Degree grid: parallels, equator, meridians, prime meridian. Graticule

Meridians and parallels

Meridians and parallels
coordinate lines on a map or globe. Meridians are lines of constant longitude that pass through both poles of the planet and indicate the direction "north - south", and parallels are lines of constant latitude that run parallel to the equator in the direction "west - east". Intersecting, these lines form a grid of geographical coordinates on the map. Usually, integer meridians and parallels are drawn, but for accurate drawing and removal of coordinates, the grid can be thickened to minutes (and on large-scale maps, even to seconds). To do this, the cards have a minute frame, where fractions of degrees are marked. Depending on the method of definition, astronomical, geodesic, geographic and geomagnetic meridians and parallels are distinguished, and on the celestial sphere, respectively, celestial meridians and parallels.

Geography. Modern illustrated encyclopedia. - M.: Rosman. Under the editorship of prof. A. P. Gorkina. 2006 .

See what "meridians and parallels" are in other dictionaries:

Geographic Encyclopedia

Small circles of the sphere, composed by its intersection with a plane parallel to some basic plane (horizon, equator, ecliptic); otherwise a circle, all points of which have equal latitude, declination, or altitude. Daily P. stars small circles, ... ... encyclopedic Dictionary F. Brockhaus and I.A. Efron

- (historical) The initial concept of K. can be found even among savages, especially those living along the banks and about you and having a more or less clear idea of \u200b\u200bthe areas surrounding their territory. Travelers who questioned the Eskimos of S. America and ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

Mappings of the entire surface of the earth's ellipsoid (See Earth's ellipsoid) or any part of it onto a plane, obtained mainly for the purpose of constructing a map. Scale. K. items are built on a certain scale. Reducing mentally ... ... Great Soviet Encyclopedia

An example of a map projection Mercator projection A map projection is a mathematically defined way of displaying the surface of an ellipsoid on a plane. The essence of projections is connected with the fact that the figure of the Earth ... Wikipedia

An example of a map projection Mercator projection A map projection is a mathematically defined way of displaying the surface of an ellipsoid on a plane. The essence of the projections is related to the fact that the figure of the Earth is an ellipsoid that is not deployable in ... ... Wikipedia

Mapping of the entire surface of the earth's ellipsoid or any part of it onto a plane, obtained mainly for the purpose of building a map. K. p. draw on a certain scale. Mentally reducing the earth's ellipsoid to Mraz, one gets its geometric. model ... ... Mathematical Encyclopedia

Meridian(s) meridians and parallels coordinate lines on a map or globe. Meridians are lines of constant longitude that pass through both poles of the planet and indicate the direction "north - south", and parallels are lines of constant latitude that go ... ... Geographic Encyclopedia

Meridians and parallels are coordinate lines on a map or globe. Meridians are lines of constant longitude that pass through both poles of the planet and indicate the direction "north - south", and parallels are lines of constant latitude that run parallel ... ... Geographic Encyclopedia

Books

Grebenshchikov Boris Borisovich. Few rock musicians have not only reached the heights of fame, but also studied everything related to the work of their predecessors and colleagues so thoroughly. Since 2005, Boris Grebenshchikov has been leading ...

Work with text and work with the atlas p.22.

Students are divided into groups and answer questions.

- What are meridians?

What do they look like and why are they called that?

- The length of the meridians.

– What are parallels?

Why are they called that, what do they look like?

is the length of the parallels.

Teacher: Guys, what did you learn about parallels?

Students response.

Parallels are lines that are conventionally drawn along the surface of the earth parallel to the equator. Do you remember what the equator is? Show on the map and on the globe. At each point, the parallel points east and west. Parallels are circles that decrease in length from the equator to the poles. Do you remember what a pole is? The longest parallel is the equator. Its length is 40,000 km. All parallels are circles, the length of which decreases from the equator to the poles. On the map of the hemispheres, parallels are curved lines (arcs), and the equator is a straight line.

