Maps, Scale & Locating Places in Ghana

A map is a scaled, flat representation of the Earth's surface or a portion of it, showing physical, political, or socio-economic features as viewed from directly above (birds-eye view). • Major Types of Maps: 1. Physical (Topographical) Maps: Show natural landforms and water bodies—mountains, plateaus, valleys, rivers, and coastal wetlands using contour lines and color gradients (green for lowlands, brown for highlands, blue for water). 2. Political Maps: Show human-made administrative boundaries, regional borders, sovereign nations, and capital cities (e.g. Map of Ghana showing its 16 administrative regions and regional capitals). 3. Thematic (Special Purpose) Maps: Focus on a specific subject or distribution pattern (e.g. Annual Rainfall Map of Ghana, Mineral Distribution Map, Population Density Map).

A drawing is not a valid map unless it includes the essential cartographic components: 1. Title: Stated clearly at the top, telling what the map portrays, its location, and subject (e.g. "Map of Ghana Showing Major Mineral Deposits"). 2. Orientation / Compass Rose: An arrow pointing to Cardinal North (N), helping the reader determine direction (North, South, East, West). 3. Scale: Shows the mathematical relationship between a measured distance on the map and the actual corresponding distance on the ground. 4. Legend / Key: An explanatory box defining all cartographic symbols, shading, and colors (e.g. blue lines for rivers, black squares for towns, crossed hammers for mines). 5. Border (Margin): A neat enclosing frame around the map that defines its geographic boundaries. 6. Date & Author: When the survey was executed and the cartographer or agency responsible (e.g. Survey and Mapping Division of Ghana).

A scale is the ratio between distance on paper and ground distance in reality: • 1. Statement Scale: Expressed in direct words. - Example: "1 centimeter represents 2 kilometers" (means 1 cm on the map equals 2 km on the ground). • 2. Linear (Graphic) Scale: A divided horizontal line or bar marked in units of kilometers or miles. - Divided into Primary divisions (to the right of zero, showing whole units) and Secondary divisions (to the left of zero, divided into finer fractions like meters). - Advantage: If the map is enlarged or photocopied, the linear scale resizes proportionally, remaining accurate! • 3. Representative Fraction (RF) Scale: Expressed as a pure ratio or fraction without physical measurement units. - Example: 1:50,000 (means 1 unit on map represents 50,000 of the same units on the ground). - 1 cm on map = 50,000 cm on ground (= 500 meters or 0.5 km).

• Calculating Ground Distance from a Statement Scale: Formula: Actual Distance = Map Distance (measured with a ruler) × Scale Factor. Worked Example: - Distance measured on map between Kumasi and Sunyani = 8 cm. - Map scale: 1 cm represents 15 km. - Ground Distance = 8 cm × 15 km = 120 km. • Converting RF to Statement Scale in Kilometers: Metric conversion rule: 100 cm = 1 meter; 1,000 meters = 1 kilometer; therefore, 100,000 cm = 1 km. - Example: Convert 1:200,000 to a statement scale. - Step: Divide 200,000 cm by 100,000. - 200,000 ÷ 100,000 = 2 km. - Statement scale: "1 cm represents 2 km". • Measuring Curved Distances (Winding Rivers or Roads): Use a piece of thread or the edge of a strip of straight paper to trace along the curves carefully, then measure the straight thread against the ruler or linear scale.