What sediments are in summer. §36. Precipitation. Atmospheric precipitation: precipitation types

The main factor that has a significant impact on the progress of flora and fauna of the Planet Earth is the presence of climate development favorable (temperature, humidity, various types of precipitation).

From this list, precisely, atmospheric phenomena create numerous climatic zones, which, in turn, differ in the diversity of life forms.

All sediments are inextricably linked with a cycle of water in nature - here include all phenomena that are formed on the basis of the physicochemical properties of water and its ability to be in three aggregate states - liquid, solid and vapor-shaped (3 types of precipitation).

At school, this topic takes place in the 2nd class on the subject of the "surrounding world."

What is precipitation

Strictly determining atmospheric precipitation in geography is made as follows. This term is called such phenomena arising in the Earth's atmosphere, which are based on the concentration of water in the air layer, as well as are associated with the transition of water dispersion into various aggregate states and losing to the surface of the planet.

The main classification of precipitation is separation of atmospheric front temperatures:

• registered - associated with warm air flows;
• storm - related to cold air masses.

To take into account the number of precipitation, which falls on the surface of the Earth in a specific region, meteorologists use special equipment - sedimentaries, which provide data measured in the layer thickness of the liquid water that has fallen on a solid surface. Units of measurement - millimeters per year.

Natural precipitations play a key role in the formation of the earth's climate and form the turnover of water in nature.

Views of atmospheric oyphans

Conditionally divided the types of precipitation on the basis of the aggregate state of the water in which it falls on the ground. It is fundamentally possible in two versions - solid and liquid form.

Based on this, the classification is as follows:

• liquid - (rain and dew);
• solid - (snow, hail and frost).

We will understand what is each of the types of such precipitation.

The most common type of precipitation - rain(refers to convective precipitation). This phenomenon is formed under the influence of the radiant energy of the Sun, which heats the moisture located on the surface of the Earth, and evaporates it.

Finding into the upper layers of the atmosphere, which are noticeably colder, water is condensed, forming a cluster of the smallest drops. As soon as the amount of condensate reaches a large mass, the water sheds to the ground in the form of plenty of rain.

Types of rain are separated depending on the size of the drops, which, in turn, is associated with streams and air temperature.

The rain variety is formed so - if the air is warm, then it forms larger drops, and if it is cold, then you can observe a drizzling rain (supercheden rain). When dropping the temperature drops rain with snow.

Another related to condensation process is dew drop. This physical phenomenon is based on the fact that in a certain amount of air there may be a strictly defined amount of steam at a given temperature.

While the limit volume of steam is not achieved, the condensation does not occur, but as soon as the number exceeds the desired value, there is a loss in the liquid state of excess. This we can observe in the early morning on the street, looking at the dew, flowers and other solid items.

Another common view of precipitation is snow. It is fundamentally, its formation is similar to the formation of rain, however, it is distinguished by rain from snow in that when falling to the ground, the drops are significantly cooled with air jets, which have a negative temperature, and the formation of microscopic ice crystals.

Since the process of the formation of snowflakes occurs in the air and under the influence of different temperatures, it causes a large number of forms and snowflake crystals.

If the temperature is very low, it is formed by the covered snow, if closer to zero, then storm snow. Wet snow is formed at a temperature of slightly above zero.

One of the dangerous atmospheric phenomena is grad. His formation occurs mainly in the summer, when the heated air flows are carried away by a vapor moisture in the upper layers of the atmosphere, where, overcooked, water freezes, forming ice pieces.

They do not have time to melt when flying to the earth's surface and are often the cause of the destruction of harvest or damage to buildings.

Condensation of water from steam is possible in winter. Basically, this is due to a very low indicator of relative humidity.

At the same time, given the negative temperature, the moisture condensed the moisture immediately freezes on solid surfaces, forming an air.

Types of precipitation by season

Often use a characteristic based on seasonality precipitation.

So, there are:

• precipitation falling predominantly in the warm season - Rain, moro (rain subtype), dew, hail;
• precipitation whose loss takes place in the cold season - Snow, cereals (subspecies of snow), frost, hoarflash, ice.

Types of precipitation in the height of education

A more accurate classification, which takes into account, at what height there was a conversion of condensate into one of the types of precipitation:

• to sediments that are formed in the upper and middle layers of the atmosphere include rain, moro, hail, cereal and snow - dropping out of the clouds;
• the sediments that are formed in the immediate vicinity of the earth's surface (orographic precipitation) include mainly condensing phenomena (examples - dew, frost, hoarflash and ice) - dropping out of the air.

How precipitation is measured

Often, in the weather forecast, you can hear that 2 millimeters of precipitation fell during the day. Such data meteorologists and weather forecasters are determined by meteorological stations with special equipment - sediment meters.

These are graduated buckets (which are applied conditional signs), performed in a specific sizes that are installed on the street.

Daily, in the time of time from 9-00 to 21-00 (time is taken on the GMT 0 time zone), the meteorologist collects all the moisture, which accumulates in the bucket, and transfers to a measuring cylinder (cylinder divisions are made in mm).

The obtained values \u200b\u200bare recorded in the registration log, forming a precipitation table. If the precipitation dropped was solid, then it is allowed to melt them.

To build a visual picture, the map indicates points with a measured amount of precipitation. These points are connected in the circuit lines - is bellows, and the space paints the colors with increasing intensity.

How precipitation affects the work of aviation

There are a number of very important atmospheric factors that make it difficult to work aviation. First of all, it is associated with safety safety.

The main ones are:

1. First of all, it is a deterioration of visibility for aircraft pilots. A decrease in visibility to heavy rain or a snowy storm takes up to 1.5-2 km, which makes it difficult to visual courses.
2. When taken over or landing, the condensation of moisture on the glasses or optical reflectors can lead to a distorted perception of information by the pilot.
3. A large amount of water fine dust when entering the engine may make it difficult and disrupt its work.
4. In the icing of aerodynamic elements of the aircraft (wings, steering elements), a loss of flight characteristics occurs.
5. When dropping significantly, the amount of precipitation makes it difficult to contact the runway coating.

Thus, all the sediments, in relation to aviation, are exceptionally unfavorable.

The precipitation is a key factor contributing to the formation on the land of climate, as well as geographical zones. The conditional separation is carried out depending on seasonality, however, it should be remembered that combinations can occur in the offseason. Also precipitation is an essential element of water turnover on the planet.

Atmospheric precipitates call water in a liquid and solid state, which falls out of the clouds and deposits from the air

Views of atmospheric oyphans

For atmospheric precipitation, there are different classifications. There are plated precipitates that are associated with warm fronts and storm sediments that belong to the cold fronts.

Measure precipitates in millimeters - the thickness of the water layer. On average, in high latitudes and deserts falls about 250 mm per year, and in general on the globe about 1000 mm of precipitation per year.

The measurement of precipitation is extremely important for any geographic studies. After all, precipitation is one of the most important links of moisture-turn on the globe.

The determining characteristics for a particular climate are the average monthly, annual, seasonal and perennial amount of precipitation, their daily and annual move, their repeatability and intensity.

These indicators are extremely important for the majority of the folk (rural) economy.

Rain is a liquid precipitate - in the form of drops from 0.4 to 5-6 mm. Rain drops can leave a trace in the form of a wet spot on a dry subject, on the surface of the water - in the form of a diverging circle.

There are different types of rain: ice, supercooled and rain with snow. And the overcooked rain and ice fall out at a negative air temperature.

For supercooled rain, liquid precipitation is characteristic, the diameter of which reaches 5 mm; After this type of rain can form ice.

And ice rain is represented in solid state - these are ice balls, inside which there is frozen water. Snow is called precipitation, which fall out in the form of flakes and snow crystals.

Horizontal visibility depends on the intensity of snow dropping. Distinguish sleet and rain with snow.

Weather concept and its features

The state of the atmosphere in a particular place is called the weather at a specific time. Weather - the most volatile phenomenon in the environment. It will start raining, then the wind, and a few hours later the sun will shine and the wind subsides.

But even in the changeability of the weather there are its own patterns, despite the fact that the formation of weather affects a huge number of factors.

The main elements characterizing the weather can be called such meteorological indicators: solar radiation, atmospheric pressure, air humidity and temperature, precipitation and wind direction, wind strength and cloudiness.

If we talk about the changeability of weather, then most often it changes in moderate latitudes - in regions with a continental climate. And the most sustainable weather happens in polar and equatorial latitudes.

The change in the weather is related to the change of season, that is, changes have a periodic character, and over time, weather conditions are repeated.

Every day we are watching the daily change of weather - the night replaces the day, and for this reason, weather conditions change.

Climate concept

Perennial weather regime is called climate. The climate is determined in a particular area - thus, the weather mode must be resistant for a certain geographic location.

Recently in different parts The globe increasingly arise problems associated with the number and nature of precipitation. This year in Ukraine there was a very snowy winter, but at the same time an unprecedented drought was observed in Australia. How are atmospheric precipitation arise? What depends on the nature of the fallout and many other issues are currently relevant and important. Therefore, I chose the topic of your work "Education and types of atmospheric precipitation".