Meridians. Translated into Russian, the word "Meridian" means "midday line". Its direction coincides with the direction of the shadow from objects at noon. If you go all the time in the direction of this shadow. You will definitely come to north pole, and in reverse side- to the South.

Meridians are the shortest lines conventionally drawn on the surface of the earth from one geographic pole to another. All meridians are semicircles, converge at the poles and have the same length. On the physical map hemispheres the median meridian is a straight line, and the rest are arcs.

Teacher: Parallels and meridians are drawn through a certain number of degrees.

Work with maps and atlases.

Teacher: Find the equator on a physical map and on a globe. On the contour map mark the equator. He shares Earth into two hemispheres (Northern and Southern). The parallels are measured from the equator. Parallels 10, 20, ... 80 degrees of the Northern or Southern Hemisphere.

Label the parallel 10 degrees of the Northern Hemisphere and 20 degrees of the Southern Hemisphere.

Parallels are signed in a circle on the map of the hemispheres and on the meridian (zero) on the globe.

Teacher: By agreement between the countries, the meridian passing through the Greenwich Observatory in the suburbs of London is considered the initial meridian. Therefore, this meridian is also called the Greenwich meridian. On the map, it is shown with a bolder line than the rest of the meridians.

Select the prime meridian on the map. It divides the globe into two hemispheres (Western and Eastern). The meridians are signed at the equator.

We complete task 43 p. 36.

Teacher: What are parallels and meridians for?

Students: For orientation, determine and indicate the location of various geographical objects on the surface of the Earth.

Teacher: Correctly. The ancient Greek scientist Eratosthenes, who lived in 276-194. BC e., first suggested applying to images earth's surface conditional lines - parallels and meridians.

Determination of directions by meridians and parallels.

Teacher: What do we know. What directions show conditional lines.

Students: Parallels - West, East.

Meridians - north, south.

Teacher: At each point, the parallel is perpendicular to the meridian. Therefore, if you stand on the ground facing north, in the direction of the meridian, spread your arms to the sides, then they will indicate the direction of the parallels, i.e. West East.

The main and intermediate sides of the horizon are determined by meridians and parallels.

In what direction is Cairo from St. Petersburg?
In what direction is Moscow from St. Petersburg?
In what direction is the Red Sea from Moscow?

With the help of conditional lines, you can determine not only directions, but also indicate the position of parts of territories, objects. To determine, for example, the northern and southern parts of Australia, you need to put a pointer on the map along a parallel that runs approximately in the middle of the mainland. To the north of the pointer will be the northern part, and to the south - the southern. How do you define Western and Eastern Australia.

Today, our associations associated with travel have changed a lot. "Unlucky Notes", "Eagle and Tails" against the backdrop of the cheapness of All Inclusive compared to the Soviet ones did their job. Does anyone now remember about "parallels, meridians"? Well, at least a song, right?

Okay, let's remember. Only cities and countries will not flicker - surprisingly, but the parallels with the meridians and next to us pass :)

Have you guessed what we're talking about yet? ;)
Then let's start from afar.
As a child, I had a globe on my desk. How to read Jules Verne without a globe?!
And now the hand does not rise to buy this invention - more a luxury item. And, as it were, irrelevant in the age of Google maps and Yandex satellite.

But I'm not talking about the globe. The journey in search of Captain Grant made the imaginary lines on the globe real, almost tangible. Man's addiction to imaginary lines is quite understandable, because they symbolize the elusive mystery of Being. Again, pirate maps, treasures and adventures. All thirty-three pleasures. Just the silhouette of a steering wheel or the ringing of a ship's bell already triggers the imagination and makes our hearts beat! This is not a booking with a choice between BB, HB and AI.

But the Caribbean is too far away, the pirates are too long ago, and all this, connected together by the movie business, turns into a fantasy, killing the very real romance of distant wanderings. And if you are asked what parallel Cheboksary stands on, some will be surprised: "Well, do we have parallels?"
And when they find out that the 56th parallel runs a little to the south, they will say in disappointment: "Ah, well, I thought so, where can we ...".

