The position of each point on earth's surface determine its coordinates: latitude and longitude (Fig. 3).

latitude called the angle formed by a plumb line passing through a given point on the surface of the Earth, and the plane of the equator (in Fig. 3 for point M, the MOS angle).

At whatever point on the globe the observer is, his force of gravity will always be directed towards the center of the Earth. This direction is called sheer, or vertical.

Latitude is measured by an arc of the meridian from the equator to the parallel of a given point in the range from 0 to 90 ° and is denoted by the letter f. Thus, the geographic parallel eabq is the locus of points having the same latitude.

Depending on which hemisphere the point is in, the latitude is given the name northern (N) or southern (S).

longitude the dihedral angle between the planes of the initial meridian and the meridian of a given point is called (in Fig. 3 for the point M, the angle AOC) . Longitude is measured by the smaller of the arcs of the equator between the initial meridian and the meridian of a given point in the range from 0 to 180 ° and is denoted by the letter l. Thus, the geographic meridian PN MCPs is the locus of points having the same longitude.

Depending on which hemisphere the point is in, the longitude is called east (O st) or west (W).

Latitude difference and longitude difference

During the voyage, the ship continuously changes its position on the surface of the Earth, therefore, its coordinates also change. The magnitude of the change in latitude Af, obtained when the ship moves from the point of departure MI to the point of arrival C1, is called latitude difference(RSh). RSH is measured by the meridian arc between the parallels of the departure and arrival points M1C1 (Fig. 4).

Rice. four

The name of the RSH depends on the location of the parallel of the point of arrival relative to the parallel of the point of departure. If the parallel of the point of arrival is located to the north of the parallel of the point of departure, then the RS is considered to be made to N, and if to the south, then to S.

The value of the change in longitude Al, resulting from the passage of the vessel from the point of departure M1 to the point of arrival C2, is called longitude difference(RD). The taxiway is measured by the smaller arc of the equator between the meridians of the point of departure and the point of arrival of the MCN (see Fig. 4). If during the passage of the ship the east longitude increases or the west decreases, then the taxiway is considered to be made to O st, and if the east longitude decreases or the west increases, then to W. To determine the RSH and TW, use the formulas:

РШ = φ1 - φ2; (one)

RD = λ1 - λ2 (2)

Where φ1 is the latitude of the departure point;

φ2 - latitude of the point of arrival;

λ1 - longitude of departure point;

λ2 - longitude of the arrival point.

In this case, northern latitudes and eastern longitudes are considered positive and a plus sign is assigned to them, and southern latitudes and western longitudes are negative and a minus sign is assigned to them. When solving problems according to formulas (1) and (2), in the case of positive results of RS, it will be made to N, and RD - to O st (see example 1), and in the case of negative results of RS, it will be to S, and RD - to W (see example 2). When obtaining a RD result of more than 180° with a negative sign, 360° must be added (see example 3), and if the RD result is greater than 180° with a positive sign, 360° must be subtracted (see example 4).

Example 1 Known: φ1 = 62°49" N; λ1 = 34°49" O st ; φ2 = 72°50"N; λ2 = 80°56"Ost.

Find RSH and RD.

Solution.

Example 2. Known: φ1 = 72°50" N; λ1 = :80°56"O st: φ2 = 62 O st 49"N;

Find RSH and RD.

There are many different coordinate systems. All of them are used to determine the position of points on the earth's surface. This includes mainly geographic coordinates, flat rectangular and polar coordinates. In general, it is customary to call coordinates angular and linear quantities that define points on a surface or in space.

Geographical coordinates- these are angular quantities - latitude and longitude, which determine the position of a point on the globe. Geographic latitude is the angle formed by the plane of the equator and a plumb line at a given point on the earth's surface. This angle value shows how far a particular point on the globe is north or south of the equator.

If the point is located in the Northern Hemisphere, then its geographical latitude will be called the northern latitude, and if in the Southern Hemisphere - the southern latitude. The latitude of points located on the equator is zero degrees, and at the poles (North and South) - 90 degrees.

Geographic longitude is also an angle, but formed by the plane of the meridian, taken as the initial (zero), and the plane of the meridian passing through the given point. For the uniformity of the definition, it was agreed to consider the meridian passing through the astronomical observatory in Greenwich (near London) as the initial meridian and call it Greenwich.

All points located to the east from it will have eastern longitude (up to the meridian of 180 degrees), and to the west of the initial one - western longitude. The figure below shows how to determine the position of point A on the earth's surface if its geographical coordinates (latitude and longitude) are known.

