How to use geographical knowledge to determine the direction on a cloudy day?

Judging the direction in the wild There are many ways to judge the direction and position in the wild. Here are several commonly used methods: 1. Using the compass (north needle): Place the compass or the north needle horizontally so that the bubble is centered. After the magnetic needle comes to rest, the end marked N points to north. In addition to measuring true north, a compass or compass can also measure the specific direction of a target. The method is to align the compass sight with the target, or align the 0 scale on the dial with the target, so that the target, 0 scale and the magnetic midpoint are on the same straight line. After the compass is horizontally stationary, the scale pointed by the N end is From the bearing of the measurement point to the target, if the N end of the magnetic needle points to 36, the target is 36 degrees north by east of the measurement position. Although it is easy and quick to use a compass or compass to identify the direction, you need to pay attention to: 1) Try to keep it as level as possible; 2) Do not get too close to magnetic materials; 3) Do not mistake the S end of the magnetic needle for north, causing a 180-degree direction error ; 4) Grasp the magnetic declination in active areas and make corrections. 2. Use the sun: On a clear day, you can easily know the east and west based on sunrise and sunset, and you can also determine the direction. But it can only be roughly estimated. There are several more accurate measurement methods: 1) Watch direction finding. "Half hours point to the sun, and 12 points to the north." Generally, the direction can be quickly identified between 9 am and 4 pm. Use the direction of half the time to point to the sun. 12 o'clock points to the north. , such as 14:40 in the afternoon, half of which is 7:20, the hour hand points to the sun, then 12 points to the north, or if the watch is placed horizontally, the hour hand points to the sun, the reverse extension direction of the hour hand and the 12 scale bisector is North; or stand a small stick vertically in the center of the watch and rotate the watch so that the shadow of the stick coincides with the hour hand. The bisector between this time and the 12 o'clock scale is north. It must be noted that when determining the direction, the watch should be placed flat; it should not be used around noon in areas between 20 and 30 degrees north and south latitude. 2) Solar shadow direction finding. A wooden stick is erected on the ground. The shadow of the stick moves with the change of the position of the sun. These shadows are shortest at noon. The line connecting the ends is a straight line, and the vertical line of the straight line is the north-south direction. Draw a series of concentric circles on a piece of 50×50 cm drawing paper. The radius of the concentric circles increases in 1 cm increments. Nail it on the flat plate and fix it horizontally. Place a 12 to 15 cm long thin steel needle or needle-like object. Insert vertically in the center of the circle. When the position of the sun changes, the endpoints of the shadow will always intersect with the concentric circles. Plot these points, and then connect the two points on the same circle with straight lines. Connect the points of these straight lines to the center of the circle. This connection is the north-south line. , the direction of the arc top is north. ======================== 1. Use natural features to determine direction. In the absence of terrain maps and compasses, you must learn to use some natural features to determine direction. First of all, the sun is the most reliable "north needle". We know that the sun moves from east to west, and the shadow moves from west to east. For example, at 6 o'clock in the morning, the sun rises from the east, and the shadows of all objects turn to the west; at 12 noon, the sun is due south, and the shadows point north; at 6 p.m., the sun reaches due west, and the shadows point east . Therefore, the direction can be roughly determined by the shadow of the sun and objects. As the saying goes: "Get immediate results", use a benchmark (straight pole), make it perpendicular to the ground, and place a stone at the vertex A of the benchmark's shadow; after about 10 minutes, when the apex of the benchmark's shadow moves to B, place another stone The stone connects two points A and B into a straight line. The direction of this straight line is east-west. The direction perpendicular to line AB is north-south. The end facing the sun is south and the opposite direction is north (Figure 5). To measure the direction according to this method, the higher, thinner, and more perpendicular the pole is to the ground, and the longer the shadow moves, the more accurate the measured direction will be. Especially around 12 noon. For example, the shadow lengths at 11:30 and 12:30 are almost equal, the line connecting the vertices just points to the east-west direction, and the vertical line of the connecting line can also point to the north-south direction more accurately. The earth rotates 360 degrees in 24 hours, 15 degrees in one hour, and the hour hand of the watch always rotates twice as fast as the sun. Based on this principle, the position can be roughly determined with the watch and the sun.