Thus, the main objective of this work is to study the formation and types of precipitation.

The following tasks are allocated during the work:

• · Determination of the concept of atmospheric precipitation
• · Study existing species atmospheric oyphans
• · Consideration of the problem and consequences of the loss of acid rain.

The main method of research in this paper is the method of research and analysis of literary sources.

Atmospheric precipitation (Greek. Atmos - couples and Russian. To deposit - fall to the ground) - water in liquid (moro, rain) and solid (cereal, snow, hail), falling out of the clouds as a result of steam condensation rising in Mainly with the oceans and seas (evaporated water from land is about 10% of atmospheric precipitation). The atmospheric precipitation also includes frost, frost, dew, besieged on the surface of ground items when condensation of vapors in a saturated moisture air. Atmospheric precipitation - the link of the general moisture revolution of the Earth. At the occurrence of the warm front, contemporary and frosting rains are common, and when cold - storm. Atmospheric precipitates are measured using a sedimentary on meteorological stations of the water layer (in mm), which dropped per day, month, year. The average amount of atmospheric precipitation of the Earth is about 1000 mm / year, but in the deserts there are less than 100 and even 50 mm / year, and in the equatorial zone and on some viewed mountain slopes - up to 12000 mm / year (Charranuja meteorotan at an altitude of 1300 m). Atmospheric precipitation is the main water suppliers to watercourses, in the soil that feed the entire organic world.

The main condition for the formation of atmospheric precipitation is the cooling of warm air, leading to the condensation of the pair contained in it.

When clouded and cooling warm air, clouds consisting of water droplets are formed. Faced in the cloud, drops are connected, their weight increases. The lower part of the cloud shines, and it spills the rain. With negative air temperatures, water drops in the clouds freeze and turn into snowflakes. Snowflakes stick in flakes and fall on the ground. During the snowfall, they can define a little, and then wet snow goes. It happens that air flows are repeatedly lowered and raised frozen drops, at this time the ice layers increase on them. Finally, the drops are becoming hard, which falls to the land of hail. Sometimes gradins reach the size of chicken egg. IN summer time With clear weather, the earth's surface is cooled. Overground air layers are cooled from it. Water steam begins to condense on cold items - leaves, grass, stones. So the dew is formed. If the surface temperature was negative, the water droplets freeze, forming an oh. Rosa usually falls in summer, frost - in spring and autumn. At the same time, the dew, and others can only be formed with clear weather. If the sky is closed with clouds, then the earth surface cools slightly and cannot cool the air.

According to the method of formation, convective, frontal and orographic precipitations are allocated. The general condition for the formation of precipitation is the upward movement of air and its cooling. In the first case, the cause of air lifting is its heating from a warm surface (convection). Such precipitates fall out round year In a hot belt and in the summer time in moderate latitudes. If warm air rises up when interacting with colder air, the front precipitates are formed. They are more inherent in moderate and cold belts, where warm and cold air masses are more common. The cause of the rise of warm air may be his collision with the mountains. In this case, orographic precipitation is formed. They are characteristic of the windward slopes of the mountains, and the amount of precipitation on the slopes is grely than on the adjacent areas of the plains.

The amount of precipitation fell is measured in millimeters. On average per year on ground surface About 1100 mm of precipitation falls.

Dropping out of the clouds of precipitation: rain, moro, hail, snow, cereals.

Distinguish:

• · Cover precipitates associated mainly with warm fronts;
• · Storm sediments associated with cold fronts. Aerial precipitation: dew, frost, hoarfish, holly. The precipitate is measured by the thickness of the water dropping layer in millimeters. On average, about 1000 mm of precipitation falls on the globe, and in the deserts and in high latitudes - less than 250 mm per year.

The measurement of precipitation is performed by rainers, sediments, pluvographs on meteorological stations, and for large areas - with the help of radar.

Perennial, average monthly, seasonal, annual precipitation, their distribution for the earth's surface, annual and daily move, repeatability, intensity are the defining characteristics of the climate that are essential for agriculture and many other sectors of the national economy.

The greatest amount of precipitation on the globe should be expected where the atmospheric humidity is large and where there are conditions for raising and cooling the air. The amount of precipitation depends: 1) from latitude, 2) on the total circulation of the atmosphere and the processes associated with it, 3) from the relief.

The greatest amount of precipitation and on land and the sea falls near the equator, in the belt between 10 ° C. sh. and 10 ° sh. Next to the north and to the south, the amount of precipitation decreases in the field of trade winds, and the rainfall minima is more or less coincided with subtropical pressure maxima. At sea, rainfall is closer to the equator than on land. However, the numbers illustrating the amount of precipitation to the sea are not particularly trusted in view of the insignificant number of observations.

From subtropical maxima of pressure and low-rise minima, the number of these latter recently increases and reaches a second maximum in approximately 40-50 ° latitudes, and hence the poles.

A large amount of precipitation under the equator is explained by the fact that the region is created here as a result of thermal reasons. reduced pressure With ascending currents, air with a large content of water vapor (on average E \u003d 25mm), rising, cooled and condenses moisture. A small amount of precipitation in the field of trade winds is due to these last winds.

The smallest amount of precipitation observed in the field of subtropic pressure maxima is explained by the fact that these areas have a downward movement of air. Air, dropping, heats up and becomes dry. Next to the north and south, we enter the area of \u200b\u200bthe prevailing southwestern and northwestern winds, i.e. Winds moving from warmer countries in colder. Here, in addition, cyclones appear very often, therefore, conditions favorable air raising and its cooling are created. All this entails an increase in precipitation.

As for reducing the amount of precipitation in the polar region, it should be borne in mind that they apply only to the measurable rain, snow, the cereal, but not taken into account the deposition of the Inea; Meanwhile, it is necessary to assume that the education of Ineu in the Polar Countries, where due to low temperatures relative humidity Very large, occurs in large quantities. Indeed, some polar travelers observed that condensation takes place here preferably from the lower, in contact with the surface, the air layers in the form of an inlet or ice needles deposited on the surface of snow and ice and significantly increasing their power.

A huge effect on the amount of drop-down moisture has relief. Mountains, forcing air to rise, determine its cooling and condensation of vapors.

You can especially clearly trace the dependence of the amount of precipitation from the height in such settlements, which are located on the slopes of the mountains, and the lower quarters are located at the sea level, and the upper, are pretty high. Indeed, in each locality, depending on the entire set of meteorological conditions, there is a certain zone, or the height on which the maximum condensation of vapors occurs, and above this area, the air becomes more dry. Thus, on the Mont Blanc zone of the greatest condensation lies at an altitude of 2600 m, in the Himalayas on the southern slope - on average at an altitude of 2400 m, in the Pamir and Tibet - at an altitude of 4500 m. Even in the mountain sugar, moisture condenses.

By the time of falling out of the maximum amount of precipitation, all countries can be divided into two categories: 1) countries with prevailing summer and 2) countries with prevailing winter sediments. The first category includes a tropical region, more continental regions of moderate latitudes and northern outskirts of the sushi of the northern hemisphere. Winter precipitations prevail in sub tropical countries, then the pace of oceans and seas, as well as in countries with marine climates in moderate latitudes. In the winter of the oceans and the sea, warmer than dry, pressure decreases, favorable conditions are created for the occurrence of cyclones and precipitation. We can install the following divisions on the globe on the basis of the distribution of precipitation.

Views of atmospheric precipitation. Grad - they are called a special kind of ice formations, which sometimes fall out of the atmosphere and ranked with atmospheric precipitation, otherwise hydrometeors. The view, structure and dimensions of the gradin are extremely diverse. One of the most ordinary forms is a conical or pyramidal with sharp or slightly truncated tops and rounded base. The upper part of such commonly softer, matte, as if snow; The average - translucent, consisting of concentric, alternating between the transparent and opaque layers; Lower, the largest - transparent.

No less often occurs a spherical form consisting of an inner snow nucleus (sometimes, although less often, the central part consists of transparent ice), surrounded by one or more transparent shells. The duration of the hail is accompanied by a special characteristic noise from the gradin stroke, resembling a noise derived from the rash of nuts. The hail falls the greatest part in the summer and day. Hilarity at night - the phenomenon is very rare. Lasts a few minutes, usually less than a quarter of an hour; But there are cases when it lasts more. The distribution of hail on Earth depends on the latitude, but mainly from local conditions. In tropical countries, Hrad - the phenomenon is very rare, and it falls there almost only in high plateales and mountains.

Rain - liquid precipitation in the form of drops with a diameter of 0.5 to 5 mm. Separate rain drops are left on the surface of the water a trail in the form of a diverging circle, and on the surface of dry items - in the form of a wet spot.

Imcoolent rain - liquid precipitations in the form of drops with a diameter of 0.5 to 5 mm, dropping down at a negative air temperature (most often 0 ... -10 °, sometimes up to -15 °) - falling on items, droplets are fatal and ice is formed. The supercooled rain is formed when the falling snowflakes fall into the layer of warm air, deep enough so that the snowflakes completely melted and turned into a drip of the rain. As these droplets continue to fall, they pass a thin layer of cold air above the ground surface and their temperature becomes below the freezing temperature. However, the drops themselves do not freeze, so this phenomenon called the hypadation (or the formation of "supercooled drops").

