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Jet streams, their classification, conditions of formation and flights in them. General circulation of the atmosphere. Jet streams. Trade winds. Monsoons

The influence of wind on aircraft motion parameters is most significant at high wind speeds, especially in the region of jet streams (ST).
ST is the transport of air in the form of a narrow current with high speeds, usually in the upper troposphere and lower stratosphere with an axis near the tropopause. The maximum wind speed (30 m/s and >) is observed on the ST axis. The change in wind speed in the ST area is usually 5-10 m/s per 1 km altitude and 10 m/s and > 100 km in the horizontal direction.

STs are formed in zones of closest convergence of warm and cold air masses, where significant horizontal gradients of pressure and temperature are created. Since the greatest temperature contrasts in the zones of atmospheric fronts are observed in the cold. half of the year, then during this period STs are most active.

The navigational significance of jet streams is difficult to overestimate. On the one hand, cirrus and cirrocumulus clouds and intense turbulence often occur in the ST zone, and on the other hand, strong wind in the ST zone significantly changes the speed of the aircraft.

Intense turbulence is observed mainly on the cold (cyclonic) side of the ST, where temperature and wind gradients are greater. On the ST axis, strong turbulence occurs much less frequently.

If the flight in the ST zone occurs against the wind, then the ground speed sharply decreases, if with the wind, it increases. When flying over long distances, you can use CT to reduce flight time and increase flight range. Currently, there are methods that, based on wind field data, suggest the most advantageous route along which the aircraft will fly to its destination either with the least amount of time or with the least fuel consumption. All of the above indicates the great navigational significance of the ST.

22. Classification of air masses (a)geographical ( arctic, temperate and tropical air, each of the air is continental or maritime depending on the conditions of formation); b) according to the conditions for the development of convection (stable and unstable).



a) Depending on the position of the source of air formation in one of the main thermal zones of the globe and taking into account the nature of the underlying surface (ocean or continent), they are distinguished following types air masses:

Arctic or Antarctic air (AB) - marine (mAV) and continental (kAV) - is found in the northern and southern polar regions of ice and snow;

Air of temperate latitudes (LA) - sea air (mLA) and continental air (CLA) - is located in temperate latitudes;

Tropical air (TV) - sea (mTV) and continental (kTV) - is located in the trade wind areas of the northern and southern hemispheres;

Equatorial air (EA) - located at the equator between the northern and southern trade winds.

The sea air is different high humidity. It is around 80% everywhere. In addition, there are differences in temperature conditions. IN summer time in temperate latitudes it will be colder than continental, and in winter - warmer.

Arctic and Antarctic air, due to the predominance of ice fields and land in high latitudes, is rarely maritime Arctic air (MAA). They do not divide the air into sea and continental equatorial air, since over land and over the sea it is equally warm and humid due to the huge amount of precipitation.

b) An air mass in which there are no conditions for the development of upward air movements (convection) is called stable. Vertical movements can only occur in the form of dynamic turbulence with horizontal air movement. This air mass usually includes warm masses.

An air mass in which there are conditions for the development of upward air movements (convection) is called unstable. Unstable masses usually include cold masses.

23. Wind - direction and speed, classification: weak, moderate, strong, storm, variable, gusty, squall.

Wind– this is the horizontal (advective) movement of air relative to the earth’s surface, characterized by direction and speed.

Direction given by the angle (or rhumb δ=22.5 0), counted from the north direction clockwise

Velocity value is set by the feathering on the arrow (small feather – 2.5 m/s, large feather – 5 m/s, blackened triangle – 25 m/s)

Based on the wind speed, the following are distinguished:

1) < 3 м/с – слабый

2) 4-7 m/s – moderate

3) 8-14 m/s – strong

4) 15-19 m/s – very strong

5) 20-24 m/s – storm

6) 25-30 m/s – severe storm, hurricane.

7) Changing wind– in 2 minutes the direction changes by more than 1 point.

8) Gusty– in 2 minutes the wind changes by 4 m/s or more.

9) Squall– short-term sharp increase in wind up to 20 m/s or more with a significant change in direction.

24. Local winds: foehn, bora, breeze, intramass squall, blood clots, tornadoes, tornadoes. Conditions for aviation.

Local winds - winds characteristic of certain areas associated with the peculiarities of local orography, the proximity of land and water, etc.

1.Breeze - this is the wind coastline seas and small lakes with sharp daily changes in directions (layer 1-2 km).