Well, here it is, the 56th parallel, here, look. Precisely 56° northern latitude(We are used to integer values, but nature doesn’t care about them, just like city planners!):

Panorama from DCP 56°N 47°E (click to view full size)

There are people for whom the awl still works, and even too much - and they invent "home" parallels with the meridians (known to some as the Hartman grid), which pass every two meters, and even teach how to properly position the bed in order to don't hit the nodes. It takes a psychic to find these lines and knots. But it's not scary, even I can do it, and even without a frame :). And everyone can, if they try.

Only here is the incident: it is customary to take the distance between the lines the same everywhere. I have never heard that the grid of Hartman and Murmansk differed from the grid, for example, in Odessa! ;) Apparently, psychics, even graduates, do not always remember the features of the geometry of the sphere. Meanwhile, you can stretch a square grid of figs onto a globe!
But let's leave the glitches of psychics aside and return to geography.
With the equator and with all the meridians it is easier: one degree when moving along them is the same everywhere and is approximately 40000/360=111 km. And one minute of arc, respectively, is 60 times less: 1.852 km.
By the way, who knows what this number is? My friends, this is a nautical mile! Have you heard of such a unit of distance?

So, with latitude, everything is clear. To get one degree north or south, you have to walk 111 km.
And how many from one meridian to another? At the equator - the same 111 km. And at the pole, obviously, zero! Because there all the meridians converge. And you can commit trip around the world" around the pole, while crossing all time zones in a few steps!
At our latitude from one meridian to another - only 62 kilometers with a tail.
Therefore, the mysterious points of intersection of parallels and meridians are not so far from us.
And these nodes are beautifully called: confluent points.
Immediately there is a desire to find them and visit. Why, ask? Well, you're not original. Vysotsky has already managed to ask you:

I asked you: "Why are you going uphill? -
And you went to the top, and you rushed into battle. -
After all, Elbrus can be seen great from an airplane ... "
You laughed and took it with you.

We went too. By the will of strange people who are ready to travel along virtual lines and their intersections, and was born international project Degree Confluence Project:

Briefly, I already wrote about those points that are located on the territory of Chuvashia (there are only three of them), c.
I visited one of them as soon as I bought a communicator with GPS. This closest point to us with coordinates 57°N 47°E is located near the village of Ishley, on the other side of the village of Khachiki. You can drive close to the point by car both through Ishley and through Khachiki:

A panorama from the point is given above, and a visit to the point is described on the DCP website.

We see that there are still many white spots on the territory of Russia (points not visited by DCP users). This does not mean that no one has ever been there, it just means that no one, even if they knew the coordinates, bothered to tell about it on the DCP project :)
Surprisingly, the lion's share of points in the European part of Russia was "discovered" by the same traveler - Vladimir Chernorutsky. Today he has 131 visited points in 5 countries!

And I must say that the points can be in the most remote and inaccessible places - taiga, swamps, and even in the middle of a lake or river. In the latter case, enthusiasts specially take an inflatable boat with them and pick up Right place already on the water! The nearest water point is on the Volga near Zvenigovo:

While searching for my first confluence point, I did not know anything about the Degree Confluence Project, and I safely forgot the note I read about it on Habré. But after visiting I remembered, and easily found the appropriate site. It turned out that at this point I was only the third visitor.
But, to my great surprise, on the map of Russia I found a hitherto undiscovered point N57° E47° in Kirov region, only 180 km from my house! Well, seven miles is not a detour, as they say.
Just like , I am extremely lucky. I managed to become the discoverer of the point, ahead of the competitor by literally three days!