Ice rain - solid precipitates dropping under negative air temperature (most often 0 ... -10 °, sometimes up to -15 °) in the form of solid transparent ice balls with a diameter of 1-3 mm. It is formed during freezing of rain drops when they fall through the lower layer of air with a negative temperature. Inside the balls there is unlocked water - falling on the items, the balls are broken down on the shells, the water flows and the ice is formed. Snow - solid precipitation dropping (most often under negative air temperature) in the form of snow crystals (snowflakes) or flakes. With weak snow, horizontal visibility (if there are no other phenomena - haze, fog, etc.) is 4-10 km, with a moderate 1-3 km, with high snow - less than 1000 m (at the same time, the strengthess of the snow occurs gradually, So the values \u200b\u200bof visibility are 1-2 km and less observed no earlier than an hour after the start of the snowfall). In frost weather (air temperature below -10 ... -15 °), weak snow can fall out of the stiffness. Separately there is a phenomenon of wet snow - mixed precipitates falling down at a positive air temperature in the form of melting snow flakes. Rain with snow - mixed precipitation dropping (most often with positive air temperature) in the form of a mixture of drops and snowflakes. If the rain with snow falls down under a negative air temperature, the precipitation particles merge on the items and the ice is formed.

Moros - liquid precipitation in the form of very small drops (with a diameter of less than 0.5 mm), as if soaring in the air. Dry surface wet slowly and evenly. Hosted on the surface of the water does not forms diverging circles on it.

The fog is the accumulation of condensation products (droplets or crystals, or those and others together) weighted in the air, directly above the surface of the Earth. Perusting air caused by such a cluster. Usually these two values \u200b\u200bof the word fog do not differ. With fog, horizontal visibility is less than 1 km. Otherwise, the cloudiness is called a haze.

Shower - short-term precipitation, usually in the form of rain (sometimes wet snow, cereals), characterized by a large intensity (up to 100 mm / h). Arise in unstable air masses on a cold front or as a result of convection. Typically, the rain rain covers a relatively small territory. Storm snow - snowproof snow. It is characterized by sharp fluctuations in horizontal visibility from 6-10 km to 2-4 km (and sometimes up to 500--1000 m, in some cases even 100--200 m) for a period of time from a few minutes before half an hour (snow "charges") . Snowy croup - severe rainfall precipitations dropping at the air temperature near zero ° and having a form of opaque white grains with a diameter of 2-5 mm; Crupins are fragile, easily crushed with fingers. It is often falling in front of a storm snow or simultaneously with it. Ice cereals - severe rainfall precipitations, falling down at air temperature from +5 to + 10 ° in the form of transparent (or translucent) ice grains with a diameter of 1-3 mm; In the center of Crupina - an opaque kernel. Crupins are solid (crushed with some effort), when falling on a solid surface, bounce. In some cases, grapplets can be covered with water film (or falling along with water droplets), and if the air temperature is below zero °, then falling on the items, the grains are fatal and ice is formed.

Rosa (Lat. ROS - moisture, liquid) - a atmospheric precipitate in the form of water droplets deposited on the surface of the Earth and ground items when air cooling.

Morning - loose ice crystals increasing on the branches of trees, wires and other objects usually with the lunch of droplets of the supercourse fog. It is formed in winter, more often in quiet frosty weather as a result of sublimation of water vapor with a decrease in air temperature.

Ana is a thin layer of ice crystals that are generated in cold, clear and quiet nights on the surface of the earth, herbs and objects with a negative temperature, and lower than air temperature. Inea crystals in the same way as the frost crystals are formed by sublimation of the water vapor.

For the first time, acid rains were marked in Western Europe, in particular Scandinavia, and North America in the 1950s. Now this problem exists in the entire industrial world and has gained special importance due to the increased technogenic emissions of sulfur and nitrogen oxides. Atmospheric precipitate Acid rain

When the power plant I. industrial enterprises Ground coal and oil, with their chimneys, there are huge amounts of sulfur dioxide, suspended particles and nitrogen oxides. In the United States on power plants and factories, it is from 90 to 95% of sulfur dioxide emissions. and 57% of nitrogen oxides, and almost 60% of sulfur dioxide is ejected to high pipes, which facilitates their transfer over long distances.

As the dilation of sulfur dioxide and nitrogen oxide from stationary sources are transferred to the wind over long distances, the secondary contaminants are formed, such as nitrogen dioxide, nitric acid pairs and droplets containing sulfuric acid solutions, sulphate and nitrate salts. These chemicals fall on the earth's surface in the form of acid rain or snow, and also in the form of gases, pellens, dews or solid particles. These gases can directly absorb foliage. The combination of dry and wet ospios and absorption of acids and acid-forming substances with a close surface of the earth's surface or are called acid precipitation, or acidic rain. Another reasons for acid precipitation are nitrogen oxide discharges in large numbers of cars in large cities. This type of pollution is a danger as for urban, and for rural areas. After all, water drops and most solid particles will soon be removed from the atmosphere, acid precipitates are more likely regional or continental than a global problem.

The consequences of the loss of acid rain:

• · Damage to statues, buildings, metals and car finishes.
• · Loss of fish, aquatic plants and microorganisms in lakes and rivers.
• · Weakening or loss of trees, especially coniferous rocks that grow at large altitudes, due to leaching from the soil of calcium, sodium and other nutrients damage to the roots of trees and the loss of numerous species of fish due to exemption from soils and dairy precipitation of aluminum ions, lead, mercury and cadmium
• · Weakening trees and strengthening their tendency to disease, insects, droughts, mushrooms and MCHAM, which bloom in an acidic environment.
• · Slowing growth of cultivated plants, such as tomatoes, soybeans, beans, tobacco, spinach, carrots, cabbage broccoli and cotton.

Acid precipitation is already a serious problem in Northern and Central Europe, in the north-east of the United States, in Southeast Canada, in some areas of China, Brazil and Nigeria. Even a big threat, they begin to submit in the industrial regions of Asia, Latin America and Africa and in some places in the West of the United States (mainly due to dry precipitation). Acid precipitation falls out and in the ranps of tropical areas, where industry is practical, mainly due to the release of nitrogen oxides during biomass burning. Most of the acid-forming substances produced by aquatic country are transferred to the premiest surface winds into the territory of the other. More than three-quarters of acid precipitation in Norway, Switzerland, Austria, Sweden, the Netherlands and Finland are brought to these countries with wind from industrial areas of Western and Eastern Europe.

List of used literature

• 1. Akimova, T. A., Kuzmin A. P., Khaskin V. V., Ecology. Nature - Man - Technique: Textbook for universities. - M.: Uniti - Dana, 2001.- 343c.
• 2. Vronsky, V. A. Acid rain: Ecological aspect // Biology in school. - 2006.- №3.- with. 3-6
• 3. Isaev, A. A. Environmental climatology. - 2nd ed. Spread. and additional. - M.: Scientific World, 2003.- 470c.
• 5. Nikolaikin, N. I., Nikolaikin N. E., Melekhova O. P. Ecology. - 3rd ed. Pererab. and add-m.: Drop, 2004.- 624c.
• 6. Novikov, Yu. V. Ecology, environment, Man: Tutorial. - M.: Grand: Fair - Press, 2000.- 316c.

Evaporation of water vapor, its transfer and condensation in the atmosphere, the formation of clouds and precipitation is a single complex climatic the process of moisture - company, As a result of which a continuous transition of water from the earth's surface occurs in the air and from the air again to the earth's surface. The precipitate are the most important component of this process; It is them, along with the air temperature, belongs to the decisive role among those phenomena that are combined with the concept of "weather".

Atmospheric precipitation It is called moisture that dropped on the surface of the Earth from the atmosphere. Atmospheric precipitates are characterized by an average number for the year, season, a separate month or day. The amount of precipitation is determined by the height of the water layer in the MM, which formed on the horizontal surface from the dropped rain, frost, abundant dew and fog, which melted snow, nasta, hail and snowy cereals in the absence of seeping into the ground, surface drain and evaporation.

Atmospheric precipitates are divided into two main groups: dropping out of the clouds - rain, snow, hail, cereals, moro, etc.; Formed on the surface of the Earth and on items - dew, frost, frost, ice.

The sediments of the first group are directly related to another atmospheric phenomenon - cloud which plays an essential role in the temporary and spatial distribution of all meteorological elements. Thus, the clouds reflect straight solar radiation, reducing its arrival to the earth's surface and changing the conditions of illumination. At the same time, they increase scattered radiation and reduce efficient radiation, which contributes to an increase in absorbed radiation.

