What is a precis map?

What is a precis map?

A precis map is a simple summary map which shows only the main features of a topographical map. A precis map represents the locations of different categories of information.

What is an example of a map?

Political maps, physical maps, road maps, topographic maps, time zone maps, geologic maps, and zip code maps are all examples of reference maps. A variety of reference maps have been created for almost every country of the world. Thematic maps show the variation of a topic (the theme) across a geographic area.

Why are Precis maps useful?

A précis map represents the locations of different categories of information, for example vegetation type. Create a précis map showing the major vegetation types in the area.

What is an Isoline on a map?

An isoline map is a way of presenting numerical data cartographically, helping readers to recognize geographical patterns and relationships. Isolines are lines drawn on maps connecting data points of the same value.

What’s an example of an Isoline?

A line of constant value on a map or chart. Examples include isobar (equal barometric pressure), isotherm (equal temperature), and isohyet (equal precipitation).

How do I read an isopleth map?

The third dimension is shown by a series of lines called isopleths which connect points of equal value. The isopleth interval is the difference in value between two adjacent isopleths. Note, the values of the isopleths drawn on the map are ALWAYS multiples of the interval.

Why can’t Isolines never cross?

Contour lines never cross on a topographic map because each line represents the same elevation level of the land.

Do Isolines ever end?

Isolines never end, except at the edge of a map. The change in value from one isoline to the next is always the same.

Why can contour lines never touch?

Contour lines don’t cross because each line represents a particular elevation. If two contour lines crossed, the place where they intersect would have two different elevations, and this simply isn’t possible.

How do the lines indicate which side of the mountain is the steepest?

Contour lines that are close together indicate a steep slope, where the elevation changes quickly over a short distance. If the contour lines are so close together that they seem to touch, they indicate a very steep slope, such as a cliff. In contrast, contour lines that are far apart indicate a gentle slope.

What does a gentle slope look like?

Gentle: Contour lines showing a uniform, gentle slope will be evenly spaced and wide apart. Easy walking. Steep: Contour lines showing a uniform, steep slope on a map will be evenly spaced, but close together.

What is considered a gentle slope?

The slope distance is 100.2 ft. for a run of 100 ft. As you can see from this example, in a forest, a six percent slope would be considered a gentle slope. For example, a 25 percent slope is simply a ratio of 25:100.

Which side slope is the most gentle?

If you are using a topographic map, the most gentle slope will be where the lines are furthest apart.

How can you identify a steep area on a topographic map?

Interpreting Contour Maps

1. Closely-spaced contour lines indicate a steep slope, because the elevation changes quickly in a small area.
2. Contour lines that seem to touch indicate a very steep rise, like a cliff or canyon wall.
3. Broadly spaced contour lines indicate a shallow slope.

How do you describe a topographic map?

Topographic maps are a detailed record of a land area, giving geographic positions and elevations for both natural and man-made features. They show the shape of the land the mountains, valleys, and plains by means of brown contour lines (lines of equal elevation above sea level).

What does a valley look like on a topographic map?

Valleys are elongated low-lying depressions usually with a river flowing through it. You know that you’re looking at a valley bottom when contour lines are V or U-shaped. All rivers flow downhill from higher to the lower elevations, perpendicular to the contour line above it.