimum. Track vehicles are grounded, so you're better off inside than running around in the open. LIGHT: A powerful sun and low cloud density combine to produce unusually bright and glaring light conditions during the day. In certain circumstances, light allows such unlimited visibility that gross underestimation of distance is common. Look at the base of mountains when judging distances. Visibility conditions may, however, be degraded by mirages or heat shimmer, especially if you are looking into the sun or through optics. Because mirages distort the shape of objects, particularly in the vertical dimension, positions you selectfor observation posts should be as high as possible. Vision with night observation devices and even with the naked eye is extremely good on moonlit nights. A good way to measure distance is the use of the vehicle's odometer. BEFORE PUTTING CLOTHES ON IN THE FIELD, CHECK FOR_CRITTERS! VEGETATION AND WILDLIFE VEGETATION: The vegetation and wildlife of a desert have physiologically adapted to the conditions. Some plants have extensive lateral root systems to take advantage of the occasional rain, while others have deep roots to reach sub-surface water. For example, a palm tree indicates there is water within 2 to 3 feet of the surface; salt grass implies that water is about 6 feet deep; cottonwood and willow trees indicate water at a depth of 10 to 12 feet. The available vegetation is usually inadequate to provide much shade, shelter or concealment, especially from the air. Lack of natural concealment has been known to induce temporary agoraphobia (fear of open spaces) in some soldiers new to the desert, but this fear normally disappears after acclimation. INVERTEBRATES--(SPIDERS, CENTIPEDES, SCORPIONS): Invertebrates, such as grounddwelling spiders, scorpions, and centipedes, together with insects of almost every type, are found in quantity in the desert. Drawn to man as a source of moisture or food, lice, mites, and flies can be extremely unpleasant and carry diseases such as scrub typhus and dysentery. The stings of many scorpions and the bites of centipedes or spiders can be extremely painful, though seldom fatal. Some species of scorpions and spiders, however, can cause death. When you camp, check your clothes and shoes before putting them on every morning; in heavy infested areas, they may invade these items at night. SNAKES AND REPTILES: Snakes and reptiles are perhaps the most characteristic group of desert animals. Lizards and snakes occur in quantity, and snakes are probably the most common threat. Watch where you step. They are especially active at night during hot weather, and may be seen coiled in shady spots during the day. DON'T PLAY WITH SNAKES! FIRST AID FOR SNAKE BITE: Take no chances and treat all snake bites as poisonous. Follow these steps: 1. Remain calm, but act swiftly. Call MEDEVAC immediately. 2. Within practical limits, keep the bitten part very still, below the level of your heart and as cool as possible. 3. If the bite is on an arm or leg, place a constricting band (narrow cravat [swathe], or narrow gauze bandage) one to two finger breadths above and below the bite. If the bite is on the hand or foot, place a single band above the wrist or ankle. The band should be tight enough to stop the flow of blood near the skin, but not tight enough to interfere with circulation. In other words, it should not have a tourniquetlike affect. If no swelling is seen, place the bands about 1 inch from either side of the bite. If swelling is present, put the bands on the unswollen part at the edge of the swelling. If the swelling extends beyond the band, move the band to the new edge of the swelling. (If possible, leave the old band on, place a new one at the new edge of the swelling and then remove and save the old one in case the process needs to be repeated.) If possible, place an ice bag over the area of the bite. DO NOT wrap the limb in ice or put ice directly on the skin. Cool the bite area - do not freeze it. DO NOT stop to look for ice if it will delay evacuation and medical treatment. 4. All snakebite victims should be taken to the treatment facility as soon as possible. 5. Unless the snake has been positively identified, attempt to kill it and send it with the casualty. BE CAREFUL WHERE YOU SLEEP IN THE DESERT! The desert has few areas that offer protection, such as trees, from large vehicles. During short halts, sleep in or on your vehicle. When halting for more than an hour or so, designate a sleeping area that has a protective perimeter and always let someone know where you plan to sleep. When moving vehicles into an area where troops might be sleeping, use ground guides to look for sleeping troops. Do not sleep directly on the ground; besides the ground being hotter than the air above ground, snakes, spiders, and scorpions will have more difficulty in getting to you if you're on a cot. YOU USE LESS WATER IF YOU KEEP YOUR CLOTHES ON! Back to Table of Contents -- Winning in the Desert Back to CALL List of Issues Back to MagWeb Magazine List © Copyright 2004 by Coalition Web. Inc. This article appears in MagWeb.com (Magazine Web) on the Internet World Wide Web. Other articles from military history and related magazines are available at http://www.magweb.com