Question

review questions

1. how was john snows \ghost map\ an application of gis principles?
2. explain why a map is simply a model of part of the earths surface.
3. discuss the differences between large - scale and small - scale maps.
4. how are map grid lines like landmarks? how are they different?
5. which grid lines on a standard map are the vertical lines? which are the horizontal lines?
6. before modern navigation methods, such as gps, how did sailors find their longitude?
7. list three features on a standard map that help you use it better.
8. why is a map projection needed?
9. what are the advantages of plane, cylindrical, and conic projection surfaces in cartography?
10. what kind of projection would show the continent of antarctica with the least amount of distortion?
11. what are three types of standard maps? which would likely show glaciers and lakes?
12. why are thematic maps useful?
13. name the three main parts of a geographic information system (gis).
14. give an example of an earth feature that could be represented by each of the gis data types.
15. what is the most efficient way to collect gis data over large areas?

Explanation:

1. John Snow's "Ghost Map" plotted cholera cases on a map, using spatial - analysis which are GIS - like principles.
2. A map is a model as it represents a real - world area in a simplified way.
3. Large - scale maps show more detail of a small area; small - scale maps show a large area with less detail.
4. Map grid lines are like landmarks as they help in location, but landmarks are real - world features while grid lines are on the map.
5. On a standard map, vertical lines are meridians (longitude) and horizontal lines are parallels (latitude).
6. Before GPS, sailors used celestial navigation methods like observing the position of the sun and stars to find longitude.
7. Features like scale, legend, and compass rose help in using a map better.
8. Map projection is needed to represent the curved surface of the Earth on a flat surface.
9. Plane projection is good for small areas, cylindrical projection preserves shape well in some cases, and conic projection is useful for mid - latitude regions.
10. A polar projection would show Antarctica with the least distortion.
11. Three types of standard maps are topographic, political, and physical. Physical maps would likely show glaciers and lakes.
12. Thematic maps are useful as they show specific themes like population density or land use.
13. The three main parts of a GIS are data, software, and hardware.
14. Point data could represent a mountain peak, line data a river, and polygon data a forest area.
15. Remote sensing using satellites or aircraft is the most efficient way to collect GIS data over large areas.

Answer:

1. John Snow plotted cholera cases spatially, similar to GIS principles.
2. It's a simplified representation of a real - world area.
3. Large - scale: more detail of small area; small - scale: less detail of large area.
4. They help in location like landmarks, but grid lines are on - map features.
5. Vertical: meridians; Horizontal: parallels.
6. Using celestial navigation methods.
7. Scale, legend, compass rose.
8. To represent the Earth's curved surface on a flat surface.
9. Plane: good for small areas; Cylindrical: preserves shape; Conic: for mid - latitudes.
10. Polar projection.
11. Topographic, political, physical. Physical maps.
12. They show specific themes.
13. Data, software, hardware.
14. Point: mountain peak; Line: river; Polygon: forest area.
15. Remote sensing.