The transition in the desert during the hot daytime extremely exhausting. Physical activity during the march cause increased sweating and water losses lead to rapid dehydration. In addition to this direct solar radiation creates a risk of rapid overheating of the body, a thermal or heat stroke.
That is why the day's march in the desert is only allowed in extreme circumstances and only under the condition that the location of the village, artesian well or oasis precisely known distance to no more than 10 – 20 km, and the health of people can overcome it for 3 – 4 hours . With a take only what is needed – the jar with water, and an emergency radio signal means. Head, face and neck protection from the scorching sun cape-burnous, which cut out of any available fabric. The sand while walking missed the shoes, put blankets on top of it-shoe covers made of cloth, styanuv them just above the ankle laces. Glasses-filters well protect eyes from glare and fine sand dust, and in their absence, I close my eyes with narrow strips of fabric cuts. In transitions best to stick foot dunes. Here the ground is denser, and legs are not as deep sink in the sand. But at the same time maintain the direction of a lot harder. In order not to lose orientation, must constantly seek the help of a compass. If the sight is marked dune, wood, stone, you can move, focusing on them.
Often in the desert there is a very peculiar phenomenon – Fata Morgana or mirage. At midday, when the soil is heated by the sun, are formed in the surface atmosphere demarcated layers of air with different densities. As a result of refraction of sunlight on the desert horizon suddenly there swaying palms lake with domes, ridges, dunes floating in the air, and even cities. Quite often a mirage – an inverted lake with islands. Mirages occur not only during the day, but before sunrise, when the air is full of dust. These pictures are so vivid and distinct, sometimes mislead even the most experienced traveler, making the re-route.
Easier and safer transitions in the desert during the cooler night. The possibility of long-term transitions in the summer night with proven success members of the Almaty scientific-sport expedition led by Nikolai Kondratenko. In August 1982, the start of the hike to the floodplain Syr (near Kyzyl-Orda), they were eighteen nights on the sandy expanses of hot and Kum, breaking 520 km, reached the Amu Darya River, near Nukus. For the night and morning hours, they managed to go up to 30 miles, keeping the velocity of 2.5-4.5 km / h. They walked for quite a deserted place, focusing on the map, a compass and the stars, trying to get as close as possible to life-saving artesian wells drilled prudent geologists, spending frugally laid in 5 liters of water per day (the norm is quite modest for summer desert, when the air temperature in shadows constantly passes for 45 °). Only in extreme cases, they uncork emergency rubber vessel where water is stored. Of course, the success of the expedition – the result of a good athletic training, endurance and dedication of its members. But most importantly, the expedition found that compliance with the rules of transition in the desert, the rational allocation of water resources, the ability to navigate in the wilderness, to find water sources significantly increase the chances of people who were among the sandy expanses as a result of an emergency, a favorable outcome.
Transitions in the desert at night are performed in accordance with the general rules in compliance with the uniform rate movements, organizations large and small rest stops, etc. Particular attention should be paid on halts the feet dry wipe your feet and interdigital spaces, thoroughly shake out of her shoe caught in the sand and small stones. During the night march orientation usually lead by the stars. This method is the most simple, reliable, requires no stops along the way, and the cloudless sky allows you to use it all the time.
Grave danger is sandstorm – sandstorm. The first harbinger of the coming storm – silence. Wind suddenly died down, and the desert falls agonizing lull. No sound, no rustling, no whiff of even the lightest breeze. Becomes unbearably stuffy, as if the air is not enough oxygen.
Dark, almost imperceptible cloud on the horizon is increasing rapidly, zastilaya sky, turning in front of a huge black-and-brown cloud. It is getting closer and closer. Strange high, with metal shade sounds fill the air. This myriad grains collide with each other at a furious whirlwind. Sometimes sandstorm approaching a giant black-and-brown walls, rising to a height of several kilometers, eclipsing the sun. The wind speed is 50 m / sec or more. The only salvation for man, caught in a desert sandstorm – immediately go to the leeward side of the tree, the rock, stone, wrap the head in any fabric covering your nose and mouth with a handkerchief. Flask of water buried next to him.
Sandstorms usually short-lived, but may rage continuously for two to three days. But in any case continue to go to the next before the wind finally died down.