It took a long time to arrive, I was almost late. I chose a relatively free day, and drove along the route Cheboksary - Yoshkar-Ola - Sanchursk and another 16 km, through the village with beautiful name Smetanino (almost visiting Uncle Fyodor with Matroskin;)). Unfortunately, the last 35 km of the road (before and after Sanchursk) turned out to be a real off-road rally, suitable only for 4x4 lovers, since only memories and asphalt pits remained from the road. This segment of the journey took almost two hours! Fortunately, now the road has been repaired there, so you can drive without fear:

I had to leave the car at the nearest point on the road and walk about two kilometers through a swampy, abandoned field to a forest visible on the horizon, where the intersection point is located:

The point itself is located in the forest, fortunately not very far:

Don't forget your mosquito gear if you want to visit this place in summer! I was never able to shoot the planned panorama; hands and face were black under a layer of mosquitoes and horseflies. And here is the point. In the picture at the beginning of the post, you see a mosquito climbing into the lens, and a communicator spattered with fresh blood. So it goes! But we got:

Such geographical travels, such discoveries. It would seem that interesting? Taiga, horseflies - romance! :)
There were no more undiscovered points nearby, except in the wilds of the Kirov region and no closer than 300-400 km.
But it is not necessary to climb into the taiga far away.
It would be possible to organize tourism in the nearest points, why not? It's time to revive the romance!

By the way, one of my colleagues from Togliatti, even before the era of GPS, carefully studied maps and found out that the middle of the Volga is located near Cheboksary!
Hey city officials! Instead of constructing pathos monuments with outstretched arms and marking the “zero mile” for tourists on Red Square, it would be better to mark the middle of the Volga. And then you tell where you are from, and you have to clarify that Cheboksary is not where pasties and Cheburashka are, but between Gorky and Kazan. But now you can proudly declare: right in the center of the Volga!

Big and small trips(cm.

In the form of what lines are the meridians and parallels drawn on the globe?

1. Lines of meridians and parallels on various maps. On a map of the world, compiled by combining the strips of the globe along the equator, the meridians are straight lines of equal size. Parallels drawn perpendicular to them are also straight lines. Their length from the equator to the poles is not shortened, as on the globe, but remains the same. (What does this say?)
The equator and the median meridian of each hemisphere are shown as straight lines on the map of the hemispheres. Other meridians and parallels are curved lines of various lengths. From the middle meridian to the edges, the length of the meridians increases. (What does this say?)
On the map of Kazakhstan, the parallels are shown as arcs of circles. The meridians are represented by straight lines approaching the top of the map.
The map frame has longitude and latitude. On the map of the hemispheres, longitude is shown at the points of intersection of the meridians with the equator.
Meridians and parallels on the globe and maps pass through the same number of degrees (determine how many degrees they are shown on the globe, the map of the hemispheres and the map of Kazakhstan). Therefore, grids formed by changing the lines of meridians and parallels are called degree grids.

2. With the help of meridian lines and parallels, it is very easy to identify on the map geographical coordinates. To do this, you first need to find out between which parallels of latitude and meridians of longitude the desired point is located. For example, the point is between 40° and 45° north latitude, 70° and 75° east longitude (Fig. 32). To more accurately define latitude on the map, using a ruler, we measure the distance (AB) between the two parallels, as well as the distance between the lower parallel and the point H (AN). Segment on the map AB equals 5°.

Rice. 32. Definition of a coordinate point.

To the distance AN Add 40 degrees in degrees. If instead AN we would measure the HV and subtract this distance in degrees from 45 °, then we would still get the same result.
Longitude on the map is determined by the same method. Measure the segments SD and CH with a ruler.

We add 70 ° to the obtained value in degrees and get the longitude of the point H. Just as in determining the line of latitude, instead of the segment CH segment can be measured DN. Then subtract the value obtained from 75°.

Rice. 33. Parts of degree grids on various maps.

1. According to Figure 33, determine which maps each degree grid belongs to?

2. Find on the map of the hemispheres a point indicated by only one of the coordinates.

3. On the map of Kazakhstan, determine the approximate geographical coordinates of your area.