At 6 o'clock in the morning, the sun is in the east and the shadow points to the west. At this time, point the hour hand on the watch to the sun, and the number "12" on the dial will point to the west. If the dial is rotated 90 degrees, it will be halved at 6 o'clock, so that the number "3" on the dial will be "" faces the sun, and "12" points to the north; at 12 noon, when the sun is in the south, fold 12 in half so that the "6" on the dial faces the sun, and "12" still points to the north (Figure 6) . When determining direction according to this method, local time difference must be taken into consideration. Beijing time should be converted into local time. Taking 120 degrees east longitude as the standard, for every 15 degrees of longitude eastward, Beijing time will be added by one hour, and for every 15 degrees of longitude westward, Beijing time will be subtracted by one hour, which is local time. For example, the geographical coordinates of Urumqi are 87 degrees and 40 minutes east longitude, then (120°-87°)÷15°=2 hours and 9 minutes. Subtract 2 hours and 9 minutes from Beijing time to get the local time in Urumqi. The above two methods cannot be used in summer in areas south of the Tropic of Cancer (23 degrees 27 minutes north latitude) in Chiayi, Taiwan, Nan'ao Island northeast of Shantou, Guangdong, Wuzhou City, Guangxi, and Gejiu City, Yunnan. By the way, we know that when the earth rotates, the relative positions of the earth and the sun move 15°. We can use a watch and the sun to roughly determine the direction. Conversely, we can also use a compass and the sun to determine the approximate time. The method is to point the north direction with a compass and divide the reading of the sun's direction by 15. In our country, Beijing time is used as the standard. Beijing is on the 120° east longitude line. Other areas should be corrected based on longitude differences to obtain the correct solar time. As the saying goes: "All things grow by the sun." The heat energy of the sun has formed many characteristics in nature that indirectly determine direction. After mastering these characteristics, you can still determine the direction based on them even on a cloudy day without the sun. For example, the grass on the south side near tree stumps, tree trunks and large rocks grows taller and more lush. In winter, the grass on the south side also withers and turns yellow faster. The bark is generally smoother on the south side and rougher on the north side (there are many cracks and uneven bumps on the bark). This phenomenon is most obvious in birch trees. The bark on the southern side of the birch tree is lighter in color than the northern side and is more elastic. In summer, the gum resin flowing out from the trunks of pine, cypress and fir trees is more abundant in the south than in the north, and the clumps are larger. The secondary bark covering the pine trunks forms earlier than the south and develops higher upwards. This phenomenon is more prominent when the bark swells and turns black after rain. In autumn, the south-facing side of fruit trees has dense branches and leaves and produces more fruits, especially apples, red dates, persimmons, hawthorns, lychees, citrus, etc. When the fruit is ripe, the south-facing side is stained first. Ant nests under trees and near shrubs are always to the south of the trees and shrubs. Moss growing on stones likes moisture and cannot tolerate sunlight, so moss usually grows on the north side of stones. The leaves of Mongolian chrysanthemum and wild lettuce on the grassland point north and south. In the mountains and hilly areas of northern my country, dense arbor forests mostly grow on shady slopes, while shrubs mostly grow on sunny slopes. This is because soil water on shady slopes evaporates slowly and soil and water conservation is good, so vegetation recovery is faster than on sunny slopes and forests are easy to form. In terms of tree habits, fir, spruce, etc. grow well on the north slope, while masson pine, Huashan pine, birch, poplar, etc. mostly grow on the south slope. In spring, the side of snow that melts first faces south, and the side that melts later faces north. The pits and depressions in the north face the sun and melt snow earlier. Most rivers in the northern tundra zone have gentle northern banks and steep southern banks. In addition, most temples, pagodas and general houses face north and south. The doors of Islamic mosques face east (worshippers face west). Polaris is often used to determine direction at night. To find the North Star, you must first find the Ursa Major constellation (commonly known as the Big Dipper), because it always maintains a certain positional relationship with the North Star and keeps rotating. After finding the Big Dipper, follow the line connecting the two stars A and B on the edge of the spoon and extend toward the mouth of the spoon. At about five times the distance between the two stars A and B, there is a brighter star, which is the Polaris. In areas south of 40 degrees north latitude, the Big Dipper often turns below the horizon. Especially at dusk in winter, it is often invisible. At this time, the North Star should be found according to the Cassiopeia constellation opposite the Big Dipper. The Cassiopeia constellation consists of 5 stars that are about the same brightness as the Big Dipper, forming a "W" shape. Polaris can be found in front of the middle of the "W" gap, about twice the width of the entire gap. In areas south of 23 degrees north latitude, the Southern Cross constellation can be used to determine the direction in the first half of the year. The Southern Cross constellation is mainly composed of four bright stars, which are connected diagonally to form a cross. Extending downward along the line connecting the two stars A and B, it is due south at about four and a half times the distance between the two stars. You can also use the moon to determine the direction at night.

