Topographic Topographic Maps and Maps and Satellite Satellite ViewsViewsViewsViews

TEKS 8.9C interpret topographic TEKS 8.9C interpret topographic maps and satellite views to maps and satellite views to identify land and erosional identify land and erosional

features and predict how these features and predict how these features may be reshaped by features may be reshaped by

weathering.weathering.weathering.weathering.

Cartographers Cartographers

(map makers) (map makers)

use data from use data from

aerial photos aerial photos

and remote and remote and remote and remote

sensing to sensing to

create maps of create maps of

landforms. landforms.

SatellitesSatellitesorbiting the orbiting the

Earth Earth photograph photograph the surface to the surface to provide views provide views provide views provide views of the Earth of the Earth we normally we normally would not be would not be

able to see.able to see.

The photos from The photos from satellites correlate to satellites correlate to maps that show themaps that show the

shapeshape andand elevation elevation of a of a

given area.given area.given area.given area.

These are These are called called

topographic topographic maps.maps.maps.maps.

Topographic maps are Topographic maps are useful because they model useful because they model the the threethree--dimensional land dimensional land using lines and symbols.using lines and symbols.

Topographic maps Topographic maps show the location and show the location and shape of landforms shape of landforms

using using contour linescontour lines..

Contour lines are Contour lines are imaginary lines that imaginary lines that connect points with connect points with connect points with connect points with the same the same elevationelevation..

Each contour line Each contour line represents one represents one

elevationelevation..

Contour lines never cross.

Differences in Differences in elevation are elevation are shown with the shown with the

spacingspacingbetween between between between

contour lines. contour lines. This is called This is called the the contour contour intervalinterval..

CloselyClosely spaced spaced contours represent contours represent

steep slopes.steep slopes.

WidelyWidely spaced spaced contour lines contour lines

represent gentle represent gentle slopes.slopes.

When contour lines When contour lines cross a cross a stream or stream or riverriver, the lines are , the lines are bent to form a “V” bent to form a “V”

shape.shape.shape.shape.

uphill

downhill

Direction of water flow

The “V” The “V” points points uphilluphill

or or upstream. upstream. So the tip of So the tip of the “V” the “V” the “V” the “V” points points

oppositeopposite the the direction the direction the stream or stream or river is river is

flowingflowing..