Globe with Latitude and Longitude
What is Latitude?
In the subject geography, the latitude is the distance on the earth’s surface, north or south of the Equator. It is expressed in an angular measurement from 0° at the Equator to 90°, North or South.
The Southern latitudes can be expressed as a negative number where -90° is at the South Pole. Lines of the latitude run parallel to the Equator. Latitude, as well as longitude, can be used together to specify the precise location on the Earth.
What is Longitude?
Longitude is the measurement of the location of east or the west of the prime meridian at Greenwich. It is measured also in degrees, minutes, as well as seconds. The Prime Meridian and then another line from Earth’s centre to any point elsewhere on the Equator.
Longitude is measured 180° from both east as well as west of the prime meridian. Meridians are plotted and also drawn from one pole to another pole where they meet.
How many latitudes and longitudes are there
There are a total of 181 latitudes, ninety north, ninety south, and one is the equator.
There is a total of 360 longitudes. The Prime meridian, 179 east, the longitude of 180 degrees, and also the 179 west.
The western longitude is at 180W and the eastern longitude is at 180E. Both the longitudes are identical.
It is referred to as the 180th meridian as well as the international dateline.
The total number of latitudes is also 180 and the total number of longitudes is 360.
Why are Latitudes and Longitudes Drawn on the Globe?
In order to locate every place accurately on the globe, a network of lines is drawn on the globe. The horizontal lines are called the lines of the latitudes and the vertical lines are called the lines of the longitudes.
These latitudes and the longitudes intersect each other at the right angles and create a network called a grid or a graticule. The latitude is an angle that ranges from zero degrees at the equator to ninety degrees from the north to the south at the poles.
The lines of constant latitude or the parallels run from east to west as circles parallelly to the equator. The latitudes are used together with the longitudes to specify the exact location of the features on the surface of the earth.
Important Latitudes and Longitudes
Important latitudes
Tropic of Cancer- At a position of 23° 26' N. Passes through countries like Mexico, The Bahamas, Mauritania, Mali, Algeria, Niger, Libya, Egypt, Saudi Arabia, UAE, Oman, India, Bangladesh, Myanmar, China, and Taiwan
Tropic of Capricorn- At a position of 23° 26' S. Passes through countries like Namibia, Botswana, South Africa, Mozambique, Madagascar, Australia, Chile, Argentina, Paraguay, Brazil, French Polynesia, New Caledonia, Fiji, and the Cook Islands
Arctic Circle- At a position of 66° 33' N. Passes through countries like Norway, Sweden, Finland, Russia, USA (Alaska), Canada, Denmark (Greenland), and Iceland
Antarctic Circle- At a position of 66° 33' S. Passes through countries like Territories on the Antarctic claimed by Australia, France, New Zealand, Argentina, Chile, and the UK
The Equator- At a position of 0°. Passes through countries like Ecuador, Colombia, Brazil, Sao Tome e Príncipe, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Somalia, and Indonesia
Important Longitudes
Prime Meridian- At a position of 0° longitude. Passes through countries like UK, France, Spain, Algeria, Mali, Burkina Faso, Tongo, and Ghana
International Date Line- At a position of 180° E/W longitude. Passes through countries like the Mid-Pacific Ocean
Continental Drift
The theory that all the continents of the earth at one time were once part of a single landmass. It is highly believed that all the continents have spread out due to plate tectonics.
FAQs on Longitudes
1. What are longitudes in geography?
Longitudes are imaginary vertical lines, also known as meridians, that run from the North Pole to the South Pole on the Earth's surface. They are used to measure the east-west position of a location. Along with latitudes, longitudes help in creating a coordinate system to pinpoint the exact location of any place on the globe.
2. How are longitudes measured?
Longitudes are measured in degrees (°), starting from the Prime Meridian, which is designated as 0° longitude. Locations are measured up to 180° to the east (East longitude) and up to 180° to the west (West longitude). The 180° East and 180° West meridians represent the same line, known as the International Date Line.
3. What is the importance of the Prime Meridian?
The Prime Meridian, at 0° longitude, is important for two main reasons:
- It serves as the universal starting point for measuring longitude, dividing the Earth into the Eastern and Western Hemispheres.
- It is the basis for the world's standard time zones. The time at the Prime Meridian is known as Greenwich Mean Time (GMT) or Coordinated Universal Time (UTC), which acts as a reference for all other time zones.
4. How many lines of longitude are there on Earth?
There are 360 degrees of longitude in total. This is typically represented by 360 imaginary lines or meridians. This includes the Prime Meridian (0°), 179 eastern meridians, 179 western meridians, and the 180° meridian (the International Date Line), which is a single line.
5. What is the main difference between latitude and longitude?
The main differences between latitude and longitude are:
- Direction and Shape: Longitudes are vertical semi-circles of equal length that run north-south and converge at the poles. Latitudes are horizontal, full circles of varying lengths that run east-west and are parallel to each other.
- Reference Line: The reference line for longitude is the Prime Meridian (0°). The reference line for latitude is the Equator (0°).
- Function: Longitude primarily helps determine time zones, while latitude is a key factor in determining climate zones.
6. How do longitudes help in determining time zones around the world?
Longitudes are fundamental to calculating time. The Earth completes a 360° rotation in 24 hours, meaning it rotates 15° of longitude every hour. This relationship is used to create the 24 standard time zones. Starting from the Prime Meridian (0°), for every 15° one moves eastward, the local time advances by one hour. Conversely, for every 15° one moves westward, the time moves back by one hour.
7. Why is the International Date Line (IDL) not a straight line?
The International Date Line, located at approximately 180° longitude, is not straight to avoid practical problems. If it were a straight line, it would pass through some countries and island nations, dividing them into two different calendar days. To prevent this administrative and social confusion, the line zigzags to keep politically and economically linked areas, like the islands of Kiribati, within the same day and date.
8. Why do all lines of longitude converge at the poles?
Lines of longitude, or meridians, converge at the poles by their very definition. They are defined as semi-circles that connect the North Pole to the South Pole. Since every meridian must start at one pole and end at the other, they naturally meet at these two points. This is unlike lines of latitude (parallels), which are defined as circles parallel to the Equator and therefore never intersect.