Changing the radiation and thermal mode of the atmosphere, the clouds have a great effect on floral and animal world, as well as for many parties to human activity. From an architectural and building point of view, the role of clouds is manifested, firstly, in the amount of total solar radiation coming to the territory of development, to buildings and structures and the determining thermal balance and the mode of natural illumination of the inner medium. Secondly, the phenomenon of cloudiness is associated with the fallout of precipitation, which determine the humidity regime of the operation of buildings and structures affecting the thermal conductivity of the enclosing structures, their durability, etc. Thirdly, the loss of solid precipitation from the cloud determines the snow loads on the buildings, and hence the shape and construction of the roof and other architectural and typological featuresassociated with snow cover. Thus, before proceeding with precipitation, it is necessary to dwell in more detail on such a phenomenon as cloudy.

Clouds - These are clusters of condensation products (droplets and crystals) visible to a simple eye. By the phase state of cloud elements, they are divided into water (drip) - consisting only of drops; icy (crystalline) - consisting only of ice crystals, and mixed - consisting of a mixture of supercooled droplets and ice crystals.

Forms of clouds in the troposphere are very diverse, but they can be reduced to a relatively small number of basic types. Such a "morphological" classification of clouds (i.e., classification according to their appearance) originated in the XIX century. And is generally accepted. According to it, all the clouds are divided into 10 main births.

Three tiers of clouds are distinguished in the troposphere: upper, medium and lower. Bases of clouds upper Yarusa located in polar latitudes at altitudes from 3 to 8 km, in moderate latitudes - from 6 to 13 km and in tropical latitudes - from 6 to 18 km; middle Yarusa respectively - from 2 to 4 km, from 2 to 7 km and from 2 to 8 km; nizhny Yarusa All latitudes - from the earth's surface up to 2 km. Clouds of the upper tier include pirish, peristo-cochess and peristo-layered. They consist of ice crystals, translucent and shortly shadow sunlight. In the middle tier are located high-cocked (drip) and high-layered (mixed) clouds. In the lower tier are present layered, layman and layered-cochess Clouds. Layered rain clouds consist of a mixture of drops and crystals, the rest are drip. In addition to these eight main types of clouds, there are two more, the grounds of which are almost always in the lower tier, and the peaks penetrate the middle and the upper tier - this kuchny (drip) and kuchevo-rain (mixed) clouds called vertical development clouds.

The degree of covering the clouds of the celestial and is called cloudiness. Basically, it is determined by the "on the eye" by the observer on meteorological stations and is expressed in points from 0 to 10. At the same time, the level of not only general, but also the lower clouds, to which the clouds of vertical development are also set. Thus, cloudy is recorded in the form of a fraction, in the numerator of which there is a general clue, in the denominator - the bottom.

Along with this, clouds are determined by photographs obtained from artificial satellites of the Earth. Since these photos are made not only in the visible, but also the infrared range, it is possible to evaluate the number of clouds not only during the day, but at night, when terrestrial observations are not conducted. A comparison of terrestrial and satellite data demonstrates their good consistency, while the greatest differences are observed on the continents and make up approximately 1 point. Here, ground measurements due to subjective reasons are somewhat overlapping the number of clouds compared to satellite data.

Summing up the perennial observations for the cloudiness, the following conclusions can be drawn relative to its geographical distribution: on average, cloudiness is 6 points for the whole globe, and it is greater than above the continent. The number of clouds is relatively small in high latitudes (especially in the southern hemisphere), with a decrease in latitude it grows and reaches a maximum (about 7 points) in the belt from 60 to 70 °, then cloudy decreases to 2-4 points and is growing again With the approach to the equator.

In fig. 1.47 shows a common cloud score on average for the year for the territory of Russia. As can be seen from this pattern, the number of clouds in Russia is distributed rather unevenly. The most cloudy are the north-west of the European part of Russia, where the amount of total cloudiness on average per year is 7 points and more, as well as the coast of Kamchatka, Sakhalin, the north-west coast of the Sea of \u200b\u200bOkhotsk, Kuril and Commander Islands. These areas are located in areas of active cyclonic activities characterized by the most intense atmospheric circulation.

Eastern Siberia, except for the Middle Bicarian Plateau, Transbaikalia and Altai, is characterized by a smaller average annual cloud. Here it is ranging from 5 to 6 points, and in the extreme south there are even less than 5 points. All this relatively, the most relaxed area of \u200b\u200bthe Asian part of Russia is in the influence of the Asian Anticyclone, therefore, it is characterized by a small repeatability of cyclones, with which a large number of clouds are mainly connected. A strip of a less significant amount of clouds is also distinguished, elongated in the meridional direction directly behind the Urals, which is explained by the "shadowing" role of these mountains.

Fig. 1.47.

Under certain conditions from clouds fall out precipitation. This happens when part of the elements that make up the cloud is enlarged and can no longer be held by vertical air currents. The main and necessary condition for the fallout of heavy precipitation is the simultaneous presence in the cloud of undercooled droplets and ice crystals. These are precisely the high-layered, layered-rain and cumulating clouds, from which precipitation falls out.

All sediments are divided into liquid and solid. Liquid precipitation - It is rain and moro, they differ in the size of the drop. TO solid precipitation Snow, wet snow, cereals and hail. The amount of precipitation is measured in mm layer of water dropping. 1 mM precipitation corresponds to 1 kg of water that dropped on the square in 1 m 2, provided that it does not flow, it does not evaporate and does not absorb soil.

By the nature of precipitation, the following types are divided into the following types: cover precipitation - Uniform, long-term duration, fall out of layered rain clouds; storm sediments - Characterized by a rapid change in intensity and short-term, they fall out of the heap clouds in the form of rain, often with a hail; heavy precipitation - In the form of MOSI drop out of layered rain clouds.

The daily move of the draft It is very complicated, and even in perennial averages in it, it is often impossible to detect any pattern. Nevertheless, two types are distinguished daily move precipitation - continental and nautical (coastal). The continental type has two maxima (in the morning and afternoon) and two minima (at night and before afternoon). Sea type is characterized by one maximum (at night) and one minimum (day).

The annual movement of precipitation is bottled on different latitudes and even within the same zone. It depends on the amount of heat, the thermal regime, air circulation, the remoteness from the coast, the nature of the relief.

The most abundant precipitation in equatorial latitudes, where their annual number exceeds 1000-2000 mm. On the Equatorial Islands of the Pacific Ocean drops 4000-5000 mm, and on the winding slopes of tropical islands - up to 10,000 mm. The cause of abundant precipitation is powerful ascending currents wet air. To the north and south of equatorial latitudes, the rainfall decreases, reaching a minimum on latitudes 25-35 °, where the average annual value does not exceed 500 mm and decreases in intra-engineity areas up to 100 mm and less. In moderate latitudes, the amount of precipitation increases slightly (800 mm), rebounding to high latitudes.

The maximum annual precipitation is registered with Cher Rapundezhi (India) - 26,461 mm. The minimum marked annual rainfall is in Aswan (Egypt), ICIK - (Chile), where in some years the precipitation does not fall at all.

By origin, convective, frontal and orographic precipitation distinguish. Convective precipitation Characteristic for a hot belt, where intense heating and evaporation, but in the summer there are often in a temperate belt. Front preciputes are formed at a meeting of two air masses with different temperatures and other physical properties. Genetically, they are associated with cyclonic vortices typical of internal latitudes. Orographic precipitation falls out on the windy slopes of the mountains, especially high. They are abundant if the air comes from the warm sea and has a large absolute and relative humidity.

Measurement methods. The following devices are applied to collect and measure precipitation: Tretyakov's settlement, total ozide commeris and plvirograph.

Sediment Tretyakova It serves to collect and subsequent measurement of the amount of liquid and solid precipitation, which dropped over a certain period of time. It consists of a cylindrical vessel with a reception area of \u200b\u200b200 cm 2, a plank cone-shaped protection and tagan (Fig. 1.48). The kit also includes a spare vessel and cover.

Fig. 1.48.

Reception vessel 1 It is a bucket of a cylindrical shape, bombing aperture 2 In the form of a truncated cone, in which in summer, a funnel with a small hole in the center is inserted in the summer to reduce the evaporation of precipitation. To drain the liquid in the vessel there is nozzle 3, Closed cap 4, soldered on a chain 5 to a vessel. Vessel installed on tagan 6, surrounded by cone-shaped plank protection 7 consisting of 16 curved plates on a special template. This defense is necessary to prevent snow from a snow sedimentary in winter and rain drops with a strong wind in the summer.

The amount of precipitation treated for the night and day half of the day is measured in the deadlines, coming to 8 and 20 hours of waist decret (winter) time. In time 03 and 15 h UTC. Universal Time Coordinated - World Coordinated Time) In I and II time zones, the main stations also measure precipitation over an additional settlement, which must be installed on the weather cutoff. For example, in the meteorological service of Moscow State University, the sediments are measured at 6, 9, 18 and 21 h at the rendering time. For this, the measuring bucket, having previously closed with the lid, carries into the room and through the spout water into a special measuring glass. To each measured amount of precipitation, an adjustment for wetting a sedimentation vessel is added, which is 0.1 mm, if the water level is lower than half of the first division, and 0.2 mm, if the water level in the middle of the first division or higher in the measuring cup.