Note that the difference in longitudes of two points on Earth shows not only their relative position with respect to the zero meridian, but also the difference in these points at the same moment. The fact is that every 15 degrees (24th part of the circle) in longitude is equal to one hour of time. Based on this, it is possible to determine the difference in time at these two points by geographical longitude.

For example.

Moscow has a longitude of 37°37′ (East), and Khabarovsk -135°05′, that is, lies to the east of 97°28′. What time do these cities have at the same moment? Simple calculations show that if it is 13:00 in Moscow, then it is 19:30 in Khabarovsk.

The figure below shows the design of the sheet frame of any map. As can be seen from the figure, in the corners of this map, the longitude of the meridians and the latitude of the parallels that form the frame of the sheet of this map are signed.

On all sides, the frame has scales divided into minutes. For both latitude and longitude. Moreover, each minute is divided by dots into 6 equal sections, which correspond to 10 seconds of longitude or latitude.

Thus, in order to determine the latitude of any point M on the map, it is necessary to draw a line through this point parallel to the lower or upper frame of the map, and read the corresponding degrees, minutes, seconds on the latitude scale to the right or left. In our example, point M has a latitude of 45°31’30”.

Similarly, drawing a vertical line through point M parallel to the lateral (closest to this point) meridian of the border of this sheet of the map, we read the longitude (east) equal to 43 ° 31'18 ".

Drawing a point on a topographic map according to given geographical coordinates.

Drawing a point on the map according to the given geographical coordinates is carried out in the reverse order. First, the indicated geographical coordinates are found on the scales, and then a parallel and perpendicular to the line. Intersecting them on will show the point with the given geographic coordinates.

Based on the book "The map and the compass are my friends."
Klimenko A.I.

And to find the exact location of objects on the earth's surface allows degree network- a system of parallels and meridians. It serves to determine the geographical coordinates of points on the earth's surface - their longitude and latitude.

Parallels(from Greek. parallelos- walking nearby) - these are lines conditionally drawn on the earth's surface parallel to the equator; equator - a line of section of the earth's surface depicted by a plane passing through the center of the earth perpendicular to the axis of its rotation. The longest parallel is the equator; the length of the parallels from the equator to the poles decreases.

meridians(from lat. meridianus- midday) - lines conditionally drawn on the earth's surface from one pole to the other along the shortest way. All meridians are equal in length. All points of a given meridian have the same longitude, and all points of a given parallel have the same latitude.

Rice. 1. Elements of a degree network

Geographic latitude and longitude

Geographic latitude of the point is the value of the meridian arc in degrees from the equator to the given point. It varies from 0° (equator) to 90° (pole). Distinguish between northern and southern latitudes, abbreviated n. and y.sh. (Fig. 2).

Any point south of the equator will have a south latitude, and any point north of the equator will have a north latitude. To determine the geographical latitude of any point means to determine the latitude of the parallel on which it is located. On maps, the latitude of parallels is signed on the right and left frames.

Rice. 2. Latitude

Geographic longitude of a point is the magnitude of the parallel arc in degrees from the prime meridian to the given point. The initial (zero, or Greenwich) meridian passes through the Greenwich Observatory, located near London. To the east of this meridian, the longitude of all points is east; to the west, it is west (Fig. 3). Longitude varies from 0 to 180°.

Rice. 3. Geographic longitude

To determine the geographical longitude of any point means to determine the longitude of the meridian on which it is located.

On the maps, the longitude of the meridians is signed on the upper and lower frames, and on the map of the hemispheres - on the equator.

The latitude and longitude of any point on Earth make up its geographical coordinates. Thus, the geographic coordinates of Moscow are 56°N. and 38°E

