What are the mysteries of the Eskimo igloos?

Within the Arctic Circle, there is an inexhaustible supply of ice, as well as an inexhaustible supply of water. Every time before winter, the Eskimos built igloos. They took local materials and first processed the ice into regular rectangular pieces, which are "bricks"; Use water as "mud".

After the materials are ready, they choose a good place, splash some water, put some ice cubes, splash some water, and build some ice cubes; The front side is constantly frozen, and the back side is constantly frozen, and the finished house becomes an igloo that freezes into a whole. This type of house is sturdy and has been hailed as an enviable masterpiece of art by the Eskimos. But ice is a symbol of coldness, and the mention of it makes people shudder.

How do Eskimo igloos keep warm from the cold? First of all, because the igloo is strong and impermeable, it can keep the cold wind out, so the people who live in the igloo can be protected from the cold wind.

Secondly, ice is a poor conductor of heat, which is well insulated, and the heat in the house can hardly be conducted through the ice wall to the outside of the house.

Again, the igloo is frozen into a single unit, with no windows and an animal skin curtain hanging at the door, which greatly reduces the convection of the air inside and outside the house.

Because of this, the temperature inside the igloo can be kept at minus a few degrees to more than ten degrees, which is much warmer than outside the house where it is more than minus 50 degrees. Eskimos put on leather coats and can survive the winter in such igloos. Of course, the temperature in the igloo is much lower than the indoor temperature we have in winter, and no fire is allowed in the igloo for heating, because the ice melts into water above 0.

So, can you explain why the lower river does not freeze in winter? This is due to the properties of water: water at 0 4 has the property of abnormal expansion, which ordinary substances do not have; Water with a temperature above 4 still follows the general property of thermal expansion of matter.

The reality is that the volume of water is minimum at 4 and maximum at 0. Like all substances, the mass of water does not change with temperature, according to the concept of density = mv, the density of water is known to be maximum at 4 and minimum at 0. Then, according to the floating and sinking conditions of the object, we know that the water (substance) with low density is at the top and the water with high density is below.

After freezing in winter, the upper layer of the river will freeze when it is not solid; The temperature below the ice is in order, so the lower river water will not freeze above 0.

In addition, ice is a poor conductor of heat, and a thick layer of ice is more conducive to preventing heat transfer, so that the heat of the water under the ice layer is not easy to dissipate and condense into ice. As a result, a large number of organisms are able to survive and thrive in the water.

Why do Eskimo igloos store heat and not melt? Knowledge.

The unique cultural identity of a people is often the best way for them to adapt to the natural environment in which they live. This situation is often seen in the relatively backward national cultures that exist in the world today. For example, the culture of the Eskimos living in North America is characterized by snow sleds, igloos, etc., which are the best cultural mechanisms for adapting to the polar climate.

If the Eskimos were to move to desert areas, they would inevitably abandon the original culture represented by sleds and igloos, and adopt a desert culture characterized by camels and tents, otherwise they would be eliminated by natural patters. Here, the natural principle of survival of the fittest is very important.

Within the Arctic Circle, there are many inexhaustible sources of water. Eskimos build igloos every winter. After the materials were ready, they sprinkled some Lingyu filial piety water on the selected place, sprinkled some ice cubes, and then sprinkled a few ice cubes; The front is constantly sprinkled with ice cubes, and the back is constantly sprinkled with frozen ice cubes, and it becomes an igloo that freezes into a whole.

The house is sturdy and has been hailed as an enviable masterpiece of Eskimo art. The reason why the Eskimo igloo can keep warm and protect from the cold is that because the igloo is strong and impermeable, it can keep the cold wind out, so the people living in the igloo can be protected from the cold wind; Secondly, the temperature of the igloo can reach more than one-third of that indoors without being affected by the excessively high outdoor temperatures. The roof of the igloo, which is frozen into one piece again, has no windows and animal skin curtains hanging on the roof, which greatly reduces the convection of air inside and outside the house, and there is a large window on the roof that allows you to see the distance between the roof and the walls.

In such igloos, Eskimos can safely survive the winter in leather coats. Of course, the temperature of the igloo is much lower than the indoor temperature we have in winter, and it is also not allowed to make a fire for heating.

Because the design structure of the igloo is very special. The igloo was designed with the principle of hot air rising and cold air falling in mind, so when it was built, a pit was dug down inside the foundation. Humans are surrounded by heat in the igloo, and the ice allows the cold orange air to descend into the pit.

The heat in the human body is in the igloo, forming an internal circulation, and with the passage of time, the internal temperature and air will be higher than the external temperature. The inner ice cave is insulated from the snow to resist the cold, and with the addition of heat circulation, people live in a burning furnace. So it's not cold at all.

Do igloos really keep warm? Discover the secret of keeping the Eskimos warm, which is priceless wisdom.

The igloo is round, which not only blocks the biting cold wind, but also protects the roof from melting. The practice of digging deep holes and building shallow roofs in the snow room makes it warmer for people to live underground in winter than on the ground.

