2. Objectives 3-4
3- Differentiate between Mercator, Robinson and Conic map projections.
4- Calculate time and date in different time zones

3. Map Projections
Projections
Image of the Earth projected on paper

4. Map Projections: Mercator
Lat. & long. lines parallel
Covers large area (global)
Distortion at the poles

5. Map Projections: Robinson
Accurate continental shapes
Lines of lat. are parallel
Lines of long. are curved
Less distortion near poles

6. Map Projections: Conic
Accurate for certain latitudes
Distortion at poles and equator
Usually covers a small area

7. Why Time Zones?
video

8. Why do we have time zones?
Earth rotates once every 24 hours
West to east

9. Why do we have time zones?
Divide earth into 24 time zones (25)
Each unit is 15o wide
= 1hr time change
Eastward advance hour
Westward subtract hour

10. Rules for Changing Date
Date changes when crossing International Date Line
Cross westward = advance a day
Cross eastward = go back a day
Day must change at midnight