Section 1.2: Models of Earth
I.
Maps and Globes
A. Map: model on a flat surface of all or part of Earth’s surface as seen from above
B. Globe: sphere that represents Earth’s entire surface
i. Correctly shows the relative size and shape of landmasses and bodies of
water
ii. Scale: relates distance on a map to distance on Earth’s surface
iii. Symbols: pictures used by mapmakers to stand for features
a.) human-made features like highways and cities
b.) physical features like rivers, lakes, mtns
iv. Key: list of all symbols and their meanings
Compass Rose: North arrow; top of the map always North.
**Demo: Orange peel Discovery P 25..
How could you make a round object flat in the neatest way possible..?
Cut it like this!
II.
Maps and Technology
A. Timeline of mapmakers
i. From 1100’s to 1600’s, mapmaking used to benefit sailors
1. World travel and trade done solely by boat
2. Most maps in this time were to benefit sailors
ii. European voyages required maps that could show a spherical world on a flat map
1. Gerard Mercatur discovered how to “project” the image of the Earth onto a
piece of paper
= Mercatur projection
Imagine a candy wrapper around a piece of peppermint!
Read Pp 25-30
III.
An Earth Reference System (OPEN BOOK TO P.28-29)
A. The equator: imaginary line halfway b/t North and South Pole
i. Divides Earth into northern and southern hemispheres
ii. Hemisphere: one half of the Earth
Ex. “Hemi” = half
Ex. Ecuador is the Spanish word for equator, where do you think it is located
(show on globe)
B. The Prime Meridian: imaginary line that runs from North pole to South pole.
i. Passes through Greenwich, England
ii. Divides Earth into Eastern and Western Hemispheres
C. Measurements on a Sphere
i. Degree; the units used by scientists to measure distances around a circle
1. One degree = 1/360th of the way around a complete circle
IV.
Locating points on Earth’s Surface
A. Latitude: imaginary lines parallel to the equator
i. The equator is the starting point for measuring latitude
ii. Equator= 0 degrees
iii. Latitude of each pole is either 90 degrees north or south
B. Longitude: distance in degrees east or west of the Prime Meridian
i. There are 360 degrees of longitude, running north and south and meeting at
the poles
ii. If each line of longitude = one degree, how many lines of longitude are
there?? 360
iii. Prime meridian= 0 degrees; The degrees run to 180 degrees east and west
1. 180 east = 180 west
C. Map projections: framework of lines that helps to show landmasses on a flat
surface
1. Mercatur projection: all latitude and longitude lines appear straight
and parallel
a.) Landmasses near the poles are severely distorted
2. Equal-area projections: more accurately shows landmasses in relation
to one another and to Earth