A model or representation of the Earth’s surface

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A model or representation of the Earth’s surface
Map Reference point Cardinal directions Latitude equator A model or representation of the Earth’s surface Is a fixed point on the Earth’s surface from which direction and location can be described Example: a landmark like the north or south pole (because the Earth is round) North, south, east and west More precise than left, right, and straight True north: the geographic north pole – it never changes, unlike the magnetic north pole Imaginary lines drawn around the Earth parallel to the equator Called parallels The distance north or south from the equator measured in degrees A circle ½ between the poles that divides the Earth between Northern and Southern Hemispheres 0° latitude

Using Latitude and Longitude
Prime Meridian Using Latitude and Longitude Imaginary lines that pass through the poles Called meridians The distance east or west from the prime meridian measured in degrees Not parallel, touch at the pole and farthest apart at the equator The meridian selected to be 0° longitude Greenwich, England Does not completely circle the globe 180° is the opposite side Eastern Hemisphere is between 0°-180° - east of Prime Meridian Western Hemisphere is between 0°-180° - west of Prime Meridian Find the intersecting points on the map The points make a grid, connect north & south with east & west points

Losing accuracy Mercator Projection Conic Projection
Because the Earth is a sphere, accuracy is lost when information is transferred Distortions in shape and distance A map projection where the contents of the globe are transferred onto a cylinder of paper. Latitude and longitude lines are straight & parallel Widens the area near the poles A map projection made by transferring the contents of the globe onto a cone and unrolled Touches each line of longitude, but only one line of latitude Distortion occurs along the lines of latitude further away from the one touching the cone Best for East/West landmasses

A map projection made transferring the globe onto one plane
Azimuthal Projection Modern Map Making Information on Maps A map projection made transferring the globe onto one plane Only touches one point, usually a pole Little distortion at that point Distortion occurs from that point on Aerial Photographs – give a bird’s-eye view Remote sensing – gathering information without actually being there (satellites) The keys to what is on any given map Title – telling you what type of map it is Scale – Earth surface vs. map surface Graphic scale – comparison ruler Verbal scale – describes the scale Representative fraction – ratio Compass rose – shows North Legend – shows symbols (key) Date – when the map was accurate