Night breeze: Day breeze:

2. Hairdryer (garmsil) - a warm, dry gusty wind blowing from the mountains to the valley.

Peculiarities:

1. Significantly increases the temperature (by 30 0 in a few hours) and lowers the humidity (to 4-5%).

2. Duration – from several hours to several days.

3. Causes severe vibration of the aircraft.

3.Bora – strong (V> 20 m/s) cold gusty wind blowing from low mountain ranges towards the warm sea.

4. Squalls - sharp short-term wind increases (up to 20 m/s). They can be intramass (in convective Cb) and frontal (in several places along the HF of the 2nd kind – squall line).

P.S. Ci - cirrus, Cs - cirrostratus, Cb - cumulonimbus, Cu - cumulus,

Ns – nimbostratus, St – stratus.

Squall Gate (HF)- a vortex with a horizontal axis that occurs in the front part of a thundercloud.

5. Thrombus (tornado, tornado) – special small-scale eddies (d=1-100 m, h=1 km, movement speed – 20-30 km/h, lifetime – 1-10 min, pressure in the center is reduced by 10-100 hPa).

Peculiarities:

1. Originates at the front of a thundercloud and penetrates from above all the way to the Earth;

2. Observed in temperate and tropical latitudes in warm and humid, unstable stratified VM;

3. Air rotation around an axis as in a cyclone with v=70-100 m/s;

4. Presumably a type of thunderstorm squall;

5. The energy of a typical tornado with a radius of 1 km and an average speed of 70 m/s is equal to the energy of a standard atomic bomb of 20 kilotons of TNT.

6. Mountain-valley winds (up to 10 m/s) – expressed in the warm season, filling the entire cross-section of the valley, vertical thickness – the average height of the ridges.

25. Cyclonic activity. Stages of cyclone development. Formation of anticyclones. Flight conditions in different parts cyclones and anticyclones, in the zone of atmospheric fronts.

Cyclone – an area of ​​low pressure, limited by closed isobars with minimum pressure in the center.

Anticyclone – an area of ​​high pressure, limited by closed isobars with maximum pressure in the center.

According to the baric law of wind:

1) In a cyclone circulation occurs counterclockwise, in an anticyclone it circulates clockwise.

2) The wind speed in a cyclone is on average higher in magnitude than in an anticyclone.

NEEDS TO BE DONE

26. Weather minimums.

Weather minimum – a term denoting the maximum weather conditions under which a trained aircraft commander is permitted to fly, operate an aircraft, and use the airfield for takeoff and landing.

Weather minimum defined:

Height of the cloud base (decision height)

Visibility (visibility on the runway)

P.S. Runway visibility – the maximum distance within which the pilot of an aircraft located on the center line of the runway can see the markings of the runway surface or the lights that limit the runway or indicate its center line.

Decision height – the established relative altitude at which the missed approach maneuver must be started if, before reaching this altitude, the aircraft commander had not established visual contact with landmarks to continue the approach, and also if the position of the aircraft in space or the parameters of its movement are not ensure a safe landing.

Weather minimums include:

Aerodrome

Aircraft

Commander of the Armed Forces

Types of aviation work

Aerodrome Minimums depends on geographical location airfield and its equipment with landing systems.

Consists of the minimums:

  1. for takeoff– these are the minimum permissible values ​​of visibility on the runway and the height of the base of the clouds at which it is permitted to take off on an aircraft of this type.
  2. for landing– minimum permissible values ​​of visibility on the runway and decision altitude at which it is permitted to land on an aircraft of this type.
  3. takeoff training (1)
  4. training for landing(same characteristics as for item (2) for training flights only.

Minimum aircraft are determined by the availability and quality of special navigation equipment available on board the aircraft.

Consists of the minimums:

  1. for takeoff– minimum permissible runway visibility values ​​that allow safe takeoff on an aircraft of this type.
  2. for landing– minimum permissible values ​​of runway visibility and decision heights that allow for safe landing on an aircraft of this type.

Minimum aircraft commander conditioned and determined by the personal training of the pilot.

Consists of the minimums:

  1. for takeoff– the minimum permissible value of visibility on the runway at which the commander is allowed to take off on an aircraft of this type.
  2. for landing– minimum permissible values ​​of visibility on the runway and decision altitude (Height of the cloud base), at which the commander is allowed to land on an aircraft of this type.
  3. for flight under visual flight rules and special visual flight rules– minimum permissible values ​​of visibility and height of the cloud base at which the commander is allowed to perform visual flights on an aircraft of this type.

