Geographic latitude of the place. Geographic coordinates, latitude and longitude, how to determine geographical coordinates from a topographic map. The concept of geographic latitude

Latitude and longitude - coordinates on the globe to help you find a specific place. When writing latitude and longitude, it's worth making sure you're using the correct format and the correct characters to make sure you're understood. You can determine the position of various latitude and longitude points on a map and then write them down. You can write latitude and longitude using only the value of the parallel and meridian. For specific latitude and longitude points, you can write coordinates using degrees, minutes, seconds, and decimals.

Steps

Write down the main values of latitude and longitude

Determine geographic longitude. A meridian is a line of longitude that runs vertically around the globe, from the North Pole to the South Pole. The zero (initial) meridian is the reference point of longitude. This is the zero point. It is also called the Greenwich meridian. When writing longitude, the symbol is used ° to indicate degrees.
- Meridians are counted east and west from zero. When moving east, the value of geographic longitude increases by one degree for each subsequent meridian. You can use the abbreviation "c. etc." ("east longitude"; the letter "E" is used for international designation - East) to indicate the longitude located east of the prime meridian. For example, geographic longitude might be 30°E. (30°E).
- If you move west, then the value of geographic longitude also increases by one degree at each next meridian. The geographical longitude located to the west of the zero meridian is indicated by the abbreviation "z. etc." ("west longitude"; the letter "W" is used for international designation - West). For example, geographic longitude might be 15°W. (15°W).
Determine geographic latitude. Geographic latitude is a horizontal line (parallel) dividing the globe. Parallels stretch from east to west, starting from the equator. The geographic latitude of the equator is 0 degrees. When writing latitude, the symbol used to represent degrees is ° .
- If you move north from the equator, then the geographical latitude increases by 1 degree with each parallel until it reaches 90 degrees. The North Pole is at 90 degrees. Geographic latitude above the equator is indicated by the abbreviation "s. sh.” ("northern latitude"; the letter "N" is used for international designation - North). For example, the geographic latitude may be 15°N. sh. (15°N).
- If you move south from the equator, then the geographic latitude also increases by 1 degree for each successive parallel until it reaches 90 degrees. This is the South Pole. For south latitude, use the abbreviation "s. sh.” (for international designation, the letter "S" is used - South). For example, the geographic latitude might be 30°S. sh. (30°S).
Write down the latitude and longitude coordinates. Pick a point and find out where the lines of latitude and longitude intersect. For example, a point can be found by the coordinates of the parallel 15 ° N. sh. and meridian 30° E. e. When writing coordinates, latitude comes first, then longitude (in international writing they are separated by a comma).
- The geographic latitude and longitude given above are written as 15° N sh. 30° in. (15°N, 30°E).
Determine if the value is negative or positive. In a tenths-degrees-minutes system, north, south, east, and west directions are not used. Instead, positive or negative numbers are used to define a point on the map.
- Remember that the parallels run north or south of the equator. When using tenths to indicate latitude and longitude, positive values are north of the equator and negative values are south. A point with a value of 23.456 will be higher from the equator, and a point with a value of -23.456 will be lower.
- Meridians are located east or west of the prime meridian (Greenwich). Positive values indicate a point east of Greenwich, and negative values indicate a point to the west. For example, a point with a value of 10.234 will be east of the prime meridian, and a point with a value of -10.234 will be west.

Rice. 2 Geographic coordinates

The position of various objects on the Earth's surface can be determined using geographic coordinates. To read the coordinates, a system of points and circles is conventionally plotted on the globe (Fig. 2). Let us introduce a number of definitions. An imaginary line around which diurnal rotation The earth is called the earth's axis. Its points of intersection with the earth's surface are called geographic or true poles: northern PN and southern PS. When a sphere is cut by a plane, a circle is obtained, and a circle is formed on the surface of the sphere. If the cutting plane passes through the center of the ball, then the circle has the largest dimensions and is called big. Circles formed from the section of a ball by planes that do not pass through its center are called small. The circumference of the great circle QQ /, whose plane is perpendicular to the earth's axis, is called equator. It divides the globe into northern and southern hemispheres. Circles of small circles, the planes of which are parallel to the plane of the equator, are called parallels(pp /). The circles of great circles, the planes of which pass through the axis of the Earth, are called geographic or true meridians. Half of the circumference of the PnMPs meridian enclosed between the poles and passing through given point M, call meridian of the observer (place). The PnGPs meridian passing through the astronomical observatory in Greenwich (England) is called Greenwich(initial or zero) meridian. The Greenwich meridian, together with the opposite meridian PnG / Ps, divides the globe into eastern and western hemispheres.