The moon rises and sets in a regular pattern. The moon rises every day 48-50 minutes later than the previous day. For example, at 18:00 on the 15th day of the lunar calendar, the moon rises from the east. On the 20th day of the lunar calendar, which is 5 days apart, it rises about 4 hours late and appears in the eastern sky at about 22:00. The moon phase changes of the moon's "waxing and waning" are also regular. Before the fifteenth day of the lunar calendar, the bright part of the moon is on the right, and after the fifteenth day of the lunar calendar, the bright part of the moon is on the left. The first half of the month is called the "first quarter moon", the middle of the month is called the "full moon", and the second half of the month is called the "last quarter moon". Every month, the moon rises and sets according to the above two laws. To use the moon to determine the orientation, refer to the table below. In addition, the direction can be roughly determined based on the rule that the moon takes about 12 hours to turn from east to west, with an average rotation of about 15 degrees per hour, combined with the moon phase, position and observation time at that time. For example, at 10 o'clock in the evening, if you see that the right half of the moon in the night sky is lit, you can tell that it is the first quarter moon. The sun sets at 6 o'clock and the moon is due south. At this time, 10 o'clock - 6 o'clock = 4 o'clock, that is, 4 o'clock has passed. hour, the moon rotates 15°×4=60° during this period. Therefore, deflecting the moon's position 60 degrees to the left (east) at this time is due south. In nature, wind can also help us determine direction. For example, the windward side of wooden pillars is dark and easy to rot, while the windward side of cliffs and stones is relatively smooth. But you must be familiar with the prevailing local wind direction, which is especially important in desert areas. Wind is an important factor in shaping the surface morphology of deserts. In areas with a single wind direction, crescent-shaped dunes and dune chains are generally dominant. The windward side of dunes and sand ridges has a gentler slope; the leeward side has a steeper slope. In the northwest region of my country, due to the prevailing northwest wind, sand dunes generally form northwest to southeast. The northwest side of the dune has a small slope and the sand is harder, while the southeast side has a steep slope and the sand is soft. Under the influence of the northwest wind, plants in the desert area, such as butter grass, tamarisk, Haloxylon ammodendron, camel thorn, etc., tilt toward the southeast. The door of the yurt also usually faces the leeward southeast direction. In winter, many small snow ridges and sand ridges are often formed near withered grass. Their heads are large and their tails are small. The direction of their heads is northwest. The above are the general characteristics of desert areas. Wind direction also varies by region and season. Therefore, you should determine the direction based on the characteristics of the wind direction. You should usually refer to the topography of Bingyao to understand the prevailing wind direction in the four seasons in order to make a correct judgment. It should also be noted that in areas with multiple wind directions and roughly similar wind forces, pyramid-shaped sand dunes will appear. Determining the direction in this area is more complicated, and you should refer to the sun, moon and stars for comprehensive judgment. It is worth mentioning that people are familiar with the sayings that "the branches and leaves of independent large trees are usually denser in the south and the branches and leaves in the north are sparse." and "the annual rings of the stumps of independent trees usually have smaller intervals in the north and larger intervals in the south." However, In practice it is more complicated. In 1945, the former Soviet Union M. Belyakov pointed out after systematic observation: "You cannot use the branches, leaves and annual rings of trees to determine the direction. The leaves are usually lush not in the south, but in the free space. As far as independent trees are concerned In addition to sunlight, wind and other factors also have a huge impact, and it is often unreliable to determine the direction. Similarly, even the annual rings of independent trees are not necessarily wide in the south; it is not only the sun that affects the width of the annual rings. There is also wind; in addition, there are vertical changes in the width of the annual rings, and different results will be obtained when cutting trees at different heights." According to field observations, Belyakov's view has some truth. For example, the independent trees in the valley of Helan Mountain in Ningxia are affected by the perennial westerly wind, and all their branches