Introduction to Geographical Information Systems

GGH 3703
INTRODUCTION TO GEOGRAPHICAL INFORMATION
SYSTEMS
ASSIGNMENT 6
LETTY POSH MABUNDZA
44006144

1

TABLE OF CONTENTS:
Assignment cover

page 1

Question 1

page 3-4

Question 2

page 4-6

Question 3

page 6-9

Question 4

page 10-14

Question 5

page 14-15

Question 6

page 15-16

Sources consulted

page 17-18

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QUESTION 1:
Given data:
 Mean annual temperature
 Average annual air pressure
 Boundaries of provinces
 Climate data
 Location of meteorogical stations
Spatial data:
 Boundaries of provinces
 Location of meteorogical stations
Attribute data:
 Mean annual temperature
 Average annual air pressure
 Climate data
 The raster data model uses a grid to cover the space and the value of each cell (pixel) in the grid to correspond to the characteristic of the geographic feature at the cell location. The cell is the smallest unit in the grid. A grid is a matrix of cells. Raster data is best used when your primary concern is with the locational relationships of the phenomena represented by geographic features and not the features themselves.
A vector data model is a representation of the world using points, lines, and polygons. Vector models are useful for storing data that has discrete boundaries, such as country borders, land parcels, and streets
 For mean annual temperature I will use a raster data module because the temperature of places have different values it is a continuous data because values can change at any time.
 For average annual air pressure I will use a raster data module because it is also a continuous data and the air pressure can change over a period of time and I will use lines to represent air pressure.  For the boundaries of the provinces I will use a vector data model, as it is a discrete boundary and I will use points to classify the layers.  For climate data I will use a raster data model, as values change from time to time, and values can be calculated.
 For the location of meteorogical stations I will use a vector