The geographic coordinate system includes two spherical coordinates: latitude and longitude.

Geographic latitude- this is the angle at the center of the Earth between the equatorial plane and a plumb line drawn through a given point (angle MOL, see Fig. 2). Latitude is measured by a meridian arc from the equator to the parallel of a given point. It is measured north or south of the equator from 0 to 90°. If the point is in the northern hemisphere, its latitude is assigned the name N (northern), if in the southern - S (south). Latitude is denoted by a Greek letter "" (fi). Example: j = 45 0 15¢.2 N; j = 55 0 05¢.1 S

Geographic longitude - is the angle at the center of the Earth between the plane of the Greenwich meridian and the plane of the meridian of the given point (angle GOL, see Fig. 2). Longitude is measured by the smaller of the arcs of the equator between the Greenwich meridian and the point meridian and is measured from the Greenwich meridian to the east or west from 0 to 180 °. If the point is in the eastern hemisphere, then the name E (eastern) is attributed to the longitude, if in the western - W (western). Longitude is denoted by a Greek letter "" (lambda). For example: l \u003d 125 0 16¢.9E; l \u003d 105 0 00¢,1W.

Latitude difference and longitude difference. The geographic coordinates of the vessel change as a result of movement. The changes in latitude and longitude of a ship are called latitude and longitude differences. Latitude difference(RSh) of two points on the earth's surface is measured by a meridian arc enclosed between the parallels of these points. Highest value RH can be 180°, which would correspond to the movement of the vessel from one pole to another. If the ship was moving along any one parallel, then RSH is equal to 0°. The calculated RSH is assigned the name “to N” or “to S”, depending on the direction in which the ship was moving. Longitude difference(RD) of two points on the earth's surface is measured by the smaller of the arcs of the equator enclosed between the meridians of these points. Since the smaller of the arcs of the equator is always taken as the difference in longitudes, its value cannot exceed 180 °. If, when adding opposite longitudes, a value greater than 180 ° is obtained, then the addition of up to 360 ° is taken as a taxiway. Such a case may occur when the vessel crosses the 180° meridian. The calculated value of the taxiway is assigned the name of E or W, depending on the direction in which the ship moved. If the northern latitude and eastern longitude are conditionally assigned a plus (+) sign, and the southern latitude and western longitude (-), then the value of RH and RD can be calculated using algebraic formulas:

Rice. 3 Latitude difference and Longitude difference

The sign of the result obtained when calculating by formulas will show the names of RSH and RD. If the addition of up to 360 ° is taken when calculating the RD, then the name of the RD is changed. In order not to be mistaken in the meaning and name of the calculated RSH and RD, one should have a good idea mutual arrangement meridians and parallels on the globe (see Fig. 3,). In practice, it may be necessary to find the coordinates of the point at which the ship arrived, if the coordinates of the point of departure are given, as well as the RS and TW characterizing the position of the point of arrival. Calculations can be made using algebraic formulas.

Geographic latitude

Geographic latitude is determined using parallels. Latitude may be northern (those parallels that are north of the equator) and southern (those parallels that lie south of the equator). The value of latitudes is measured in degrees and minutes. Geographic latitude can have values from 0 to 90 degrees.

Rice. 1. Determination of latitudes

Geographic latitude is the length of the arc in degrees from the equator to the given point.

To determine the latitude of an object, you need to find the parallel on which this object is located.

For example, the latitude of Moscow is 55 degrees and 45 minutes north latitude, it is written as follows: Moscow 55 ° 45 "N; New York latitude - 40 ° 43" N; Sydney - 33°52"S

Geographic longitude

Geographic longitude is determined by meridians. Longitude can be western (from 0 meridian west to 180 meridian) and eastern (from 0 meridian east to 180 meridian). Longitudes are measured in degrees and minutes. Geographic longitude can have values from 0 to 180 degrees.

Geographic longitude is the length of the equatorial arc in degrees from the initial meridian (0 degrees) to the meridian of the given point.

The prime meridian is the Greenwich meridian (0 degrees).

Rice. 2. Determination of longitudes

To determine longitude, you need to find the meridian on which the given object is located.

For example, the longitude of Moscow is 37 degrees and 37 minutes of east longitude, it is written as follows: 37 ° 37 "E; longitude of Mexico City - 99 ° 08" W.