and leaves face the east instead of the south. When using natural features to determine orientation, special attention should be paid to specific analysis of specific situations and never to apply mechanically. When identifying the direction, be sure to pay attention to the comprehensive use of multiple methods to complement and verify each other. Our country has a vast territory, and the natural conditions in various regions vary greatly. On the basis of mastering the general laws, we must also pay attention to the special laws of each region in order to make correct judgments. What to do if you lose your way. When traveling in the wild, the original road disappears, or the route is never determined from the beginning, and you just rely on the terrain and direction to travel, but cannot find the location. This is a loss of direction. When you find yourself lost, do not panic and change your direction. You should stop immediately and calmly recall the path you have taken, try to redirect yourself according to all possible signs, and then find the road again. The most reliable way is to "return when you have lost your way", follow your own footsteps and return to the original starting point, and do not rush blindly. Returning to the original route sometimes requires a lot of determination. Especially when you have already climbed a mountain, making a temporary decision to change your route and take the arduous road back requires more courage and perseverance than moving forward.

When you find that you are disoriented, you should first climb up and look far away to determine where to go. This is especially true in mountainous areas. First, climb to a nearby large ridge to observe, and then decide whether to continue climbing up or down. You should usually walk in the direction of low ground so that you can easily reach the water source. It is safest to follow the river, which is especially important in the forest (jungle). As the saying goes: "Water can transport people home" because roads and residential areas are often built along waterfronts. In mountainous areas, if the mountain range has a clear trend and the ridge slope is gentle, you can walk along the ridge. Because the ridge has a wide view, it is easy to observe the road conditions and determine the location. The ridge also has a certain guiding role. As long as you move along the ridge, you can usually reach a certain goal. When traveling in vast flat deserts, Gobi deserts or vast forests and snowfields, people generally do not walk in a straight line in the above areas because of the single scenery and lack of directional objects, and usually veer to the right. The average person's left step is slightly larger than the right step by 0.1 to 0.4 mm, so they turn to the right unknowingly while walking. Walkers usually walk in a circle with a diameter of about 3 to 5 kilometers, which is known as "ghost beating the wall". In order to avoid taking detours and wasting time when traveling in the desert or forest, it is very important to move in a straight line in a certain direction. When walking in the above areas, you can use the wind blowing in one direction for a long time or the clouds that move quickly in one direction to determine the direction. Walking against the wind or clouds or keeping a certain angle with them can ensure that you move in a straight line within a certain period of time. You can also use the "stacked marking method", that is, every time you walk a certain distance, make a mark behind your back (such as placing stones, inserting branches, or carving marks on the trunk with a knife or ax), and constantly look back at the route you are taking. If the mark is on a line, you can know whether it has deviated from the direction. During the Liberation War, when the People's Liberation Army was suppressing bandits in the Northeast, some scouts used this method to travel to and from the vast forests, seas and snowfields to collect and deliver intelligence. The scenery in desert areas is monotonous and often disorienting. Due to the action of wind in the desert, the sand dunes move and the roads are not fixed. You can identify the road by looking at the droppings of horses, donkeys and camels on the ground. Generally speaking, the patterns are the routes traveled by humans and animals. If you really have no way to go, you can follow the camel's tracks. In the thirsty desert, camels have a special sensitivity to water and can often find water sources. In fixed and semi-fixed sand dunes and grassland areas, there are few but relatively straight roads with little change. As long as you maintain the general direction of travel, you can keep going. In areas with quicksand, some road sections will be covered, and there will be detours to the left and right. The distance of such detours is generally not very far. You should return to the original