Solid precipitates collected in a precipitated vessel must be melted before measuring. For this, the sediment vessel is left in the warm room for a while. The vessel should be closed with a lid, and the nose-cap to avoid evaporation of precipitation and deposition of moisture on the cold walls on the inside of the vessel. After the solid precipitation is melted, they are transferred to a sedimentary glass for measurement.

In non-heated, hard-to-reach areas applied summer settlement M-70, Designed for collecting and subsequent measurement of precipitation dropped over a long period of time (up to a year). This sediment is consisting of a receiving vessel. 1 , reservoir (precipitation collection) 2, Basis 3 and protection 4 (Fig. 1.49).

The reception area of \u200b\u200bthe sedimentary is 500 cm 2. The tank consists of two detachable parts having a cone shape. For a more dense connection of the parts of the tank between them, the rubber gasket is inserted. Received vessel reinforced in the reservoir hole

Fig. 1.49.

on the flange. The tank with the receiving vessel is attached on a special base, which consists of three racks connected by means of spacer. Protection (from blowing up precipitation) consists of six plates that are attached to the base through two rings with clamping nuts. The top edge of protection is in one horizontal plane with the edge of the receiving vessel.

To prevent precipitation from evaporation into the tank at the installation site, mineral oil is poured. It is lighter than water and forms a film that prevents them with evaporation on the surface of the accumulated precipitation.

Liquid precipitates are chosen using a rubber pear with a tip, solid - carefully split and choose a pure metal mesh or blade. The determination of the amount of liquid precipitation is produced using a measuring glass, and solid - by weight.

To automatically register the amount and intensity of liquid atmospheric precipitation pluviograph (Fig. 1.50).

Fig. 1.50.

The pluviograph consists of a housing, a float chamber, a mechanism forced drain and siphon. The precipitation receiver is a cylindrical vessel / with a 500 cm reception room 2. It has a bottom cone-shaped form with water drain holes and strengthened on a cylindrical case. 2. Sedimes through drain tubes 3 and 4 fall into the recording device consisting of a float chamber 5, inside which is moving float 6. On the rod float, the arrow 7 is fixed with a pen. The recording of precipitation is made on the tape, put on the clock mechanism drum 13. A glass siphon 9 is inserted into the metal tube 8, through which water from the float chamber merges into the control vessel 10. Metal sleeve is bent on the siphon 11 With clamping coupling 12.

With the flow of precipitation from the receiver in the float chamber, the water level in it increases. At the same time, the float rises up, and the feather draws the curve line on the tape - the more cool, the greater the intensity of precipitation. When the amount of precipitation reaches 10 mm, the water level in the siphon tube and the float chamber becomes the same, and there is a spontaneous draining of water in a bucket 10. At the same time, the feather draws the tape vertical straight line from top to bottom to zero mark; In the absence of precipitation, the feather draws a horizontal line.

Characteristic values \u200b\u200bof precipitation. For the characteristic of the climate, average quantities are calculated or amounts of Ospalkov During certain intervals - month, year, etc. It should be noted that the formation of precipitation and their number on any territory depend on the three main conditions: moisture content aerial mass, its temperatures and ascent options (lifting). These conditions are interconnected and, acting together, create a rather complex picture of the geographical distribution of precipitation. Nevertheless, analysis climatic maps Allows the most important patterns of precipitation fields.

In fig. 1.51 shows the average perennial amount of precipitation falling over the year in Russia. From the drawing it follows that in the territory of the Russian plain the greatest number The precipitation (600-700 mm / year) falls in a band 50-65 ° C.Sh. It is here that cyclonic processes are actively developing throughout the year and the greatest amount of moisture from the Atlantic is being transferred. To the north and south of this zone, the amount of precipitation decreases, and the south of 50 ° S.Sh. This decrease occurs from the North-West to the southeast. So, if 520-580 mm / year falls on the Oksk-Donskaya Plain, then in the lower flow of p. Volga This amount decreases to 200-350 mm.

The Ural substantially transforms the field of precipitation, creating a meridionally elongated strip of elevated amounts on the windward side and on the vertices. At some distance behind the ridge, on the contrary, there is a decrease in the annual amount of precipitation.

Similar to the latal distribution of precipitation in the Russian plain on the territory of Western Siberia in a strip 60-65 ° C.Sh. There is a zone of an increased amount of precipitation, however, it is already in the European part, and precipitation here falls less. For example, in the middle course p. Obi Annual precipitation is 550-600 mm, decreasing to the Arctic coast up to 300-350 mm. Almost the same precipitation falls in the south of Western Siberia. At the same time, compared to the Russian plain, the area of \u200b\u200bsmall precipitation here is significantly shifted to the north.

As it moves to the east, in the maintenance of the continent, the amount of precipitation decreases, and in the extensive basin located in the center of the Central Lowland, a closed medium-protein plate from the Western winds, the amount of precipitation is only 250-300 mm, which is characteristic of steppe and semi-desert areas of more southern lard. Further east, as you approach the outskin seas of the Pacific Ocean, the amount

Fig. 1.51.

the precipitation increases sharply, although complex relief, various orientation of the mountain ranges and slopes create a noticeable spatial heterogeneity in the distribution of precipitation.

Impact of precipitation on various sides economic activity A person is expressed not only in a more or less strong moistening of the territory, but also in the distribution of precipitation throughout the year. For example, severe subtropical forests and shrubs grow in areas where the annual amount of precipitation is 600 mm, and this amount falls over three winter months. The same amount of precipitation, but distributed evenly during the year, determines the existence of a zone of mixed forests of moderate latitudes. Many hydrological processes are also associated with the nature of the intransigence distribution of precipitation.

From this point of view, the ratio of precipitation in the cold period is served from this point of view to the amount of precipitation during the warm period. In the European part of Russia, this ratio is 0.45-0.55; in Western Siberia - 0.25-0.45; In Eastern Siberia - 0.15-0.35. The minimum value is noted in Transbaikalia (0.1), where the effect of Asian anticyclone is most expressed in winter. At the Sakhalin and the Kuril Islands, the ratio is 0.30-0.60; The maximum value (0.7-1.0) is marked in the east of Kamchatka, as well as in the mountain arrays of the Caucasus. The predominance of the amount of precipitation in the cold period over the sediments of the warm period is observed in Russia only on the Black Sea coast of the Caucasus: for example, in Sochi it is 1.02.

For the annual movement of precipitation, people are forced to adapt, building various buildings for themselves. The most vividly regional architectural and climatic features (architectural and climatic regionalism) are manifested in the architecture of the folk dwellings, which will be said below (see paragraph 2.2).

Effect of relief and buildings on precipitation mode. The relief contributes the most significant contribution to the nature of the field of precipitation. Their amount depends on the height of the slopes, their orientation relative to the moisture reference, horizontal size of the elevations and the general conditions of moisturizing the area. Obviously, in mountain ranges, the slope focused in the direction of the moisture-mounted flow (wind-sleeve), irrigates more than the protected from the wind (leveled slope). On the distribution of precipitation in the plain area, elements of the relief with relative heights of more than 50 m can be influenced, while three characteristic areas are created with a different pattern of precipitation:

• the increase in precipitation on the plain before the elevation (precipitation of "damage");
• the increase in precipitation on the elevation itself;
• Reducing precipitation with ledged side of the hill ("rain shadow").

The first two types of precipitation are called orographic (Fig. 1.52), i.e. Directly related to the effect of terrain (orography). The third type of precipitation distribution is associated with the relief indirectly: decrease in precipitation occurs due to the total reduction in air moisture content, which occurred in the first two situations. Quantitative to the decrease in precipitation in the "rain shadow" is commensurate with an increase in their elevation; The amount of precipitation of "damage" is 1.5-2 times higher than the amount of precipitation in the "rain shadow".

"Projecting"

Windward

Rainy

Fig. 1.52. Scheme of orographic precipitation

Influence of major cities The distribution of precipitation is manifested due to the effect of the "Heat Island" effect, an increased roughness of the urban area and air pollution. Studies conducted in different physico-geographical zones showed that within the city and in the suburbs located on the winding side, the amount of precipitation increases, and the maximum effect is noticeable at a distance of 20-25 km from the city.

In Moscow, the above laws are pronounced quite clearly. The increase in precipitation in the city is observed in all their characteristics, starting with duration and ending with the security of extreme values. For example, the average duration of precipitation (h / months) in the city center (Balchug) exceeds the duration of precipitation on the territory of TSHA as a whole for the year and at any month of the year without exception, and the annual amount of precipitation in the center of Moscow (Balchug) by 10% More than in the near suburb (Nemchinovka), which is most of the time from the windward side of the city. For the purposes of architectural programming analysis, the mesoscale anomaly of the amount of precipitation, which is formed over the territory of the city, is considered as a background to identify smaller-scale patterns, which are mainly in the redistribution of precipitation inside the development.

In addition to the fact that precipitation can fall out of the clouds, they also form on the surface of the earth and on objects. These include dew, frost, frost and ice. Precipitation falling onto the earth's surface and the subjects formed on it are also called atmospheric phenomena.