Rice. 3. Geographic latitude and geographic longitude

Geographical coordinates

For exact definition the location of an object on the surface of the Earth, it is necessary to know its geographic latitude and geographic longitude.

Geographical coordinates- quantities that determine the position of a point on the earth's surface using latitudes and longitudes.

For example, Moscow has the following geographic coordinates: 55°45" N and 37°37" E. The city of Beijing has the following coordinates: 39°56′ N 116°24′ E The latitude value is written first.

Sometimes you need to find an object by already given coordinates, for this you must first assume in which hemispheres this object is located.

Bibliography

Main

1. Starting Course Geography: Proc. for 6 cells. general education institutions / T.P. Gerasimova, N.P. Neklyukov. – 10th ed., stereotype. – M.: Bustard, 2010. – 176 p.

2. Geography. Grade 6: atlas. – 3rd ed., stereotype. – M.: Bustard, DIK, 2011. – 32 p.

3. Geography. Grade 6: atlas. - 4th ed., stereotype. – M.: Bustard, DIK, 2013. – 32 p.

4. Geography. 6 cells: cont. cards. – M.: DIK, Bustard, 2012. – 16 p.

Encyclopedias, dictionaries, reference books and statistical collections

1. Geography. Modern illustrated encyclopedia / A.P. Gorkin. – M.: Rosmen-Press, 2006. – 624 p.

Materials on the Internet

1. Federal Institute of Pedagogical Measurements ().

2. Russian Geographic Society ().

Latitude- the angle between the local direction of the zenith and the plane of the equator, counted from 0 to 90 in both directions from the equator. The geographical latitude of points lying in the northern hemisphere (northern latitude) is considered to be positive, the latitude of points in the southern hemisphere is negative. In addition, it is customary to talk about latitudes that are larger in absolute value - as high, and about those close to zero (that is, to the equator) - as about low.

Longitude

Longitude- the angle between the plane of the meridian passing through the given point, and the plane of the initial zero meridian, from which the longitude is calculated. Now on Earth, the zero meridian is the one that passes through the old observatory in the city of Greenwich, and therefore it is called the Greenwich meridian. Longitudes from 0 to 180 ° east of the zero meridian are called eastern, to the west - western. Eastern longitudes are considered to be positive, western - negative. It should be emphasized that, in contrast to latitude, for a system of longitudes, the choice of the reference point (zero meridian) is arbitrary and depends only on the agreement. So, in addition to Greenwich, the meridians of the observatories of Paris, Cadiz, Pulkovo (on the territory of the Russian Empire), etc. were previously chosen as zero.

Height

To fully determine the position of a point three-dimensional space, the third coordinate is needed - height. The distance to the center of the planet is not used in geography: it is convenient only when describing very deep regions of the planet or, on the contrary, when calculating orbits in space.

Within geographical envelope usually applied height above sea level, counted from the level of the "smoothed" surface - the geoid. Such a system of three coordinates turns out to be orthogonal, which simplifies a number of calculations. Altitude above sea level is also convenient in that it is related to atmospheric pressure.

The distance from the earth's surface (up or down) is often used to describe a location, however not serves coordinate due to surface roughness.

Longitude

Longitude- the angle λ between the plane of the meridian passing through the given point, and the plane of the initial zero meridian, from which the longitude is counted. Longitudes from 0° to 180° east of the prime meridian are called east, to the west - west. Eastern longitudes are considered to be positive, western - negative.

Height

To fully determine the position of a point in three-dimensional space, a third coordinate is needed - height. The distance to the center of the planet is not used in geography: it is convenient only when describing very deep regions of the planet or, on the contrary, when calculating orbits in space.

Within the geographic envelope, the "height above sea level" is usually used, measured from the level of the "smoothed" surface - the geoid. Such a system of three coordinates turns out to be orthogonal, which simplifies a number of calculations. Altitude above sea level is also convenient in that it is related to atmospheric pressure.

The distance from the earth's surface (up or down) is often used to describe a location, however not serves coordinate

Geographic coordinate system

The main disadvantage in the practical application of HSC in navigation is the large values angular velocity of this system at high latitudes, increasing up to infinity at the pole. Therefore, instead of HCS, a semi-free CS in azimuth is used.