Minimum type of aviation work – the minimum permissible values ​​of visibility and height of the base of clouds at which it is permitted to perform aerial work using flight rules (visual or instrument) established for this type of work.

  1. first category (60m), runway visibility (800m).
  2. second category– height of the cloud base (less than 60m, but not less than 30m), runway visibility (less than 800m, but not less than 400m).
  3. third category– height of the cloud base (less than 30m), and visibility on the runway (less than 400m).

Divided by:

III-A– visibility on the runway (at least 200m).

III-B– visibility on the runway (at least 50m).

III-C– visibility on the runway (equal to 0 meters).

P.S. During takeoff and landing, 3 weather minimums are taken into account: the airfield, the aircraft and the aircraft commander, from these three you select greatest.

If the airfield minimum is 100x1000, the aircraft minimum is 50x500, the aircraft commander minimum is 80x1500, then this pilot on this plane can board this airfield in weather no worse than 100x1500.

27. The influence of temperature and air density on engine thrust, required speed, and aircraft ceiling.

The dependence of the available thrust on meteorological conditions determines their influence on other important aircraft performance characteristics - maximum speed flight, rate of climb, aircraft ceiling, as well as fuel consumption.

One of the most important flight performance characteristics of an aircraft is its ceiling- the highest altitude to which an aircraft can rise under a certain flight regime.

There are:

Theoretical The ceiling is the height at which excess thrust and vertical velocity are zero.

Practical The ceiling is the height at which the maximum vertical speed for jet aircraft is 5 m/s, and for piston aircraft - 0.5 m/s.

Static The ceiling is the highest altitude of horizontal flight at a constant speed.

Dynamic ceiling is the highest height achieved through the use of kinetic energy aircraft, i.e. due to loss of speed.

At these altitudes, fuel consumption decreases and flight range increases. If the ceiling of the aircraft allows you to fly above the tropopause, then this, in addition to the above-mentioned advantages of flying near the ceiling, helps to overcome zones of thunderstorm activity, intense turbulence, icing and other adverse meteorological conditions observed in the troposphere. However, it should be borne in mind that near the ceiling the aerodynamic qualities of the aircraft deteriorate, since large angles of attack are used here, causing loss of stability and controllability. The ceiling of an aircraft depends on the physical state of the atmosphere. For most modern aircraft it exceeds the tropopause altitude.

28. Dangerous weather phenomena for aviation (indicate where the specified phenomenon is formed and what is the danger for flights): Atmospheric turbulence (thermal, orographic, dynamic) and aircraft roughness. Clear sky turbulence (where is it observed?). Wind shears and their impact on aircraft takeoff and landing. At what wind shear values ​​are take-off and landing prohibited? Aircraft icing, control methods. At what rate of ice growth on aircraft bearing surfaces is icing considered severe? Thunderstorm activity. Classification of thunderstorms, squall. Static electricity.

Turbulence

· Occurs during thunderstorms, on AF, with vertical wind shear ∆v/∆h (with radiative, advective and orographic inversions), in ST zones with clear sky(TYAN on the cyclonic periphery), in mountainous areas (orographic bumpiness), in cumulus clouds, in unstable VMs.

· Causes overloads (ratio of lift to gravity), impairs aircraft controllability

According to the conditions of education, there are:

1) Thermal turbulence (unsteady VM)

2) Dynamic turbulence:

On surface AF with horizontal gradients T more than 2 C per 100 km, horizontal gradients of wind speed - more than 20 km/h per 100 km,

Cloudiness

Near the main (climatological) fronts (PVFZ, ST), more often these are TN, synoptic situations with significant convergence or divergence of isohypses

3) Mechanical (orographic) turbulence:

· (as a result of air friction on the underlying surface), on the windward side there is often wind shear, on the leeward side there is a “rotor”),

· With stable stratification and v>10 m/s, increasing with height – mountain waves with a wavelength of 5-50 km, h=(3-4) Hhr, with high humidity- lenticular clouds.

Dimensions and frequency of turbulence zones

85-90% of cases: Δz <1000 м,

(At temperate latitudes Δz <500 м, Δl~40 km 80%

The probability of getting into bumps when changing flight levels is higher than during level flight.

In the troposphere: greatest repeatability of turbulence in a layer of 0-2 km (thermal and mechanical turbulence) and in a layer of 8-12 km (dynamic).

