Rumba of the horizon

1. Wind speed and direction.

2. Forces acting on the wind. Theoretical types of wind.

3. Wind regime in RB.

1. Wind speed and direction

Wind - horizontal air movement relative to the earth's surface.

In the atmosphere, movements of various scales are observed - from tens to hundreds of meters (local winds) to hundreds and thousands of kilometers (cyclones, anticyclones, trade winds, monsoons). Air currents are directed from high pressure areas to low pressure areas. The outflow of air goes on until the pressure difference disappears.

1.1. Wind speed

The wind is characterized by a speed vector. Wind speed can be measured in various units: meters per second (m / s), kilometers per hour (km / h), knots (nautical miles per hour), points. Distinguish between smoothed wind speed (for a certain period of time) and instantaneous.

Near the ground, the average wind speed is usually 5–10 m / s and rarely exceeds 12–15 m / s. In tropical hurricanes, it reaches up to 60–65 m / s, in gusts - up to 100 m / s; in tornadoes and blood clots - 100 m / s and more. Maximum measured speed 87 m / s (Adelie Land, Antarctica).

Wind speed at most weather stations is measured by rotating cup anemometers, invented in 1846. In addition to cup or vane anemometers, wind speed can be estimated using the Wild board. One of the first anemometers was invented in 1450 by the Italian Leon Alberti. It was a lever anemometer: the wind repelled a ball or plate in the device, displacing them along a curved scale with divisions. The stronger the wind, the more the ball moved. Instruments for measuring wind speed are installed at a height of 10–12 m.

1.2. Direction of the wind

Direction of the wind in meteorology, the direction from which it blows. It can be indicated by naming the horizon point from which the wind is blowing (i.e., bearing) or the angle that forms the horizontal vector of wind speed with the meridian (i.e. azimuth).

The direction of the wind in the high layers of the atmosphere is indicated in degrees, and in the surface - in points of the horizon (Figure 54). During observations, the wind direction is determined by 16 points, but during processing, the observation results are usually reduced to 8 points.

Figure 54 - Rumba of the horizon

The main points (8): north, northeast, east, southeast, south, southwest, west, northwest. Intermediate points (8): north-north-east, east-north-east, east-southeast, south-southeast, south-south-west, west-south-west, north-north-west.

International names of points: north - N - north; east - E - east; south - S - south; west - W - west.

In some places the winds have their own names on the side from which they blow. Example: the Russian wind is the wind from the central regions of European Russia, in the north of European Russia it is the south wind, in Siberia - the west, in Romania - the northeast. In the Caspian region, the north wind is called Ivan, and the south wind is called Mohammed.

Wind direction is determined using weather vane 1 (from gull. vleugel- wing) - one of the oldest meteorological devices. The weather vane consists of a weather vane and a cross of points. Weather vane is often installed at weather stations Wild 2. It consists of a metal flag rotating around a vertical axis above the cross of points, and a Wild board. In anemographs, a Saleiron wheel is used - 2 mills fixed on a movable axis, and an arrow indicating the direction of the wind.

As well as for speed, instant and smooth wind direction are distinguished. Instantaneous wind directions fluctuate significantly around a certain average (smoothed) direction, which is determined by observations with a weather vane. However, the smoothed wind direction in each place of the Earth is constantly changing, in different places at the same time it is also different. In some places winds of different directions have an almost equal frequency of occurrence over a long period of time, in others - a well-pronounced predominance of some wind directions over others throughout the season or year. This depends on the conditions of the general circulation of the atmosphere and partly on the local topographic conditions.

In the climatological processing of wind observations, it is possible for each given point to construct a diagram representing the distribution of the frequency of wind directions over the main points, in the form of the so-called wind rose (Figure 55).

Figure 55 - Repeatability of wind direction in Brest,% (wind rose)

From the origin of the polar coordinates, the directions along the points of the horizon (8 or 16) are plotted in segments, the lengths of which are proportional to the frequency of the winds in this direction. The ends of the line segments can be connected with a broken line. Calm repetition is indicated by a number in the center of the diagram (at the origin). If from the center of the diagram we postpone segments proportional to the average wind speed, then we get a rose of average wind speeds. When constructing a wind rose, 2 parameters can be taken into account simultaneously (by multiplying the frequency of wind directions and the average wind speed in each direction). Such a diagram will reflect the amount of air carried by winds from different directions.

