3 HemispheresHemispheres are used to divide the earth into quadrants (quarters), using the cardinal points as a reference.Northern HemisphereSouthern HemisphereEastern HemisphereWestern HemisphereBut where do we place the lines that distinguish one hemisphere from another?
4 Latitude and Longitude Latitude and Longitude Acts as a grid system for the entire earthLatitude: There are 90 degrees of latitude in two directions, both North and South. They are known as parallels, and their starting point is at the equator.Longitude: There are 180 degrees of longitude in two directions, East and West. They are known as meridians, and their starting point is the Prime Meridian.
5 Important Imaginary Lines Equator: the line that runs horizontally along the center of the earth. It is equally distant from each of the poles. (0 degrees N and S)
6 The Tropics: Cancer and Capricorn Tropic of Cancer: horizontal line at 23.5 degrees north of the equator. It is the northern limit of direct sunlight.Tropic of Capricorn: horizontal line at 23.5 degrees south of the equator. It is the southern limit of direct sunlight.Tropic of CancerTropic of Capricorn
7 The Circles: Arctic and Antarctic The Arctic Circle: Horizontal line at 66.5 degrees north of the equator.The Antarctic Circle: Horizontal line at 66.5 degrees south of the equator.*Each receive no sunlight at opposite times during the year.
8 The Prime MeridianPrime Meridian: A vertical line that extends from one pole to the other (signifies 0 degrees of longitude). It passes through Royal Observatory at Greenwich, England (part of London).It also passes through France, Spain, Burkina Faso, Mali, Togo, and Ghana.
9 International Date Line International Date Line: A vertical line that runs from one pole to the other. It is exactly opposite to the Prime Meridian, and is considered 180 degrees, East and West.This line passes through the pacific ocean.
11 PracticeWhen determining a location using latitude and longitude, Latitude (the horizontal lines) is listed first. It must have a direction (N or S)“D” is located at:60 degrees South, and 40 degrees West.
12 Practice Find the Latitude and Longitude of E and A. E: 40 degrees North, 60 degrees East (40N 60E)A: 20 degrees South, 100 degrees East (20 S 100 E)
13 Minutes and Seconds For precision purposes, degrees of longitude and latitude have been divided into minutes (') and seconds ("). There are 60 minutes in each degree. Each minute is divided into 60 seconds. Seconds can be further divided into tenths, hundredths, or even thousandths. e.g. Galveston Island, Texas, USA, is located at 29 degrees, 16 minutes, and 22 seconds north of the equator, and 94 degrees, 49 minutes and 46 seconds west of the Prime Meridian.
14 Distance between Lines If you divide the circumference of the earth ( kms) by 360 degrees, the distance on the earth's surface for each one degree of latitude or longitude is approximately 110 km.Note: As you move north or south of the equator, the distance between the lines of longitude gets shorter until they actually meet at the poles.
15 To the TEXT!!!Complete the Atlas exercise on p.36 of your textbook.