Bumpiness intensity

Weak - Δn < + 0.5 g at flight level

And Δn < + 0.3 g on descent glide path

Moderate - Δn < (0,5-1) g на эшелоне

And Δn < ( 0.3-0.4) g on the descent glide path

Strong - Δn> 1 g at flight level

And Δn> 0.4 g on descent glide path

Electrification

Damage to BC by electric discharges occurs in Cb, Ns, Sc, St – at E>10 6 V/m

Frequent in the zone of HF of the 1st kind, in Cb, which have not reached the stage of a thundercloud;

Weak electrification in Ci, St (TF, HF).

The occurrence of radio interference

Yaw of radio compass needles,

Failures of onboard radars, antennas,

Damage to the casing

Jet streams is a strong air flow with a horizontal axis in the upper troposphere or lower stratosphere, characterized by large vertical and lateral wind shears. The jet stream typically extends thousands of kilometers long, hundreds wide, and several kilometers thick. The vertical shift is on the order of 5-10 m/s per 1 km, lateral - on the order of 5-10 m/s per 100 km. The lower speed limit along the axis of the jet flow is chosen arbitrarily and is equal to 30 m/s. The core of the jet stream, where the wind speed differs little from the speed on the axis, is only 50-100 km wide and 1-2 km thick.

In the works of many scientists, conclusions about the features of the distribution of the jet stream are made based on the analysis of maps of the frequency of strong winds(100 km/h) on an isobaric surface of 300 mb (9-10 km). According to these researchers, such maps reflect not only repeatability strong winds on the surface 300 mb (at an altitude of 9-10 km), but to a greater extent the repeatability of the jet stream, since wind speeds of 100 km/h are, as a rule, characteristic only of the jet stream. At the same time, it was forgotten that the main feature of the jet stream is the specific nature of the wind field, determined by the presence at a certain height of a maximum wind speed, in all directions from which in the plane of the vertical section the wind speed decreases. In this regard, in a vertical section, the jet stream is represented in the form of closed concentric isotopes ().

Obviously, the very physical nature of the phenomenon eliminates the need to introduce restrictions on the value of the maximum wind speed on the axis of the jet stream, just as it would be physically unjustified, for example, to use any criteria for values ​​​​at the centers of cyclones or anticyclones.

The simplest picture of the distribution of jet streams in the troposphere is presented in. In tropical latitudes up to an altitude of approximately 18 km, weak and inconsistent easterly trade winds are observed.

Between the belts of low-latitude and high-latitude easterly winds there is a system of stable westerly winds, which is called the westerly transport. Western winds blow in the layer from the surface of the earth to a level of 20 km. In some areas, the speed of these winds increases sharply, then two or three rapidly moving streams are formed within the wind system. These flows are jet streams. Planes that fly from west to east have an advantage over those that fly from east to west because they can take advantage of these jet streams.

Jet streams are associated with high-altitude frontal zones(WFZ). The greater the temperature gradient in the free atmosphere, the greater the air flow velocity on the jet axis. In the troposphere, jet streams are especially often found in subtropical latitudes, the axis of which is located in the latitudinal zone of 35-45° in summer, and in the latitudinal zone of 25-35° in winter. These are the most stable and intense jet streams, most often observed over the western part of Atlantic Ocean, areas of the Red Sea and India, over the Pacific Ocean southeast of Japan.

In addition, a distinction is made between arctic and polar-front jet currents observed in middle and high latitudes, equatorial, and stratospheric ones. Arctic and polar-front jet currents (at altitudes of 6-8 km) are associated with the main atmospheric fronts - polar and Arctic. The greatest frequency and intensity of these jet streams is observed over the eastern shores of Asia and North America. Over the territory of Russia they are most often observed over the Far East, south Western Siberia, the Urals, and in winter - over Central Asia.

Near the axis of the jet stream, large vertical gradients of wind speed are observed, reaching 20-25 m/s per 1 km altitude and 16 m/s per 100 km horizontally. In this regard, strong turbulence, which is observed in the upper troposphere under clear skies, is in most cases associated with jet streams. Cloud formation is associated with jet streams.

Statistics based on reports from aircraft crews show that turbulence in jet streams, causing aircraft to flutter, occurs most often on the cold (cyclonic) side of the jet and somewhat less frequently on the warm (anticyclonic) side of the jet. This is explained by the fact that on the cyclonic side of the jet the vertical and horizontal gradients of wind speed are approximately 1.5 times greater than on the anticyclonic side.