Dew - Water droplets formed on the surface of the Earth, on plants and objects as a result of comparison of wet air with a colder surface at air temperature above 0 ° C, clear sky and calm or weak wind. As a rule, Rosa is formed at night, but it is possible to appear in the other part of the day. In some cases, Rosa may be observed during the haze or fog. The term "Rosa" is also often used in construction and architecture in relation to those parts of building structures and surfaces in the architectural environment where water vapor can be condensed.

Frost - white precipitate of the crystalline structure appearing on the surface of the Earth and on the subjects (mainly on horizontal or low-chart surfaces). InI appears when cooling the surface of the earth and items due to heat radiation, resulting in a decrease in their temperature to negative values. Animes is formed under a negative air temperature, with a calm or weak wind and a minor cloud. Abundant deposition of the Inea is observed on the grass, the surface of the leaf of shrubs and trees, roofing of buildings and other objects that do not have internal heat sources. Animes may also form on the surface of the wires, causing their weighting and an increase in tension: the thinner the wire, the less Inea is settled on it. On the wires with a thickness of 5 mm, the deposition does not exceed 3 mm. On the threads with a thickness of less than 1 mm, it is not formed; This makes it possible to distinguish between the frost and crystalline frost, the appearance of which are similar.

Frost - White, loose sediment of a crystalline or granular structure, observed on wires, bumps of trees, individual blades and other subjects in frost weather at weak winds.

Grainy frost It is formed due to the meanings on the subjects of supercooled fog droplets. Its increasing is promoted by large wind velocities and the mesmer frost (from -2 to -7 ° C, but sometimes at a lower temperature). Grainy hoarfrost has amorphous (not crystalline) structure. Sometimes the surface is buggy and even needle, but the needles are usually matte, rough, without crystalline faces. Drops of fog in contact with a supercooled object freeze so quickly that they do not have time to lose their shape and give snow-like deposition consisting of ice grains, not distinguished by the eye (icy raid). With increasing air temperature and enlarge the fog droplets to the size of the MOSI, the density of the resulting grainy is frosy increases, and it gradually goes into golwool. With the reinforcement of frost and weakening wind, the density of the resulting grainy frosty decreases, and it gradually replaces the crystalline hoarflash. Deposits of grainy frosts can reach dangerous sizes From the point of view of strength and maintain the integrity of items and structures on which it is formed.

Crystal hoarfrost - White precipitate consisting of fine ice crystals fine structure. When settling on blesses of trees, wires, cables, etc. Crystal hoarfrost has the form of fluffy garlands, easy to creap when shaking. Crystal hoarfrost is formed mainly in the night clouds with a cloudless sky or thin clouds at low air temperature in quiet weather when fog or haze is observed in the air. Under these conditions, the crystals are frozen are formed by direct transition to ice (sublimation) of the water vapor contained in the air. For architectural medium, it is practically non-hazardous.

Goleed Most often occurs when falling and spreading on the surface of large droplets of supercillary rain or sea overlooks in the temperature range from 0 to -3 ° C and is a layer of dense ice increasing mainly from the windward side of the items. Along with the concept of "ice" there is a close concept of "ice". The difference between them is in those processes that lead to ice formation.

Hooleda - This ice on the earth's surface formed after thaw or rain as a result of a cooling occurrence, leading to the freezing of water, as well as during the fallout of rain or wet snow on the lamb.

The impact of ice deposits is varied and, first of all, is associated with the disorganization of the work of energy economy, communications and transport. The radius of ice crusts on the wires can reach 100 mm and more, and the weight is more than 10 kg on the traffic point meter. Such a load is devastable for wired communication lines, power stations, high-altitude masts, etc. For example, in January 1998, the strongest ice storm was swept over the eastern districts of Canada and the United States, as a result of which in five days on the wires, the 10-centimeter layer of ice on the wires, which caused numerous cliffs. About 3 million people remained without electricity, and the total damage amounted to $ 650 million.

In the life of cities, the state of expensive is also very important, which, with illegal phenomena, become dangerous to all types of transport and passersby. In addition, the ice crust inflicts mechanical damage to the designs of buildings - roofing, eaves, scenery of facades. It contributes to the freezing, vanity and death of plants present in the system of gardening cities, and the degradation of natural complexes that are part of the city territory due to lack of oxygen and excess carbon dioxide under the ice shell.

In addition, atmospheric phenomena include electrical, optical and other phenomena, such as fogs, blizzards, dusty storms, megro, thunderstorm, mirage, squalls, whirlwinds, tornadoes and some others. Let us dwell on the most dangerous of these phenomena.

Storm - This complex atmospheric phenomenon necessary is the necessary part of which are multiple electrical discharges between the clouds or between the cloud and land (zipper), accompanied by sound phenomena - thunder. Thunderstorm is associated with the development of powerful cumulating-rain clouds and therefore is usually accompanied by flipper winds and storm sediments, often with a hail. Most often, the thunderstorm and hail are observed in the rear of cyclones at the invasion of cold air when the most favorable conditions for the development of turbulence are created. The thunderstorm of any intensity and duration is most dangerous for the flight of aircraft due to the possibility of defeating their electrical discharges. The electrical overvoltage arising at this time applies to the wires of power lines and distribution devices, creates interference and emergency situations. In addition, the thunderstorms occur active ionization of the air and the formation of an electric field of the atmosphere, which has a physiological effect on living organisms. It is estimated that annually from lightning strikes in the world, an average of 3,000 people die.

From the architectural point of view, the thunderstorm is not very dangerous. Buildings are usually protected from the impact of lightning at the expense of the lightning device (they are often referred to as thunderings), which are devices for grounding electrical discharges and are installed on the most high sites Roof. Rarely there are cases of fire to fire when lightning come into them.

For engineering structures (radio and telemets), the thunderstorm is dangerous mainly because the lightning entrance can fail the radio equipment installed on them.

Grad Called precipitation falling in the form of tight ice particles of the wrong shape of various, sometimes very large sizes. Grad falls, as a rule, in the warm season from powerful cumulating rain clouds. The mass of large gradines is several grams, in exceptional cases - several hundred grams. From the hail suffer mainly green plantings, first of all - trees, especially during flowering. In some cases, gedials acquires the nature of natural disasters. So, in April 1981 in the province of Guangdong, China, grades weighing 7 kg were observed. As a result, five people died and about 10.5 thousand buildings were destroyed. At the same time, by observing with the help of special radar means for the development of domestic foci in cumulating rain clouds and applying methods for active impact on these clouds, approximately 75% of cases can be prevented by a dangerous phenomenon.

Flurry - A sharp strengthening of the wind, accompanied by a change in its direction and usually lasts within no more than 30 minutes. Shkwals are usually accompanied by front cyclonic activity. As a rule, the squalls arise in the warm season on active atmospheric fronts, as well as when passing powerful cumulating rain clouds. Wind speed in shkwalch reaches 25-30 m / s or more. Shkwal strip width is usually about 0.5-1.0 km, length is 20-30 km. The passage of Shkvalov causes the destruction of buildings, communication lines, damage to trees and other natural disasters.

The most dangerous destruction from the impact of wind occur during the passage mortal - a powerful vertical vortex generated by an upward stream of warm wet air. Tornado has a form of a dark cloud pillar with a diameter of several tens of meters. It descends in the form of a funnel from a low base of a heap-rain cloud, to meet that another funnel can be raised from the earth's surface - from splashes and dust connected from the first. Wind speeds in a tornger reach 50-100 m / s (180-360 km / h), which causes catastrophic consequences. The blow of the rotating wall of the tornger is able to destroy capital buildings. The pressure drop from the outer wall of the tornadow to its inner side leads to the explosions of the buildings, and the upstream air flow is able to raise and transfer heavy items, wreckage of building structures, wheeled and other techniques, people and animals to considerable distances. According to some estimates, in the cities of Russia, such phenomena may be observed approximately every 200 years, but in other areas of the globe are observed regularly. In the XX century The most destructive in Moscow was the Tornado, who was held on June 29, 1909, in addition to the destruction of buildings, nine people were killed, 233 people were hospitalized.

In the United States, where the tornadoes are observed quite often (sometimes several times a year), they are called "Tornado". They differ exceptionally large repeatability compared to European tumors and are mainly associated with sea tropical air. Mexican Gulfmoving towards southern states. Damage and losses caused by these tornadoes are huge. In areas where tornadoes are observed most often, even a kind of architectural form of buildings, called Tornado House. It is characterized by a squat reinforced concrete sheath in the form of a broken drop, having door and window openings, tightly closing with durable rolling shutters in the event of danger.

Considered above dangerous phenomena Mainly observed in the warm period of the year. In the cold season, the most dangerous earlier than earlier ice and strong blizzard - Transferring snow over the surface of the earth by the wind of sufficient strength. Usually it occurs with the increase in gradients in the field atmospheric pressure And when passing fronts.

