Chapter 3 Notes
Section 1-3
While You Read
1. Mercator Projection
Strengths: shows whole world on one
map, shows true directions as straight
lines;
Weaknesses: distorts areas near
poles
Latitude Lines |
Longitude Lines |
2. Gnomonic Projection:
Strengths: accurately shows shortest
distance between two points; shows
polar regions well;
Weaknesses: distorts land mass shapes
away from center; shows only part of
the Earth
Gnomonic
Gnomonic
Stereographic
Orthographic
3. Polyconic Projection
Strengths: landforms have true size
and shape relation to each other;
shows middle latitudes well.
Weaknesses: distorts areas at poles;
shows only part of Earth
Polyconic
4. Globe
Strengths: most accurate
representation of our threedimensional planet;
Weaknesses: difficult to transport
After You Read
Explain the importance of map scales and
orientation.
Map scales allow you to determine real
distances and relationships of the
features on the map.
Orientation tells you direction, without
which you cannot relate a map to the
real places it depicts.
3.2 Mapmaking and
Technology
While You Read
1. Plane-table surveying: draw map from
highest point, using sighting device
and visual observation.
2. Photos from airplanes: draw map by
copying contours of land from aerial
photos.
3.2 While You Read
3. Radar: use radio signals to create
images regardless of weather.
4. Satellite imaging: use sensors to make
images from light waves
5. GPS: combine computer and satellite
technology to locate people or places
anywhere on Earth
3.2 After You Read
Explain how weather might affect the
mapmaking technologies discussed in
this lesson.
Weather could cause visibility problems
for plane-table surveys and airplane
photography. Weather has little effect
on satellite and GPS technologies
3.3 Topographic Maps
After You Read
1. Topographic map: map that shows the
altitude of land
2. Uses: city planning, road engineering,
resource search, outdoor recreation
3. Symbols: color and shape indicate natural
and human-made features
4. Contour lines: connect points of the same
elevation
5. Slope: distance between contour lines
shows slope of the land.
Additional Questions
1. What device detects and records data
from Earth’s surface?
2. In what form does the data travel?
3. What happens to the data once it is
recorded?
Additional Questions
4. What does GIS and GPS stand for?
5. What are some uses for GPS?
6. Why would a hiker find topographic
maps useful?
Answers
1. A scanner on a satellite.
2. As electromagnetic waves
3. Computers convert the data to code,
then to pixels, and finally to usable
images.
Answers
4. GPS – Global Positioning System
GIS – Global Information Systems
5. Locate people and vehicles when they
are lost, help someone find a route to a
destination, and investigate scientific
phenomena such as ocean currents, or
help law enforcement create a database
of deer/car collisions.
Answers
6. Hikers can use topographic maps to
find their way relative to land features,
avoid bodies of water and too-steep
trails, and estimate how far they have to
travel.