When I hear “horror stories” about global warming, I remind the next prophet of the imminent destruction of humanity that during one summer thunderstorm the energy of 13 atomic bombs like the one dropped on Hiroshima is released. And let’s not even talk about the energy of hurricane winds. So the pitiful efforts of civilization are incomparable with the mighty forces of nature. Oh, rightly said one of the heroes of the immortal novel by J. Hasek: “What is Captain Wenzel compared to the splendor of nature?” Humanity is still a long way from polluting its planet to the point of making it impossible to live on it!

The source of energy for the grandiose processes occurring in the atmosphere is, of course, the Sun. And the reason for the occurrence of these processes is that solar energy falls on the Earth’s surface unevenly. Closer to the equator, the land surface and ocean surface warm up much more than at the poles. As a result of this unevenness, air currents arise in the atmosphere, transferring heat from warmer to cooler regions of the Earth. This is a consequence of a fundamental law called the second law of thermodynamics.

The air heats up in hotter places, becomes lighter and rises upward to a height of 9-12 kilometers. Warm air cannot rise higher due to the counteraction of gravity. But it is not able to cool down quickly either - the heat reserve is too large. Therefore, air currents are diverted to the poles, where it is cooler.

However, they do not have time to reach the poles; somewhere around 30 degrees north or south latitude, the air finally cools, sinks to the surface of the Earth and now flows down to warmer areas, that is, again to the equator. This is how constant winds, trade winds, are formed. They blow in a southwesterly direction in the northern hemisphere and in a northwesterly direction in the southern hemisphere. The shift of winds to the west is a consequence of the rotation of the Earth.

From the poles cold air moves along the surface of the earth to where it is warmer, that is, to the southern latitudes. At the same time, it gradually warms up and somewhere around the 60th latitude it begins to rise upward, to the boundary of the troposphere, to a height of about 9 kilometers. At this altitude, warm air returns to the polar regions, gradually giving up its heat. Near the pole, it, cooled, descends to the surface of the earth to move again to warmer areas.

Between these two circular air flows, another, intermediate one arises. In it, cold air, which has not had time to heat up in the region of 30 degrees latitude, moves, gradually heating up, along the surface of the Earth and, having warmed up enough, rises. Along the boundary of the troposphere it returns to the south, where, having cooled, it again descends to the earth's surface.

In places where these circular air currents touch, cold and warm air fronts interact. As a result of this interaction, rain falls at the surface of the Earth, thunderstorms occur, as well as hurricanes, storms and tornadoes.

What happens at high altitudes, where cold and warm air fronts also collide? The humidity here is very low, so neither rain, nor snow, nor hail will fall here. But grandiose hurricane “craters” arise here with ease. But they are not directed vertically, as at the surface of the Earth, but horizontally. So they act like giant fans, creating thin bands of swirling air called jet streams.

Jet streams are narrow regions about 2 kilometers high. Their width ranges from 40 to 160 kilometers. These are sort of air “pipes” through which air rushes at a speed of 400 - 500 kilometers per hour. The length of the jet stream can vary greatly depending on the air speed. It happens that one jet stream encircles Earth in the region of 30's and 60's latitudes. It happens that one long jet stream breaks into several shorter jet streams.

Meteorologists first recorded jet streams in the earth's atmosphere in 1883. This year it happened catastrophic eruption Krakatoa volcano in Indonesia. Clouds of smoke and volcanic ash rose to stratospheric heights - more than 12 kilometers. Some of the ash and dust was captured by jet streams, making these streams clearly visible from the Earth's surface.

In 1920, Japanese meteorologist Wasaburo Oishi launched meteorological Balloons from the top of Mount Fuji and discovered that upon reaching heights of about 9 - 10 kilometers they were sharply carried away in an easterly direction. Oishi is lucky because one of the jet streams passes just over Japan. But his work was practically unknown in other countries. Therefore, the jet streams were rediscovered by American pilots in 1945. The “Flying Fortresses” B-17 and B-29 flew at altitudes of over 10 kilometers at speeds of about 500 kilometers per hour. At such altitudes they were inaccessible to the fighters of that time, and the Americans used these aircraft to bomb targets on the Japanese islands. It turned out that the flight to the bombing site took much longer than the return flight. Moreover, some bombers, falling into a jet stream in which wind speeds reached 400 - 500 kilometers per hour, simply “hung”, unable to move forward!