For presentation on climate maps, wind direction is summarized in different ways:

you can map wind roses in different places;

it is possible to determine the resultant of all wind speeds (considered as vectors) at a given place for a particular calendar month over a long-term period and then take the direction of this resultant as the average wind direction;

apply the prevailing wind direction. To do this, the square with the greatest repeatability is determined, the middle line of the square is the prevailing direction.

- (English rhumb). 1) one of 32 compass directions, further subdivided into halves and quarters. 2) part of the horizon \u003d 11.25 degrees. or 1/32 of a circle. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. RUMB 1) 1/32 ... ... Dictionary of foreign words of the Russian language

AND; m. [eng. rhumb] Mor. 1. Division on the compass circle, corresponding to 1/32 of the horizon, to determine the position of the ship in relation to the cardinal points. 2. Direction to the points of the horizon relative to the cardinal points; the angle between two such ... ... encyclopedic Dictionary

- (Point of compass) the constant and well-defined position of the true meridian in a given place of the earth, which determines the direction of the true N S and its perpendicular direction O W, allows the navigator to accurately orientate relative to these ... ... Marine dictionary

The angle between the north or south direction of the magnetic meridian (compass needle) and this direction. The true bearing is counted from the sowing. or south. the direction of the true (astronomical) meridian. The points are counted to the right and left of the meridian ... Geographical encyclopedia

point - compass bearing An alphabetic designation of the direction indicated on the compass cards, permitted but not required. On a full circle, there are 32 rumba, which are equally spaced from one another on the card, as a result of which an arc between two ... Technical translator's guide

Rumba, rumba, husband. (from the Greek rhymbos circle, circular motion) (mor.). Each of the 32 divisions on the compass circle corresponding to each 1/32 of the horizon. To keep a course along such a rumba. Ushakov's explanatory dictionary. D.N. Ushakov. 1935 1940 ... Ushakov's Explanatory Dictionary

RUMB, ah, husband. (specialist.). 1. The direction to the points of the visible horizon relative to the cardinal points or the angle between two such directions. 2. Division on the compass circle, corresponding to 1/32 of the horizon circle. | adj. rumbovy, oh, oh. Sensible ... Ozhegov's Explanatory Dictionary

Angle, stroke Dictionary of Russian synonyms. bearing noun, number of synonyms: 2 angle (27) stroke (21) ... Synonym dictionary

- (English rhumb) direction to points of the visible horizon relative to the cardinal points or the angle between two such directions. In geodesy, the angle between the meridian and a given direction, measured from the meridian in both directions from 0 to 90. ; in the sea ... ... Big Encyclopedic Dictionary

Rumb, and (division on the compass circle) ... Russian verbal stress

M. 1. Measure of the angle of the horizon circle, divided into 32 parts. Ott. Compass circle division corresponding to 1/32 of the visible horizon (in nautical navigation). 2. Direction to the points of the visible horizon relative to the cardinal points (from ... ... Modern explanatory dictionary of the Russian language by Efremova

Books

Thirty third point, Maria Golikova. End of the 17th century. Poor young Italians Sergio and Francesco are hired as sailors on a Dutch merchant ship, hoping to find their place in life and earn a piece of bread. But sea -…
Shipbuilding abroad, No. 8, 1975,. Shipbuilding abroad. No. 8 (104) TsNII Rumb 1975 ...

Rumb

the angle between the north or south direction of the magnetic meridian (compass needle) and this direction. The true bearing is counted from the sowing. or south. the direction of the true (astronomical) meridian. The points are counted to the right and left of the meridian, from 0 to 90 °, always indicating a quarter (N-V, N-W, S-W, S-B). For example, azimuth 135 ° corresponds to S.-B. 45 °. Unlike azimuths, bearing points never exceed 90 °, so it is convenient to use them in geodetic calculations.

Geography. A modern illustrated encyclopedia. - M .: Rosman. Edited by prof. A.P. Gorkina. 2006 .

