 Cartography – science of mapmaking

 Equator circles Earth halfway between the north and south poles ◦ Separates Earth into 2 equal halves (hemispheres)

 Latitude – distance North or South of equator ◦ Parallel ◦ Measured from 0 ° at equator and 90 ° at poles

 Each degree of latitude is 111km on Earth  Can be broken into 60 smaller units called minutes (‘)  Minutes can be broken into seconds (“)

 Longitude - distance in degrees east or west of the prime meridian. ◦ Prime meridian (Greenwich meridian) – 0 ° longitude ◦ Large semi-circles that extend vertically from poles ◦ Not parallel

 West of the prime meridian are numbered from 0° to 180° W  East of the prime meridian are numbered from 0° to 180° E

 Both latitude and longitude are needed to locate a coordinate  LATITUDE ALWAYS COMES FIRST!!!!

 Locating coordinates on a map.

 Earth is divided into 24 times zones  Each time zone is approx. 15 ° Why are some of the time zone boundaries irregularly shaped?

 There are 6 time zones in the US

 International Date Line – 180 meridian ◦ West across IDL – you advance 1 calendar day (lose a day) ◦ East – move back 1 day (gain a day)

 Calculating time in other time zones

 Maps are flat models of the 3D Earth  Projection – transferring points and lines on a globe’s surface to sheet of paper

 Mercator projection ◦ Parallel lines of latitude and longitude  Conic projection ◦ Projecting points from a globe onto a cone  Gnomonic projection ◦ Projecting points from a globe onto a piece of paper that touch the globe at a single point

 Topographic maps show elevations of hills and valleys of an area. use lines, symbols, and colors to represent changes in elevation

 3 Dimensional Maps ◦ Used to visualize earth 3 dimensionally to show rivers, mountains, valleys, and hills

Contour Lines –Contour line connects points of equal elevation. –Elevation - distance of a location above or below sea level. Contour lines that are closer together indicate a steep slope

–Contour interval - difference in elevation between two side-by-side contour lines –Depends on the terrain –Index Contours – contour lines labeled with a number What is the contour interval on this map? Contour Interval = 20, which means each line represents a change of 20 units Index Contour

What is the contour interval? Contour Interval = 20

–Depression contour lines - represent features that are lower than the surrounding area –Have hachures –short angled lines that point toward lower elevation

Map legend explains what the symbols represent.  Maps include both human- made and natural features that are located on Earth’s surface

Map scale - ratio between distances on a map and actual distances on the surface of Earth Graphic Verbal Representative fraction

 Topographic Mapping