Modern passenger aircraft fly at altitudes above 10 kilometers. Sometimes they use jet streams to speed up their flight from west to east. However, the planes fly nearby, trying not to get caught in the current itself. After all, here the flow swirls, as a result of which the plane begins to “chatter” a lot.

Weather anomalies in Russia have become a subject for research by foreign scientists. A number of meteorologists and climatologists have noted that too many countries have experienced extreme weather this year.

In addition to the heat in Russia, there is the worst flooding in Pakistan in 80 years, unusually intense heat in July in Japan (which killed more than 60 people), and hot June weather in the United States and Canada.

According to meteorologists who regularly monitor the atmosphere in the Northern Hemisphere, these phenomena at the global level represent “links of the same chain.”

They are caused by the unusual behavior of high-altitude jet streams in the atmosphere.

Such a current (in English it is called jet stream) is a powerful air flow at an altitude of 7 to 12 kilometers above the Earth's surface.

High-altitude jet currents move from north to south and from west to east, and they have a rather sinuous shape due to the influence of a number of factors. The main of these factors are the so-called Rossby waves - low-frequency, predominantly horizontal wave-like movements caused by the rotation and sphericity of the Earth. These waves are rather vortices that circulate between the hemispheres of the planet and, in particular, play a role in the formation of the El Niño phenomenon - fluctuations in the temperature of the surface layer of water in the equatorial part Pacific Ocean, which have a significant impact on climate.

In the past few weeks, meteorologists have noticed changes in high-altitude jet streams in the atmosphere, as reported this week by popular science magazine New Scientist. Meteorologist from the University of Reading (UK) Mike Blackburn, who was involved in such observations, told Gazeta.Ru what the hypothesis is that he and his colleagues adhere to, explaining why there was such heat in Russia and what connection this anomaly has with other extreme natural phenomena.

— In the Northern Hemisphere of the Earth, throughout July, systematic bends in the high-altitude jet stream were observed, extending from the Atlantic over Europe and Asia.

This summer is hot wet air from Africa got rid of moisture over Eastern Europe and in the form of hot dry air brought heat far to the north. There, the bend of the jet stream “blocked” the anticyclone and on for a long time caused a record high temperature, which provoked forest fires and smog, which could cause serious negative consequences for human health. A little further to the east, cold air moved south, entering the monsoon region over the mountainous regions of northern Pakistan and intensifying the seasonal rains there between July 28 and July 30. Most likely, intense rainfall over parts of China in early August and heatwaves in Japan in July are also a consequence of bending high-altitude jet streams. Also, probably, a stable anticyclone over Russia led to the fact that moist air from Mediterranean Sea caused intense rainfall in eastern Germany on 6 August.

— Why have there been systematic bends in the high-altitude jet stream this year?
“We don’t know the answer to this question.” Such changes are part of the natural variability of the atmosphere, which leads to changes in weather over the course of a week, a month or an entire season. But jet streams can explain, in particular, the floods in Great Britain in June-July 2007, and the fairly wet summer throughout Western Europe in 2008 and 2009.

— Could changes in the high-altitude jet stream be a consequence of climate change on Earth?
— Individual abnormal weather phenomena, such as heat waves in Russia or floods in Pakistan, cannot be attributed to global warming, but a higher average temperature poses the risk of an increase in anomalous phenomena, since warm air has a large number of water vapor and an increase in temperature may lead to an increase in average precipitation. To assess the likelihood of flooding during extreme rainfall events, many factors must be considered. Thus, in Pakistan, hydrologists drew attention to cases of incorrect use water resources, which influenced the severity of the flooding. It is worth noting that the scale of emergency relief and recovery in Pakistan, as in many developing countries, grows with the increase in population.

— Is it possible that the weather anomaly will repeat in Russia in next year?
— We, at the University of Reading, do not make such a forecast; other organizations make seasonal forecasts based on computer models. Many researchers make long-term forecasts for specific regions using statistical weather correlations and external factors. But high-altitude jet streams are an integral part of global atmospheric circulation, and changes in the current affect the weather at any time of the year in any place, including next year in Russia.

— Will you and your colleagues investigate the current weather anomaly in Russia?
— Until now, we have only made a preliminary assessment of what was observed in Lately phenomena, but we are conducting a project to study the influence of jet streams on the weather, and our research group should soon defend a dissertation on this topic. True, it will be associated with the floods in the UK in 2007, and not the current heat in Russia.

