1. Lesson One - Four

2. Latitude lines are imaginary lines on the earths surface. They run east and west around the globe and tell you your distance north or south of the Equator. 3. Think of latitude like the rungs of a ladder (laddersounds a lot like latitude). Latitude lines run eastand west, but they tell how far up (north) you can goor how far down (south) you can go. 4. Longitude lines are imaginary lines on the earths surface that run from pole to pole around the globe and tell you your distance east or west from the Prime Meridian. The red line shows a longitude line. 5. When you think of longitude, think of long, talltelephone poles (because longitude lines run frompole to pole). Longitude lines run north andsouth, but they tell how far east you can go or howfar west you can go. 6. Inthe field of mathematics, circles are measured in degrees. There are 360 degrees in a circle. Since the earth is basically circular, it was decided to measure latitude and longitude in degrees also. 7. The first latitude line was the Equator (equally distantbetween the north and south poles). It is the largestof all latitude lines. All other latitude lines aremeasured in degrees north or south of the Equator.There are a maximum of 90 degrees of latitude to thenorth or the south of the Equator. 8. The first longitude line was thePrime Meridian. Any meridian couldhave been chosen as the PrimeMeridian because they are all exactlythe same. The Prime Meridian wasselected by international agreementat the International MeridianConference called by PresidentChester Arthur in October of 1884.Representatives from 25 nations metin Washington, D.C. All otherlongitude lines are measured indegrees east or west of the PrimeMeridian. There are a maximum of180 degrees on longitude to the eastor the west of the Prime Meridian. 9. It is approximately 70 milesbetween two latitude lines. Formore accuracy inlocation, degrees can bedivided into smaller parts. Onedegree can be divided into 60minutes () and one minute canbe divided into 60 seconds (").We will not use minutes orseconds of latitude andlongitude in this course. 10. If someone asked youthe location of the localtown bank, you may say"It is on the corner ofMain and Third streets."Latitude and longitudeare like imaginarystreets on the earth. 11. Itis customary to give the latitude of aplace first, and the longitude second.For example, you would say "35 degreesnorth, 77 degrees west". This eliminatesthe need to say the words latitude andlongitude. Make sure that you give a direction withthe number. If you simply say "66 degreeslatitude", there are two of them - one in thenorth and one in the south. 12. 1. Go to your starting line (the Equator).2. Determine which direction you must go (north or south).3. Determine the distance in degrees you must go (60). 13. 1. Go to your starting line (the Prime Meridian).2. Determine whichdirection you mustgo (east or west).3. Determine thedistance in degreesyou must go (40). 14. If you find theintersectionof these twoimaginarystreets, youhave foundthe exact(absolute)location of aparticularplace on theearthssurface(shown by thered "X" on themap below. 15. Useyour skill builder sheet and the mapon the next slide. For each question: Select which letter matches the correct latitudeand longitude coordinates on the map. Record the letter on your Skill Builder sheet. You may go back to previous slides for a reminderof latitude and longitude. 16. In real life, there are severalinstances where you wouldneed to know how to findlatitude and longitude. For example, when weatherforecasters are trackinghurricanes, they note theabsolute location on aperiodic basis to see the pathof the storm and try to predictthe future path based partiallyon these findings. 17. Inthe military. Suppose you were at war and you wanted to blow up an ammunition factory, but not the hospital nearby. Using minutes and seconds of latitude and longitude, you can launch a missile from hundreds of miles away and strike only that particular building. 18. Ifyou wanted to license a CB basestation, or even license 5-mile rangewalkie talkies, you need to provide thelatitude and longitude of your home to theFederal Communications Commission toget such a license. 19. Inan emergency situation, like a plane crash or a ship sinking, you can relay your coordinates of latitude and longitude to assist rescue teams when time may be very important. If you are in the middle of an ocean, there are no landmarks to use, so you had better know your latitude and longitude. 20. Explore at least two more sites and find two facts you havent learned yet about latitude and longitude. Record them on your skill builder worksheet. http://geographyworldonline.com/tutorial/fu rther.html