Weather stations are monitored by the duration of blizzards and the number of days with a blizzard in the individual months and the winter period as a whole. The average annual duration of missiles on the territory of the former USSR for the year in the south Central Asia Less than 10 hours, on the coast of the Kara Sea - more than 1000 hours. For most of the territory of Russia, the duration of the blizzards is more than 200 hours per winter, and the duration of one blizzard is an average of 6-8 hours.

Bilkeli makes great damage to urban economy due to the sinking of streets and roads, sowing snow in the wind shadow of buildings on the territory of residential building. In some areas of the Far East, the building with a leeward side is noticed so much high layers Snow that after the end of the blizzard, it is impossible to get out.

Bilnels complicate the work of air, rail and road transport, utilities. He suffers from blizzards and agriculture: with strong winds and a loose structure of snow cover on the fields there is a redistribution of snow, the plots are broken, conditions are created for the freezing of winter. Blizzard affects people, creating discomfort while outdoors. Strong wind In combination with the snow disrupts the rhythm of the process of the respiratory process, it creates difficulties for moving and performing work. During periods of blizzards, so-called meteorological heat loss of buildings and energy consumption used for production and household needs are enhanced.

Bioclimatic and architectural and construction value of precipitation and phenomena. It is believed that the biological effect of precipitation on the human body is mainly characterized by a beneficial effect. With their falling out of the atmosphere, pollutants and aerosols, dust particles, including those on which pathogenic microbes are transferred are washed out of the atmosphere. Convective-rave precipitates contribute to the formation of negative ions in the atmosphere. So, in the warm period of the year after a thunderstorm in patients, complaints of meteopathic nature decrease, the likelihood of infectious diseases decreases. In the cold period, when the precipitates are mainly falling out in the form of snow, it reflects up to 97% of ultraviolet rays, which is used in some mountain resorts, while spending sunny baths at this time.

At the same time, it is impossible not to note the negative role of precipitation, namely the problem associated with them acid rain. These precipitations contain solutions of sulfur, nitric, hydrochloric and other acids generated from sulfur oxides emitted in the process of economic activity, chlorine, etc. As a result of the fallout of such precipitation, soil and water pollution occurs. For example, the mobility of aluminum, copper, cadmium, lead and other heavy metals increases, which leads to increased their migration ability and transfer over long distances. Acid precipitates are enhanced by corrosion of metals, thereby having a negative effect on roofing materials and exposed to precipitation metal structures of buildings and structures.

In areas with dry or rainy (snow) climate, atmospheric precipitates are the same important factor in formation in architecture as solar radiation, wind and temperature mode. Special attention is paid to atmospheric precipitation when choosing the design of walls, roofs and bases of buildings, selection of construction and roofing materials.

The effects of atmospheric precipitation on the building consists in moistening the roof and external fences leading to the change in their mechanical and thermophysical properties and affecting the service life, as well as in the mechanical burden on building structures created by hard precipitate accumulating on the roof and protruding elements. This impact depends on the outflow mode and the conditions of removal or the occurrence of atmospheric precipitation. Depending on the type of climate, precipitation can fall uniformly throughout the year or mainly into one of its seasons, and this loss may have a character of shower or drizzling rains, which is also important to take into account in the architectural solution of buildings.

The accumulation conditions on different surfaces are important mainly for solid precipitation and depend on the air temperature and wind velocity, redistributing snow cover. The highest snow cover in Russia is observed on the east coast of Kamchatka, where the average of the largest decades reaches 100-120 cm, and once every 10 years - 1.5 m. In the individual areas of the southern part of the Kamchatka, the average height of the snow cover may exceed 2 m. The height of the snow cover is growing with an increase in the height of the place above sea level. Even small hills affect the height of the snow cover, but the influence of large mountainous arrays is especially great.

To clarify the snow loads and determining the mode of operation of buildings and structures, it is necessary to take into account the possible value of the weight of the snow cover formed during the winter, and its maximum possible increase during the day. Changing the weight of snow cover, which can occur in just a day as a result of intense snowfalls, can vary from 19 (Tashkent) to 100 or more (Kamchatka) kg / m 2. In areas with a small and unstable snow cover, one heavy snowfall during the day creates a load close to its value, which is possible every five years. Such snowfall was observed in Kiev,

Batumi and Vladivostok. These data are especially necessary for the design of light coatings and prepare metal frame structures with a large surface of the roof (for example, canopies over large parking lots, transport and transfers).

The fallen snow can be actively redistributed on the territory of urban development or in a natural landscape, as well as within the roof of buildings. On some sites, it takes place, on others - accumulation. The patterns of such redistribution are complex and depend on the direction and speed of the wind and the aerodynamic properties of urban development and individual buildings, natural relief and vegetation cover.

Accounting for the number of snow tolerable snow is needed to protect against snowdowes of the houses, street road network, automotive and railways. Snowdress data is also needed when planning settlements For the most rational accommodation of residential and industrial buildings, when developing measures for cleaning the snow of cities.

The main snowmanship measures are to choose the most favorable orientation of buildings and a street-road network (UDS), which provides the minimum possible accumulation of snow on the streets and in the entrances to the building and the most favorable conditions for the transit of the snow by the wind through the UDS and residential building.

Features of the postposition of snow around buildings are that maximum deposits are formed with leeward and windward sides to buildings. Immediately in front of the implanted facades of buildings and near their corners, "Pinds of blowing" are formed (Fig. 1.53). The patterns of movement of snow cover in the metelle transfer is advisable to take into account when placing input groups. Entrance groups in the building in climatic areas characterized by large volumes of snow-transfer should be placed from the windward side with the corresponding insulation.

For groups of buildings, the process of redistribution of snow is more complex. Shown in Fig. 1.54 Snow redistribution schemes show that in the traditional building of modern cities of the microdistrict, where the perimeter of the quarter is formed by 17-storey buildings, and the three-story building of the kindergarten is placed inside the quarter, in the interior of the quarter, an extensive zone of snowstorm is formed: the snow accumulates at the entrances

• 1 - initiating stream; 2 - upper flowing branch; 3 - compensatory vortex; 4 - zone of suction; 5 - a viscous part of the ring vortex (revelation zone); 6 - the colliding zone of the oncoming streams (the atmosphere side of the braking);
• 7 - the same, on the leeward side

• - Transfer
• - blowing out

Fig. 1.54. Redistribution of snow within groups of buildings of various floors

Accumulation

residential buildings and in the territory of kindergarten. As a result, on the territory it is necessary to carry out snow removal after every snowfall. In another embodiment, the production of the perimeter is much lower than the building posted in the center of the quarter. As can be seen from the drawing, the second version of the snowmall factor is more favorable. The total area of \u200b\u200bthe zones of transfer and blowing the snow is greater than the area of \u200b\u200bthe zone of snow blood, the space inside the quarter does not accumulate snow, and the care of the territory of residential building in winter becomes substantially simpler. This option for districts with active snowstore is preferred.

To protect against snowdow, windproof green plants, formable in the form of multi-row planting of coniferous trees from the dominant in the snowstorms and forest burst. The effect of these windproof bands is observed at a distance of 20 heights of trees in landings, so their use is advisable to protect against snowdow along linear objects (transport highways) or small construction sites. In areas where the maximum over the winter, the volume of snow transfer is more than 600 m 3 / POG.M. (Vorkuta, Anadyr, Yamal Peninsulas, Taimyr, etc.), the protection of forest bruises is ineffective, the protection of urban-planning, planning means is necessary.

Under the influence of wind, the redistribution of solid precipitation on the roof of buildings occurs. The snow accumulating on them creates loads on the design. When designing, these loads should be taken into account and, if possible, avoid the occurrence of snow accumulation sites (snow bags). A part of the precipitation is blown away from the roof to the ground, the part is redistributed on the roof depending on its size, form and presence of add-ons, lanterns, etc. The regulatory value of the snow load on the horizontal coating projection according to the joint venture 20.13330.2011 "Loads and Impact" should be determined by the formula

^ \u003d 0.7 s in C, p ^,

where with B is a coefficient that takes into account demolition of snow from the coatings of buildings under the action of wind or other factors; FROM, - thermal coefficient; P is the transition coefficient from the weight of the snow cover of the Earth to the snow load on the coating; ^ - The weight of the snow cover on 1 m 2 horizontal surface of the Earth, taken according to the table. 1.22.

Table 1.22

The weight of snow cover on 1 m 2 horizontal earth surface

Snow areas *
The weight of snow cover, kg / m 2

* Accepted on the map 1 of the application "F" to the joint venture "Urban planning".

The values \u200b\u200bof the coefficient of the coefficient of snow from the coatings of buildings under the action of wind depend on the shape and size of the roof and may vary from 1.0 (snow demolition is not taken into account) to several tenths of the unit. For example, for coatings of high-rise buildings with a height of above 75 m with slopes up to 20% C, it is allowed to receive in the amount of 0.7. For dome spherical and conical coercions of buildings on a round plan, when specifying a uniformly distributed snow load, the value of the coefficient with B is mounted depending on the diameter ( from!) Dome base: with B \u003d 0.85 at c1 60 m, with B \u003d 1.0 when c1\u003e 100 m, and in intermediate values \u200b\u200bof the dome diameter, this value is calculated by a special formula.