Synonyms:

See what "rumb" is in other dictionaries:

Angle, stroke Dictionary of Russian synonyms. bearing noun, number of synonyms: 2 angle (27) stroke (21) ... Synonym dictionary

Rumb, and (division on the compass circle) ... Russian verbal stress

Books

Thirty third point, Maria Golikova. End of the 17th century. Poor young Italians Sergio and Francesco are hired as sailors on a Dutch merchant ship, hoping to find their place in life and earn a piece of bread. But sea -…

MUNICIPAL BUDGETARY EDUCATIONAL INSTITUTION

"SECONDARY SCHOOL № 18", ACHINSK

PROJECT

on the topic of

"Azimuths, points and miles in geodesy and mathematics"

Draft prepared

pupils of grade 7 "A"

Aisky Leonid and Velger Vyacheslav

mathematics teacher Vinnik V.V.

achinsk, 2016

Content

Introduction

Rumba

Nautical mile

Conclusion

Introduction

Project hypothesis:

Mathematical calculations are necessary when navigating the terrain

Objective :

Show the connection between geodesy and mathematics

Tasks:
1. To get acquainted with the concepts - azimuth, bearing, nautical mile;

2. Find out how these concepts help to navigate the terrain;

3. Summarize the material studied for the design of the reference booklet.

Azimuths concept and meaning in orienteering

Azimuth (designated "Az" or "Az") is the angle measured clockwise between directions to the north and to the landmark. Azimuth is measured in degrees from 0 ° to 360 °. if the geographic meridian is taken as the initial direction, the azimuth is called true; if the magnetic meridian is taken as the initial direction, the azimuth is called magnetic.

When determining the azimuth using the compass, it is necessary to enter a correction for the magnetic declination arising from the mismatch of the geographic and magnetic poles of the earth.

Direction

Azimuth in degrees

north

0 ° or 360 °

northeast

45 °

east

90 °

southeast

135 °

south

180 °

southwest

225 °

west

270 °

northwest

315 °

2. Rumba

Rumb - in marine terminology, this is 1/32 of the full , and also one ofdivisions on a circle (drawn into 32 parts) and, accordingly, one of the directions relative to .

Rumbas as directions have their own names:

The four main rumba:

North, North-North

East, East-East

South, Zuid-South

West, West-West

Four rumba,derived from the main :

North-West North-West, Northwest

North-East -Nord -Ost North-East

South-East Zuid - East - Southeast

South-Wes South-West - South-West

The designations of the points that are 11.25 degrees apart from the main points (1/32 of the full circle) are obtained from the designationsone of the eight points listed above , with additionafter these are the words "shadow" and the names of the main direction to which the bearing deviates.

The designations of points that are 22.5 degrees (1/16 of a full circle) from the main points are obtained from the designationsderivatives from basic points , with additionbefore them the names of the main direction to which the bearing deviates.

AT the circle is divided into 16 parts, there are no shadows; in nautical navigation (navigation) the horizon circumference is divided into 32 points.

3. Nautical mile

Sea mile - used in and.

Originally nautical mile was defined as the length of an arc on the surface of the globe the size of one ... Thus, moving one nautical mile along the meridian roughly corresponds to a change in geographic coordinates by one minute. .

Since the earth is really , and (flattened from the poles), one minute of the meridian corresponds to approximately 1862 m at the pole and 1843 m at the equator (on average about 1852 m). According to the modern definition adopted at the International Hydrographic Conference in Monaco in 1929,international nautical mileis exactly 1852. International nautical mile is 10 .

A nautical mile is not a unit however, by decision , its use is allowed, although not recommended. There is no generally accepted designation; sometimes the abbreviations "NM", "nm" or "nmi" are used). It should be noted that the abbreviation "nm" coincides with the officially accepted designation .

Conclusion

In our work, we set the goal of proving the truth of the hypothesis and showing the connection between geodesy and mathematics. In the process of preparing the work, it was necessary to learn new concepts for us: rumba and miles.

While preparing the project, we learned some interesting historical facts. They consolidated their knowledge on the chosen topic and proved the veracity of their hypothesis. To broaden the horizons of students in the study of geography and mathematics, we have created a booklet.

Sources used:

1.https: //yandex.ru/images/search? Text \u003d nautical% 20mile & img

3. https://otvet.mail.ru/question/83975488

Rumba of the horizon

1. Wind speed and direction

1.1. Wind speed

1.2. Direction of the wind

Books

See what "rumb" is in other dictionaries:

Books

The last

You need to know