SUBJECT: GEOGRAPHY
CLASS: SS1
DATE:
TERM: 1ST TERM
REFERENCE MATERIAL
- Essential Geography for Senior Secondary Schools, O.A. Iwena.
WEEK FOUR
TOPIC: LATITUDE AND LONGITUDE
MEANING OF LATITUDE
Latitude is an angular distance of a point on earth’s surface measured in degrees from the centre of the earth. Latitude is parallel to the equator .Equator divides the earth into two equal halves known as Northern & southern hemisphere. Lines of latitude are sometimes called parallel of latitude.
IMPORTANT LINES OF LATITUDE
- The equator 0° (ii) North pole 90°N (iii) South pole 90°S (iv) The tropic of Cancer 23 1/2°N (v) Tropic of Capricorn 23 1/2°S (vi) Arctic circle 66 1/2°N (vii) Antarctic circle 66 1/2°S .
USES OF LINES OF LATITUDES
- The lines of latitude are used to determine the exact location of a place on the atlas map.
- They are used to calculate the distance between two places on the earth surface.
LONGITUDE
Longitude is an angular distance measured in degree east and west of the Greenwich Meridian. It is an imaginary line drawn on the globe (earth) running from north to south at right angle to the parallels.
The longitude passing through London and Accra is called the Great, Prime or Greenwich meridian and it is on longitude 0°. All longitudes are called meridian.
IMPORTANT LINES OF LONGITUDE
Long 0° (Prime Meridian) , long 45°E , long 45°W long 90°E long 90°W long180°E etc.
USES OF LINES OF LONGITUDE
- They are used to calculate local time.
- They are used to determine the exact location of places on the atlas map.
Similarities between Lines of Latitudes and Meridians
- Both are used for location of places on the map.
- Both are numbered in degrees.
- Both are imaginary lines drawn on the globe.
- Both contain great circles.
EVALUATION QUESTIONS
- What is latitude?
- Mention the important lines of latitude and longitude
Differences between Lines of Longitude and Lines of Latitudes
Lines of latitudes Lines of longitudes
- Equator is the only great circle It has many great circles as opposite parts of
lines make a great circle.
- Lines are shorter towards the pole Lines are of the same length.
- They run from West to East They run from North to South.
- Lines are parallel to each other Lines are not parallel to each other but converge at
the poles.
- The lines are called parallels The lines are called meridians.
- Lines are used for measuring Lines are used for calculating local time.
distance
- Has the equator as its reference Has Greenwich meridian as its reference
point point.
- Latitude measures up to 180° i.e Longitudes measures up to 360° i.e
90°N - 90°S 180°W - 180°E.
GREAT CIRCLE AND SMALL CIRCLE
A great circle is any line that divides the earth into two equal halves or hemispheres. The centre of the great circle is also the centre of the earth.
Two opposite lines of longitude make a great circle e.g long 0°, 180°W and 180°E, long.300W and long15°W, long110°W and 70°E, etc .
On the other hand, a small circle is any line that does not divide the earth into two equal halves or hemisphere. All lines of latitude are small circles except the Equator. Examples are lat.90°N, 90°S, Tropic of cancer, Tropic of Capricorn etc.
EVALUATION QUESTIONS
- Differentiate between lines of latitude and lines of longitude.
- Describe a great circle.
GENERAL EVALUATION
- Mention two uses of lines of latitude and longitude.
- State two similarities and four differences between longitude and latitude.
- Describe a small circle.
- What is a great circle?
READING ASSIGNMENT
Essential Geography, O.A. Iwena, Pages 14-17.
WEEKEND ASSIGNMENT
- 1. Lines of longitude can best be described as (a) The angular distance of a place north or south of the equator (b) semi circle on the globe (c) imaginary lines on the earth’s surface joining the north and south poles
- The angular distance of a point on the earth’s surface measured in degrees from the centre of the earth is known as (a) latitude (b) longitude (c) international date line
- The shortest flying route between any two points on the earth surface lies along the (a) Tropic of Capricorn (b) Tropic of Cancer (c) Great circle
- A great circle can be described as (a) a line of longitude (b) the line of latitude (c) a shortest distance between two points on the globe
- The following are the similarities between lines of longitude and latitude except (a) both are used to calculate local time of a place (b) both are numbered in degree (c) both contain great circles
THEORY
- State two differences between longitude and latitude.
- List five important lines of latitude.