Semi-free in azimuth coordinate system

The semi-free in azimuth SC differs from the HSC in only one equation, which has the form:

Accordingly, the system has the same initial position that the HCS and their orientation also coincide with the only difference that its axes and are deviated from the corresponding axes of the HCS by an angle for which the equation is valid

The conversion between the HCS and semi-free in the azimuth of the CS is carried out according to the formula

In reality, all calculations are carried out in this system, and then, to issue output information, the coordinates are transformed into the GCS.

Recording formats for geographic coordinates

The WGS84 system is used to record geographic coordinates.

Coordinates (latitude -90° to +90°, longitude -180° to +180°) can be written:

in ° degrees as a decimal fraction (modern version)
in ° degrees and "minutes s decimal
in ° degrees, " minutes and " seconds with a decimal fraction (historical notation)

The decimal separator is always a dot. Positive signs of coordinates are represented by the (in most cases, omitted) sign "+", or by the letters: "N" - north latitude and "E" - east longitude. Negative signs of coordinates are represented either by a "-" sign or by the letters: "S" - southern latitude and "W" - western longitude. Letters can stand both in front and behind.

There are no uniform rules for recording coordinates.

By default, search engine maps show coordinates in degrees with a decimal fraction with "-" signs for negative longitude. On Google maps and Yandex maps, latitude first, then longitude (until October 2012, the reverse order was adopted on Yandex maps: first longitude, then latitude). These coordinates are visible, for example, when laying routes from arbitrary points. The search also recognizes other formats.

In navigators, by default, degrees and minutes are more often shown with a decimal fraction with a letter designation, for example, in Navitel, in iGO. You can enter coordinates in accordance with other formats. The degrees and minutes format is also recommended for maritime communications.

At the same time, the original way of writing with degrees, minutes and seconds is often used. Currently, coordinates can be written in one of many ways or duplicated in two main ways (with degrees and with degrees, minutes and seconds). As an example, the options for recording the coordinates of the sign "Zero kilometer of the roads of the Russian Federation" - 55.755831 , 37.617673 55°45′20.99″ N sh. 37°37′03.62″ E d. / 55.755831 , 37.617673 (G) (O) (I):

55.755831°, 37.617673° -- degrees
N55.755831°, E37.617673° -- degrees (+ additional letters)
55°45.35"N, 37°37.06"E -- degrees and minutes (+ additional letters)
55°45"20.9916"N, 37°37"3.6228"E -- degrees, minutes and seconds (+ additional letters)

Notes

Wikimedia Foundation. 2010 .

See what "Geographic coordinates" are in other dictionaries:

See Coordinates. Mountain Encyclopedia. M.: Soviet Encyclopedia. Edited by E. A. Kozlovsky. 1984 1991 ... Geological Encyclopedia

- (latitude and longitude), determine the position of a point on the earth's surface. Geographical latitude j is the angle between the plumb line at a given point and the plane of the equator, counted from 0 to 90 degrees on both sides of the equator. Geographic longitude l angle ... ... Modern Encyclopedia

Latitude and longitude determine the position of a point on the earth's surface. Geographic latitude? the angle between the plumb line at a given point and the plane of the equator, counted from 0 to 90. in both directions from the equator. Geographic longitude? angle between ... ... Big Encyclopedic Dictionary

Angular values that determine the position of a point on the surface of the Earth: latitude - the angle between the plumb line at a given point and the plane of the earth's equator, measured from 0 to 90 ° (northern latitude north of the equator and southern latitude south); longitude ... ... Marine dictionary

Geographic latitude of the place. Geographic coordinates, latitude and longitude, how to determine geographical coordinates from a topographic map. The concept of geographic latitude

Steps

Write down the main values of latitude and longitude

Geographic longitude

Geographical coordinates

Longitude

Height

Links

see also

See what "Geographical Latitude" is in other dictionaries:

Longitude

Height

Geographic coordinate system

Semi-free in azimuth coordinate system

Recording formats for geographic coordinates

Links

see also

Notes

See what "Geographic coordinates" are in other dictionaries:

Geographic latitude of the place. Geographic coordinates, latitude and longitude, how to determine geographical coordinates from a topographic map. The concept of geographic latitude

Steps

Write down the main values ​​of latitude and longitude

Geographic longitude

Geographical coordinates

Longitude

Height

Links

see also

See what "Geographical Latitude" is in other dictionaries:

Longitude

Height

Geographic coordinate system

Semi-free in azimuth coordinate system

Recording formats for geographic coordinates

Links

see also

Notes

See what "Geographic coordinates" are in other dictionaries:

Write down the main values of latitude and longitude