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The Ultralight
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Desert Survival
(Adapted from the U.S. Army Survival
Manual)
To survive in arid or desert areas, you
must understand and prepare for the environment you will face.
Your survival will depend upon your knowledge of the terrain,
basic climatic elements, your ability to cope with these elements,
and your will to survive.
TERRAIN
Most arid areas have several types of terrain.
The five basic desert terrain types are -
Mountainous (High Altitude).
Rocky plateau.
Sand dunes.
Salt marshes.
Broken, dissected terrain ( "gebel" or "wadi"
).
Desert terrain makes movement difficult and demanding. Land navigation
will be extremely difficult as there may be very few landmarks.
Cover and concealment may be very limited; therefore, the threat
of exposure to the enemy remains constant.
Mountain Deserts
Scattered ranges or areas of barren hills
or mountains separated by dry, flat basins characterize mountain
deserts. High ground may rise gradually or abruptly from flat
areas to several thousand meters above sea level. Most of the
infrequent rainfall occurs on high ground and runs off rapidly
in the form of flash floods. These floodwaters erode deep gullies
and ravines and deposit sand and gravel around the edges of the
basins. Water rapidly evaporates, leaving the land as barren
as before, although there may be short-lived vegetation. If enough
water enters the basin to compensate for the rate of evaporation,
shallow lakes may develop, such as the Great Salt Lake in Utah,
or the Dead Sea. Most of these lakes have a high salt content.
Rocky Plateau Deserts
Rocky plateau deserts have relatively slight
relief interspersed with extensive flat areas with quantities
of solid or broken rock at or near the surface. There may be
steep-walled, eroded valleys, known as wadis in the Middle East
and arroyos or canyons in the United States and Mexico. Although
their flat bottoms may be superficially attractive as assembly
areas, the narrower valleys can be extremely dangerous to men
and material due to flash flooding after rains. The Golan Heights
is an example of a rocky plateau desert.
Sandy or Dune Deserts
Sandy or dune deserts are extensive flat
areas covered with sand or gravel.
"Flat" is a relative term, as
some areas may contain sand dunes that are over 300 meters high
and 16 to 24 kilometers long. Traffic ability in such terrain
will depend on the windward or leeward slope of the dunes and
the texture of the sand. Other areas, however, may be flat for
3,000 meters and more. Plant life may vary from none to scrub
over 2 meters high. Examples of this type of desert include the
edges of the Sahara, the empty quarter of the Arabian Desert,
areas of California and New Mexico, and the Kalahari in South
Africa.
ENVIRONMENTAL FACTORS
In a desert area there are seven environmental
factors that you must consider -
Low rainfall.
Intense sunlight and heat.
Wide temperature range.
Sparse vegetation.
High mineral content near ground surface.
Sandstorms.
Mirages.
Low Rainfall
Low rainfall is the most obvious environmental
factor in an arid area. Some desert areas receive less than 10
centimeters of rain annually, and this rain comes in brief torrents
that quickly run off the ground surface. You cannot survive long
without water in high desert temperatures. In a desert survival
situation, you must first consider "How much water do I
have?" and "Where are other water sources?"
Intense Sunlight and Heat
Intense sunlight and heat are present in
all arid areas. Air temperature can rise as high as 60 degrees
C (140 degrees F) during the day. Heat gain results from direct
sunlight, hot blowing winds, reflective heat (the suns
rays bouncing off the sand), and conductive heat from direct
contact with the desert sand and rock.
The temperature of desert sand and rock
averages 16 to 22 degrees C (30 to 40 degrees F) more than that
of the air. For instance, when the air temperature is 43 degrees
C (110 degrees F), the sand temperature may be 60 degrees C (140
degrees F).
Intense sunlight and heat increase the
bodys need for water. To conserve your body fluids and
energy, you will need a shelter to reduce your exposure to the
heat of the day. Travel at night to lessen your use of water.
Radios and sensitive items of equipment
exposed to direct intense sunlight will malfunction.
Wide Temperature Range
Temperatures in arid areas may get as high
as 55 degrees C during the day and as low as 10 degrees C during
the night. The drop in temperature at night occurs rapidly and
will chill a person who lacks warm clothing and is unable to
move about. The cool evenings and nights are the best times to
work or travel. If your plan is to rest at night, you will find
a wool sweater, long underwear, and a wool stocking cap extremely
helpful.
Mirages
Mirages are optical phenomena caused by
the refraction of light through heated air rising from a sandy
or stony surface. They occur in the interior of the desert about
10 kilometers from the coast. They make objects that are 1.5
kilometers or more away appear to move.
This mirage effect makes it difficult for
you to identify an object from a distance. It also blurs distant
range contours so much that you feel surrounded by a sheet of
water from which elevations stand out as "islands."
Light levels in desert areas are more intense
than in other geographic areas. Moonlit nights are usually crystal
clear, winds die down, haze and glare disappear, and visibility
is excellent. You can see lights, red flash-lights, and blackout
lights at great distances. Sound carries very far.
Conversely, during nights with little moonlight,
visibility is extremely poor. Traveling is extremely hazardous.
You must avoid getting lost, falling into ravines, or stumbling
into enemy positions. Movement during such a night is practical
only if you have a compass and have spent the day in a shelter,
resting, observing and memorizing the terrain,
and selecting your route.
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Steve's Notes: In the dry air of the desert, you
may not feel like you are sweating, because your perspiration
can evaporate as fast as it comes. This can be very comfortable
compared to the "sticky" heat of more humid areas.
It also means it is easy to become dehydrated very quickly without
realizing it is happening. |
Go to Desert
Survival - Part Two.
Back to the Wilderness
Survival Guide.
The Ultralight
Backpacking Site | Desert Survival |