direction of travel in time, and do not go straight down the fork road and go astray. In desert areas, you should also be careful not to be fooled by mirages. Walking in the forest, the dense canopy of trees blocks out the sky and the sun, making it impossible to see the sun, moon and stars. When entering the forest, to avoid getting lost, you should study the local topographic map clearly. Pay special attention to the linear features on both sides of the direction of travel that can be used as directions, such as rivers, roads, mountains, long lakes, etc. Pay attention to whether its position is to the left or right of the travel route, and whether it is parallel to the route. If you find that you are disoriented, you should immediately move in the direction of the pointing object until you reach the point, and then determine the direction. If you are lost in the forest, you should first estimate how far you have walked from the place where you can determine your direction, then look for a tree trunk nearby that is easy to see, and use a knife or ax to scrape the skin to make a circular mark (that is, scrape off the skin around the tree trunk so that you can remove any traces from the tree trunk). You can see it in all directions), and then walk back according to your memory. If you can't find the original location, go back to the marked place and try again in another direction. In the end, the goal is always found. In the forest, if you are not paying attention, it is difficult to distinguish between paths in the forest and gaps between trees. The paths that people often walk on have become hard and solid due to frequent trampling on the road surface. However, it is important to note that not all trails with solid pavement are pedestrian paths. If the upper body often touches grass and vine branches, but the lower body is not entangled by these debris, it may be the path of wild beasts. In the dark, this sense of judgment is more acute and accurate than during the day. In this case, you should return to the sidewalk immediately. People who are inexperienced or unfamiliar with the roads will usually get lost when walking through the forest at night. Therefore, do not travel at night unless there are special circumstances. In the jungle areas of the southwest border of my country, there are many ethnic minorities living, and they are often used to cutting down the trees on the mountains near the village. Therefore, after getting lost in such an area, you can climb up a tree or a high place to look around. If you find that there are no trees on a certain mountain, there will often be people near that mountain. In addition, the houses of ethnic minorities such as the Dai people are mostly made of bamboo, and they are used to planting large bamboos next to their villages. Therefore, it is easy to find cottages wherever there are large bamboo trees.

It’s frustrating when you’re lost and there’s no way to go, and it’s frustrating when there are many roads to follow if you encounter a fork in the road. At this time, you must first clarify the direction you want to go, and then choose the right path. If several roads have roughly the same direction and cannot be determined, you should choose the middle road. This way you can get the best of both worlds, and even if you go wrong, you won't deviate too far. After getting lost, it was getting late. You should choose a camping site immediately and do not wait until dark, otherwise you will be very passive. If you feel very tired, you should rest immediately and don't stop until you are exhausted. This should be especially noted in winter. Excessive fatigue and excessive sweating can easily lead to frostbite or freezing to death. Losing direction is not a fear to a calm and determined soldier. As the old saying goes: "There is no way out despite mountains and rivers, and there is another village with bright willows and flowers." When you are lost, as long as you calmly analyze and determine the direction based on some characteristics of nature such as the sun, moon and stars, and strengthen your confidence, you will definitely break through the siege of "over mountains and rivers" , enter the realm of "a bright future"! If you need rescue, you can light a fire at a high place at night; smoke can be combustible during the day. Putting grass on the fire will emit white smoke. Put the grass on the fire every ten seconds. The correct method is 6 times per minute. This is a universal rescue signal. If you are in a forest, you can hit the birch trees with an ax or a stick, because the sound of birch trees is loud and spreads far. In open areas, such as grass, beaches, and snow, ground signs can be made according to local conditions. For example, cut the grass into certain marks, step on the snow, or use trees and rocks to place corresponding marks to communicate with the sky. 75