Igloos were built, and in order to protect them from the wind and snow and the cold, the Inuit often had to cover the hemispherical roof with a thick layer of weeds and a layer of seal skin; At the same time, the spiral-shaped walls of the house are covered with animal skins to protect against the cold. Another way to keep out the cold is to shade the windows, which are generally made of transparent sea beast intestines, which only transmit light and are not breathable, which is very distinctive.

In the igloo, the Inuit also built a fire to keep warm from the cold, and they hewed a stone stove out of stones, which was filled with oil fried by sea beasts, and kneaded into a wick with animal hair, which was lit even when it was minus degrees Celsius outside.

The low temperature of 30 or 40 degrees Celsius is still quite warm in the house. Some igloos don't have doors at all, but dig a passage from the ground as a door after the igloo is built, so that the room is warmer.

The igloo construction process.

Cut the snow bricks. The igloo is made of snow bricks of various sizes. The first step in building an igloo is to choose an open, sunny flat area, determine a specific foundation, and then use a sharp knife to cut it into large snow bricks of various sizes, so that you can build an igloo. Later, with each superimposed circle, it shrinks inward a little, and the circle becomes smaller and smaller, until it forms a closed, hemispherical dome.

Open windows to draw light. Open a small window on the south side, and a plate-shaped snow block sticks out above the small window to block the snowflakes from hitting the window, and also to refract the sun's rays so that it can shine directly into the room, rather than on the large snow bricks on the north side. Because the angle of the sun around the Arctic Circle is so low in winter that the light sometimes shines almost obliquely from the southern horizon, the large snowboard above the window acts as a refractor, allowing the sun to illuminate the house, and sometimes even photograph.

Dig a hole in the door. A door was carved into the ground of the hemispherical igloo, which was so low and narrow that it could barely be considered a hole. Fortunately, the Inuit are naturally small and dexterous, and they can slip into the house with a simple slide in front of the igloo door, without any difficulty.

The next step was to dig a deep pit in the land covered by a hemispherical roof, which was a large part of the igloo, as it was both built and hewn. It is based on the horizon, both to the sky and to the ground, which is the beauty of the igloo and the ingenuity of the Inuit.

It is essential to build a roof upwards, but not too high, and dig a pit downwards as the main space of the house, it is best to be deeper, which is the most simple and reliable. Because digging a deep hole in the snow is definitely much easier and safer than building a high house in the sky.

There are three ways of heat transfer: heat conduction, heat convection, and heat radiation. Digging snow pits and building igloos in alpine areas is to use the heat transfer properties of ice and snow to create a place for themselves to keep warm and defend against cold, and rely on them to resist the severe cold of tens of degrees below zero. How can snow pits and igloos keep you warm and cold?

It seems that the cold snow pit igloo just happens to be able to cut off these several ways of heat dissipation. First of all, ice is a poor conductor of heat, and it is well insulated, and the heat in the house can hardly be conducted through the ice wall to the outside of the house. Secondly, the frozen igloo has no windows and hangs a curtain at the door, which can greatly reduce the convection of the air inside and outside the house.

In addition, the dense igloo also protects against the cold wind howling outside, keeping the occupants inside safe from attack. Because of this, the temperature inside the igloo can be kept at minus a few degrees Celsius to a dozen degrees Celsius, which is much warmer than outside the house at minus forty or fifty degrees Celsius.

Because their igloo is also based on a local custom, so they don't really live in a cold house.

In the ice and snow world, a person's body temperature needs to be maintained at about 37 in order to live normally. If the temperature of the snow is 0, the temperature difference between the inside and outside of the human body is 37. Under such a temperature difference, there is a continuous flow of heat from the human body to the outside of the body, if the human body does not get the corresponding energy supplement, the body temperature will gradually decrease, until frostbite or even freezing to death.

The so-called warm clothing is actually a clothing with a relatively small thermal conductivity. For example, if a person's clothes are made of wool felt with a thermal conductivity of 0 0419, when the temperature difference between the inside and outside of the 1 cm thick wool felt is 37, the amount of heat coming out of the body per unit area is about 155 joules per second. Obviously, although this person is wrapped in wool felt 1 cm thick, if he stays in the environment of 0 for a long time, he will still suffer frostbite, let alone in the harsh environment of minus 30 40 in the Arctic.

But why did the Eskimos survive a long, harsh winter in an igloo?

Here we still have to talk about the thermal conductivity. We know that the thermal conductivity of ice is much greater than that of wool felt, and for purer ice, the thermal conductivity is, that is, the thermal conductivity of ice is about 55 times that of cow felt. From the point of view of the warmth effect, the same 1 cm thick wool felt compared with ice, ice cannot keep warm.

However, the thickness of the ice cubes used by the Essom people to make igloos is about i meters, so that the thick ice blocks prevent the heat in the igloo from being transmitted, and the igloo made of thick ice blocks has a greater warmth effect than wool felt. In addition, the Eskimos also created some wind protection and other measures to keep warm, and this is how the Eskimos survived the harsh winter in thick igloos.