Thermal coefficient FROM, It is used to take into account the decrease in snow loads with a high heat transfer coefficient (\u003e 1 W / (m 2 (c) due to melting caused by heat loss. When determining snow loads for the lavety coatings of buildings with elevated heat dissipation, leading to the melting of snow, when the roofs are bold 3% coefficient value FROM, is 0.8, in other cases - 1.0.

The transition coefficient from the weight of the Earth's snow cover to the snow load on the coating p directly is associated with the form of the roof, since its value is determined depending on the steepness of its rods. For buildings with single-table and duct coatings, the value of the coefficient P is 1.0 when the coating is 60 °. Intermediate values \u200b\u200bare determined by linear interpolation. Thus, when the coating is biased more than 60 °, the snow is not held on it and almost all slides down under the action of gravity. Coatings with such a bias are widely used in the traditional architecture of the northern countries, in mountainous areas and during the construction of buildings and structures that do not provide sufficiently strong roof designs, dome and tents of towers with a large span and roofs on a wooden frame. In all these cases, it is necessary to provide for the possibility of temporary storage and the subsequent removal of the scaling from the roof of snow.

With the interaction of wind and development, the redistribution of not only solid, but also liquid precipitation occurs. It consists in an increase in their number from the windward side of the buildings, in the braking area of \u200b\u200bthe wind flow and from the side of the windward corners of the buildings, where the preciputes contained in the flowing building of additional air volumes come. With this phenomenon, the molaring of the walls is associated, the marching of interpanel joints, the deterioration of the microclimate of the windward premises. For example, a viewed facade of a typical 17-storey 3-section residential building with a rain with an average precipitation intensity of 0.1 mm / min and wind-growth of the wind 5 m / s intercepts about 50 tons of water. Some of it is spent on wetting the facade and protruding elements, the rest flows through the wall, causing adverse effects for the local territory.

To protect the facades of residential buildings from wetting, an increase in the area of \u200b\u200bopen premises is recommended on the viewed facade, the use of moisture protection screens, water facing, reinforced waterproofing of the joints. On the perimeter it is necessary to provide for drainage trays attached to the storm sewage systems. If they are lacking, water flowing along the walls can purl the surface of the lawns, causing surface erosion of the vegetable layer of soil and damaging green plantings.

In architectural design, issues related to the estimate of the intensity of ice-forming in certain parts of the buildings. The magnitude of the ice load on them depends on the climatic conditions and on the technical parameters of each object (sizes, shape, roughness, etc.). Solving issues relating to the prevention of icehead and related violations of the regime of buildings and structures and even the destruction of their individual parts is one of the most important tasks of architectural climatography.

The influence of the ice on various structures is to form icy loads. The magnitude of these loads has a decisive effect on the choice of constructive parameters of buildings and structures. The ice-frozen deposits of ice are harmful and for wood-shrub vegetation, which makes up the basis of the gardening of the urban environment. The branches break down under their weight, and sometimes trees trunks. The yield of fruit gardens is reduced, agriculture productivity decreases. The formation of ice and the ice on the roads creates dangerous conditions for the movement of land transport.

Much danger to buildings and nearby people and items (for example, parked cars, benches, etc.) are icicles (a special case of iceed phenomena). To reduce the formation of icicles and forehead on the cornices, the project should provide for special events. Passive measures include: reinforced thermal insulation of the roof and attic floors, the air gap between the roof coating and its structural base, the possibility of natural ventilation of the underpants with cold outer air. In some cases, it is impossible to do without active engineering activities, such as the electric heating of the eaves of the eaves, the installation of shockers to drop out by small doses as they are educated, etc.

The architecture has a great influence of the joint impact of wind with sand and dust - dust storms which also belong to atmospheric phenomena. The combination of winds with dust requires the protection of the residential environment. The level of non-toxic dust content in the dwelling should not exceed 0.15 mg / m 3, and not more than 0.5 mg / m 3 is taken as the maximum permissible concentration (MPC). The intensity of the transfer of sand and dust, as well as snow depends on the wind speed, local relief features, the presence of unauthorized areas of relief from the windward side, the granulometric composition of the soil, its moisturity and other conditions. The patterns of sand deposits and dust around buildings and on the territory of construction are about the same as snow. Maximum deposits are formed with leeward and windwards of the building or their roofing.

Methods of dealing with this phenomenon are the same as for the snowpoint. In areas with a large dusty of air (Kalmykia, Astrakhan Oblast, Caspian part of Kazakhstan, etc.) Recommended: Special layout of dwellings with the orientation of the main premises for a protected side or with a dust shown glazed corridor; corresponding to the planning of quarters; Optimal direction of streets, forest protection stripes, etc.

Atmospheric precipitates are called water, which falls from the atmosphere to the earth's surface. Atmospheric precipitates have a more scientific name - hydrometeors.

Measure them in millimeters. To do this, the thickness of the water dropped to the surface with special instruments - sediments. If you need to measure the thickness of water on large areas, meteorological radars are used.

On average, our land gets almost 1000 mm of precipitation annually. But it is quite predictable that their amount of moisture dropped depends on many conditions: climate and weather regimens, terrain and vicinity of reservoirs.

Views of atmospheric oyphans

Water from the atmosphere falls onto the earth's surface, being in two respects - liquid and solid. On this principle, all atmospheric precipitations are made to divide on liquid (rain and dew) and solid (hail, frost and snow). Consider each of these species.

Liquid atmospheric precipitation

Liquid atmospheric precipitates fall on the ground in the form of water droplets.

Rain

Steaming from the surface of the earth, water in the atmosphere is assembled into the clouds, which consist of the smallest drops, sizes from 0.05 to 0.1 mm. These miniature droplets in the clouds are merged with each other over time, becoming more and more in size and noticeably harder. Visually this process can be observed when the snow-white cloud begins to darken and heavily. When such droplets in the cloud becomes too much, they spill on the ground in the form of rain.

Summer rain is in the form of large droplets. Large they remain because the heated air rises from the ground. Here are these ascending jets and do not give drops to break into smaller.

But in the spring and autumn, the air is much cooler, so during these seasons the rains are drizzling. Moreover, if the rain comes from layered clouds, it is called covered, and if the drops begin to fall out of cube rain, then the rain turns into a shower.

Every year, almost 1 billion tons of water is spilled in the form of rain on our planet.

In a separate category it is worth highlighting moro. This type of precipitation also falls out of layered clouds, but its drops are so small, and their speed is so insignificant that water droplets seem susceptible in the air.

Dew

Another type of liquid precipitation, which falls at night or early in the morning. Dew droplets are formed from water vapor. Overnight, this pair cools, and water from the gaseous state turns into a liquid.

The most favorable conditions for the formation of dew: clear weather, warm air and almost the absence of wind.

Solid atmospheric precipitation

Solid precipitates We can observe in the cold season when the air is cooled to such an extent that the water droplets in the air freeze.

Snow

Snow as well as rain, is formed in the cloud. Then, when the cloud enters the air flow, in which the temperature is below 0 ° C, the water droplets in it freeze, become heavy and fall on the ground in the form of snow. Each droplet froze in the form of a kind of crystalline. Scientists argue that all snowflakes have different shape And find the same simply impossible.

By the way, the snowflakes fall very slowly, since almost 95% consist of air. For the same reason, they are white. And the snow crushes under the legs because crystalline breaks. And our rumor is able to catch this sound. But for fish, real torment, as snowflakes falling on the water, publish a high-frequency sound that is hears fish.

Grad.

it falls only in the warm season, especially if the day before it was very hot and stuffy. Heated air strong streams rushed up by carrying out the evaporated water. Heavy cumulus clouds are formed. Then, under the influence of ascending flows, the droplets of water in them are heavy, begin to freeze and finish crystals. These are these chickles of crystals and rushed to the ground, by the way increasing in size due to merging with drops of supercooled water in the atmosphere.

It should be borne in mind that such ice "snowballs" rushed to the ground with an incredibly speed, and therefore hail is able to punch slate or glass. Grad causes great damage to agriculture, therefore the most "dangerous" clouds that are willing to break out hail, accelerate with special guns.

Frost

Inay, as well as dew, is formed from water vapor. But in winter and autumn monthsWhen it is already cold enough, the water droplets freeze and therefore fall out in the form of a thin layer of ice crystals. And they do not melt because the land cools even more.

Seasons of rainy

In the tropics and very rarely in moderate latitudes, this time of year comes when it falls out to be exorbitantly a large amount of precipitation. This period is called the rainy season.

In countries that are located in these latitudes, there are no harsh winters. But spring, summer and autumn are incredibly hot. For this hot period accumulates a huge amount of moisture in the atmosphere, which is then poured in the form of protracted rains.

In the equator zone, the rainy season comes twice a year. And in the tropical belt, south and north of the equator, this season happens only once a year. This is due to the fact that the rainy belt gradually runs from the south to the north and back.