What are meridians and parallels? How to identify meridians and parallels? Meridians and Parallels of the Ural Mountains

Today, on Earth, there is not a single site that a person has not studied or at least not visited! The more information appeared about the surface of the planet, the more urgent the question of determining the location of a particular object. Meridians and parallels, which are elements of a degree grid, help to find the geographical address of the desired point and facilitate the process of orienting the map.

History of cartography

Humanity did not immediately come to such a simple way to determine the coordinates of the object, as the calculation of its longitude and latitude. Familiar to all of us from school, the main lines gradually appeared in the sources of cartographic knowledge. Below is information about several key stages in the history of the formation of such sciences as geography and astronomy that led civilization to create a modern map with a convenient degree grid.

• One of the "founders" of the natural sciences is considered to be Aristotle, who first proved that our planet has a spherical shape.

• The ancient travelers of the Earth were very observant, and they noticed that in the sky (by the stars), the direction C (north) - 10 (south) can be easily traced. This line is the first "meridian", the analogue of which can be found today on the simplest map.
• Eratosthenes, who is better known as the "father of the science of geography", made a lot of small and large discoveries that influenced the formation of geodesy. He was the first to use the skafis (ancient sundial) to calculate the height of the sun above the territory of different cities and noticed a significant difference in his measurements, which depended on the time of day and season. Eratosthenes revealed the connection between such sciences as geodesy and astronomy, thereby making it possible to carry out many studies and measurements of terrestrial territories with the help of celestial bodies.

Degree Mesh

Numerous meridians and parallels, intersecting on a map or globe, are combined into a geographic grid consisting of "squares". Each cell is bounded by lines that have their own degree. Thus, using this grid, you can quickly find the desired object. The structure of many atlases is constructed in such a way that separate squares are considered on separate pages, which allows you to systematically study any territory. With the development of geographical knowledge, the globe also improved. Meridians and parallels are available on the very first models, which, although they did not contain all the reliable information about the Earth's objects, already gave an idea of the approximate location of the points sought. Modern maps have the required elements, of which the gradient grid consists. With it, coordinates are determined.

Elements of degree grid

• The poles - the North (above) and the South (bottom), are the points at which the meridians converge. They are the places of exit of the virtual line, which is called the axis.
• The Arctic Circles. From them the borders of the polar regions begin. Polar circles (South and North) are located beyond 23 parallels in the direction of the poles.
• Prime Meridian. It divides the Earth's surface into the Eastern and Western hemispheres and has two more names: Greenwich and Primary. All meridians have the same length and on the surface of the globe or a card connect the poles.
• Equator. It is the longest parallel, oriented from the Z (west) to the B (east), which divides the planet into the Southern and Northern Hemispheres. All other lines parallel to the equator have different sizes - their length decreases to the poles.
• Tropics. There are also two of them - Capricorn (South) and Cancer (North). The tropics are located at the 66th parallel to the south and north of the equator.

How to determine the meridians and parallels of the desired point?

Any object on our planet has its latitude and longitude! Even if it is very-very small or, conversely, quite large! Determine the meridians and parallels of the object and find the coordinates of the point - the same action, because it is the degree of the main lines that determines the geographical address of the desired territory. Below is a plan of action that can be used to calculate the coordinates.

Algorithm for determining the geographic address of an object on a map

1. Specify the correctness of the geographical name of the object. Annoying mistakes happen because of banal inattention, for example: the student made a mistake in the name of the desired point and determined the wrong coordinates.
2. Prepare an atlas, a sharp pencil or a pointer and a magnifying glass. These tools will help to more accurately determine the address of the desired object.
3. Select the largest map from the atlas that has the desired geographic point. The smaller the scale of the map, the more errors there are in the calculations.
4. Determine the ratio of the object to the main elements of the grid. The algorithm of this procedure is presented after the item: "Calculation of the size of the territory".
5. If the desired point is not directly on the line indicated on the map, then find the nearest ones that have a numerical designation. The degree of the lines is usually indicated along the perimeter of the map, less often on the equator line.
6. In determining the coordinates, it is important to find out how many degrees of the parallels and meridians on the map are located and to correctly calculate the unknowns. It is necessary to remember that the elements of the degree grid, in addition to the main lines, can be drawn through any point on the surface of the Earth.

Calculating the size of the territory

• If it is necessary to calculate the object's dimensions in kilometers, then it is necessary to remember that the length of one degree of grid lines is -111 km.
• To determine the length of an object from W to E (in case it is completely located in one of the hemispheres: East or West) it is enough from the larger latitude of one of the extreme points, subtract the smaller and multiply the result by 111 km.
• If it is necessary to calculate the length of the territory from N to S (only if it is all located in one of the hemispheres: Southern or Northern), then it is necessary from the greater degree of longitude of one of the extreme points, subtract the smaller, then multiply the sum by 111 km .
• If the Greenwich meridian passes through the territory of the object, then to calculate its length from W to E, the latitudes of the extreme points of this direction are added, then their sum is multiplied by 111 km.
• If there is an equator on the territory of the identified object, then to determine its length from N to S, it is necessary to add the degrees of longitude of the extreme points of this direction, and multiply the resulting sum by 111 km.

How to determine the ratio of the object to the main elements of the degree grid?

• If the object is below the equator, its latitude will be only southern, if higher - northern.
• If the desired point is located to the right of the initial meridian, then its longitude will be eastern, if it is to the left - the western one.
• If the object is above the 66th degree of the north or south parallel, it enters the corresponding polar region.

Determining the coordinates of mountains

Since many mountain systems are of great length in different directions, and meridians and parallels crossing such objects have different degrees, the process of determining their geographic address is accompanied by many questions. Below we propose options for calculating the coordinates of the high Eurasian territories.

Caucasus

The most picturesque mountains are located between the two water areas of the mainland: from the Black Sea to the Caspian Sea. The meridians and parallels of the Caucasian mountains have different degrees, so what are the decisive factors for the address of this system? In this case, we focus on the highest point. That is, the coordinates of the mountain system Caucasus is the geographic address of the peak Elbrus, which is equal to 42 degrees 30 minutes north latitude and 45 degrees east longitude.

Himalayas

The highest mountain system on our continent is the Himalayas. Meridians and parallels of varying degrees cross this object as often as the above. How to correctly determine the coordinates of this system? We do the same as in the case of the Ural Mountains, we focus on the highest point of the system. Thus, the coordinates of the Himalayas coincide with the address of the peak of Jomolungma, and this is 29 degrees 49 minutes north latitude and 83 degrees 23 minutes and 31 seconds east longitude.

The Ural Mountains

The longest on our continent is the Ural Mountains. Meridians and parallels, having different degrees, cross this object in different directions. To determine the coordinates of the Ural mountains it is necessary to find their center on the map. This point will be the geographical address of this object - 60 degrees north latitude and the same eastern longitude. A similar method of determining the coordinates of mountains is acceptable for systems that have a large length in one direction or both.