Geographic coordinates of cities in Russia and CIS countries

City	Latitude	Longitude
Abakan	53.720976	91.44242300000001
Arkhangelsk	64.539304	40.518735
Astana(Kazakhstan)	71.430564	51.128422
Astrakhan	46.347869	48.033574
Barnaul	53.356132	83.74961999999999
Belgorod	50.597467	36.588849
Biysk	52.541444	85.219686
Bishkek (Kyrgyzstan)	42.871027	74.59452
Blagoveshchensk	50.290658	127.527173
Bratsk	56.151382	101.634152
Bryansk	53.2434	34.364198
Velikiy Novgorod	58.521475	31.275475
Vladivostok	43.134019	131.928379
Vladikavkaz	43.024122	44.690476
Vladimir	56.129042	40.40703
Volgograd	48.707103	44.516939
Vologda	59.220492	39.891568
Voronezh	51.661535	39.200287
Grozny	43.317992	45.698197
Donetsk, Ukraine)	48.015877	37.80285
Yekaterinburg	56.838002	60.597295
Ivanovo	57.000348	40.973921
Izhevsk	56.852775	53.211463
Irkutsk	52.286387	104.28066
Kazan	55.795793	49.106585
Kaliningrad	55.916229	37.854467
Kaluga	54.507014	36.252277
Kamensk-Uralsky	56.414897	61.918905
Kemerovo	55.359594	86.08778100000001
Kyiv(Ukraine)	50.402395	30.532690
Kirov	54.079033	34.323163
Komsomolsk-on-Amur	50.54986	137.007867
Korolev	55.916229	37.854467
Kostroma	57.767683	40.926418
Krasnodar	45.023877	38.970157
Krasnoyarsk	56.008691	92.870529
Kursk	51.730361	36.192647
Lipetsk	52.61022	39.594719
Magnitogorsk	53.411677	58.984415
Makhachkala	42.984913	47.504646
Minsk, Belarus)	53.906077	27.554914
Moscow	55.755773	37.617761
Murmansk	68.96956299999999	33.07454
Naberezhnye Chelny	55.743553	52.39582
Nizhny Novgorod	56.323902	44.002267
Nizhny Tagil	57.910144	59.98132
Novokuznetsk	53.786502	87.155205
Novorossiysk	44.723489	37.76866
Novosibirsk	55.028739	82.90692799999999
Norilsk	69.349039	88.201014
Omsk	54.989342	73.368212
Eagle	52.970306	36.063514
Orenburg	51.76806	55.097449
Penza	53.194546	45.019529
Pervouralsk	56.908099	59.942935
Permian	58.004785	56.237654
Prokopyevsk	53.895355	86.744657
Pskov	57.819365	28.331786
Rostov-on-Don	47.227151	39.744972
Rybinsk	58.13853	38.573586
Ryazan	54.619886	39.744954
Samara	53.195533	50.101801
St. Petersburg	59.938806	30.314278
Saratov	51.531528	46.03582
Sevastopol	44.616649	33.52536
Severodvinsk	64.55818600000001	39.82962
Severodvinsk	64.558186	39.82962
Simferopol	44.952116	34.102411
Sochi	43.581509	39.722882
Stavropol	45.044502	41.969065
Sukhum	43.015679	41.025071
Tambov	52.721246	41.452238
Tashkent (Uzbekistan)	41.314321	69.267295
Tver	56.859611	35.911896
Tolyatti	53.511311	49.418084
Tomsk	56.495116	84.972128
Tula	54.193033	37.617752
Tyumen	57.153033	65.534328
Ulan-Ude	51.833507	107.584125
Ulyanovsk	54.317002	48.402243
Ufa	54.734768	55.957838
Khabarovsk	48.472584	135.057732
Kharkov, Ukraine)	49.993499	36.230376
Cheboksary	56.1439	47.248887
Chelyabinsk	55.159774	61.402455
Mines	47.708485	40.215958
Engels	51.498891	46.125121
Yuzhno-Sakhalinsk	46.959118	142.738068
Yakutsk	62.027833	129.704151
Yaroslavl	57.626569	39.893822

Measured from 0° to 90° either side of 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. It is customary to speak of latitudes close to the poles as high, and about those close to the equator - as about low.

Due to the difference in the shape of the Earth from the ball, the geographical latitude of the points differs somewhat from their geocentric latitude, that is, from the angle between the direction to a given point from the center of the Earth and the plane of the equator.

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 "altitude 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 practical application The GCS in navigation is the large values ​​of the 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.

On the maps search engines by default, the coordinates are shown 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 default navigators, degrees and minutes are more often shown with a decimal fraction with 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)

Links

• Geographic coordinates of all cities on Earth (English)
• Geographical coordinates of the settlements of the Earth (1) (eng.)
• Geographical coordinates of the settlements of the Earth (2) (eng.)
• Converting coordinates from degrees to degrees/minutes, to degrees/minutes/seconds and vice versa
• Converting coordinates from degrees to degrees/minutes/seconds and vice versa

see also

Notes

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• Coat of arms of Lviv
• AIESEC

See what "Geographic coordinates" are in other dictionaries:

Geographical coordinates- see Coordinates. Mountain Encyclopedia. M.: Soviet Encyclopedia. Edited by E. A. Kozlovsky. 1984 1991 ... Geological Encyclopedia

GEOGRAPHICAL COORDINATES- (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

GEOGRAPHICAL COORDINATES- 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

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