- Can it be said that modern science is not yet able to take into account many factors that influence the weather, such as solar activity and the number of Arctic glaciers?
- Yes. And I believe that climate and weather models can and should include a range of various factors, such as solar activity or increasing concentrations of greenhouse gases. This is already being done in a number of organizations, for example, in the European Center for Medium-Range Weather Forecasts.

Meanwhile NASA satellites continue exploration of the territory covered by fires in Russia from space. In addition to data on the number of forest fires in different regions countries satellites transmitted to Earth information about the distribution carbon monoxide from fires - over the territory of Russia and beyond its borders.


Air masses at the equator heat up and hot air rises up - there is low pressure. The rising air flows north or south, cools and sinks. Air masses move away from the area high pressure to the low pressure area. Air from the south and north is again directed towards the equator. A vertical circulation system is formed in the atmosphere, encircling the Earth - these are the so-called Hadley cells, Ferrel cells and Polar cells. At the junctions of cells of low and moderate latitudes, the flows are directed downward - the zone of westerly surface winds. In the region of contact between cells of high and middle latitudes, the air, on the contrary, rises - a zone of eastern surface winds and the jet stream at high altitudes. The Coriolis force affects the direction of movement of circulating air masses - they do not move strictly along parallels, but are deviated. This is how specific wind systems arise in each zone. In the polar regions, air masses move from east to west, deviating from the poles. In zones of westerly wind, under the influence of the Coriolis effect and other forces, air masses move eastward. In the trade wind zones of the Northern Hemisphere, the wind blows from the northeast, in the trade wind zones of the Southern Hemisphere - from the southeast. IN upper layers atmosphere, powerful jet currents are formed from west to east, arising due to differences in pressure and temperature

What do we know about the Earth's blue atmosphere? Let's take a short journey into its depths.

When talking about the atmosphere as a whole, it is divided into four large areas, into four “floors”. The first one is the most Bottom part atmosphere - troposphere. The upper limit of this area is different places different. At the equator it extends to a height of 15-18 km, and at the poles - only to 7-9. Four-fifths of the air mass is found here, and it is here that weather is formed.

The second floor of the atmosphere is called the stratosphere. Interestingly, it does not lie immediately behind the troposphere, but is separated from it by an intermediate layer of air (1-3 km thick) - the tropopause, or substratosphere. It's like a small transition between floors. The position of this transition does not remain constant. It either goes down or goes up.

Special jet streams in the atmosphere are associated with the tropopause. This mysterious phenomenon was encountered, for example, during the American intervention in Korea. The soldiers of the People's Army observed a very strange picture from the ground. Some American bombers flying on high altitude, suddenly stopped in the air, and sometimes even began to slowly back away! Frightened by the unusual phenomenon, the American pilots thought that People's Army North Korea is using something new against them, secret weapon. It turned out that the planes fell into “rivers of air” - peculiar air currents flowing at very high speeds.

The study of these unusual flows showed that they are formed, as a rule, at the tropopause. Air currents indeed, in many ways they resemble large rivers. Their width is 100 kilometers or more, and their depth is several kilometers. The flow speed of the “rivers of air” is unusually high. It sometimes reaches -350-400 km per hour. To imagine this speed, it is enough to remember that during the strongest tropical hurricanes, the wind speed rarely exceeds 200-250 km per hour. Such a wind uproots mighty trees, destroys very strong buildings, and drives river water back. And the flow of “air rivers” is even faster!

It is not surprising that planes falling into this “river” cannot fly against the current. A terrible wind extinguishes almost all their speed. “Air rivers” arise in different areas and quickly mix. They are quite winding and stretch for hundreds and thousands of kilometers. Stratospheric jet currents are also known, occurring at an altitude of 25-30 km.

It has been noticed that in our temperate latitudes there are much more “rivers of air” than above the tropics and at the poles. When an airplane flies along the flow of such an “air river,” it sharply increases speed. There is a known case when a scheduled plane flying from the USA to England unexpectedly arrived at its destination 3 hours ahead of schedule. It turned out that he found himself in an “air river” and its rapid “waves” added several hundred kilometers of additional speed to him.

The stratospheric level rises to 80-90 km above the earth's surface. The weather here is consistently clear, but strong winds often blow. Research recent years showed that the stratosphere has its own winter and its own high-altitude summer. Polar regions, temperate latitudes and the equator zone are found here.