Chapter 1: The Earth as a Rotating Planet
The Shape of the Earth
- a perfect sphere?
- why or why not?
Earth Rotation
- what is it?
- how long does it take?
- if looking at Earth from above north pole, rotation is ______, while if looking at it from the equator, rotation is from ______to ______
- importance of rotation
1.
2.
3.
The Geographic Grid
- what is it?
- consists of imaginary lines
1. parallels – also called ______
o “run” in ______direction, but measure ______of reference
o how is the distance measured? (hint: what is the reference?)
o range:
o 1˚ of latitude = approximately 69 miles at Equator
o creates ______and ______hemispheres
o 5 well-known latitudes include:
2. meridians – also called ______
o “run” in ______direction, but measure ______of reference
o how is the distance measured? (hint: what is the reference?)
o range:
o distance between meridians varies, but is approx. = 69 miles x cosine (latitude)
o creates ______and ______hemispheres
o 2 well-known longitudes include:
o
- location of a point given as: latitude (degrees N or S), longitude (degrees W or E)
- two techniques: decimal degrees or degrees (˚), minutes (‘), seconds (“)
Map Projections
- Map:
- what problem arises from depicting a curved (3-D) object onto a flat (2-D) surface?
- types of distortion
1.
2.
3.
4.
5.
- some types of map projections:
1. polar
o circular, centered on N or S pole, meridians are straight lines, parallels are circles
o advantage:
o disadvantages:
2. Mercator (conformal projection)
o rectangular, meridians and parallels are straight lines
o advantages:
o disadvantages:
3. Goode (equal-area projection)
o odd shape, meridians both straight and curved lines, parallels are straight lines
o advantages:
o disadvantages:
Global Time
- Number of contiguous U.S. time zones?______
- solar noon:
- 15˚ of longitude = 1 hr (360˚ for one rotation of Earth / 24 hrs in a day = 15 degrees/hr)
- do time zones always follow this rule?
- International Date Line
o approximate location:
o why?
o Travel West and ______a day
o Travel East and ______a day
Earth’s Revolution
- what is it?
- direction if viewed from above:
- one complete revolution =
- responsible for:
- shape is ______, so Earth is closer to the Sun at certain times of the year
1. perihelion: Earth ______Sun; occurs in ______(N. Hemisphere winter)
2. aphelion: Earth ______Sun: occurs in ______(N. Hemisphere summer)
- equinoxes
o occur in ______(vernal) and ______(autumnal)
o subsolar point = ______
o hours of daylight
- solstices
o occur in: ______(summer) and ______(winter)
o subsolar point:
o 24 hrs of daylight