Chapter One: True Maps, False Impressions

Study Notes

Map Basics:

• Map Scale – Map scale refers to the degree to which a map “zooms in” on an area. It can be defined as the ratio of map distance (distance between two points on a map) to earth distance (distance between those two points on the surface of the earth), measured in the same units. Large scale maps depict small areas; small scale maps depict large areas.
• Map projection – Map projection is a systematic method of transferring the spherical surface of the earth to a flat map. It is impossible to represent a 3-D sphere on a flat 2-D piece of paper without stretching or compressing it in some way, so every projection is therefore distorted.
• Mercator projection - A Mercator projection is a type of map in which the true compass directions are kept intact (lines of latitude and longitude intersect at right angles), but areas are distorted (for example, polar areas look much larger than they really are). Mercator Projections are useful for nautical navigation. Usually a cylindrical shape.
• Time zones - Time zones are areas of the Earth that have adopted the same standard time, usually referred to as the local time. Every 15 degrees has a time zone. For every time zone you travel east, you add on an hour. For every time zone west, you take away an hour.
• Date Line - The International Date Line (IDL), also known as just the Date Line, is an imaginary line on the surface of the Earth opposite the Prime Meridian which offsets the date as one travels east or west across it. The International Date Line is the imaginary line on the Earth that separates two consecutive calendar days. That is the date in the Eastern hemisphere, to the left of the line, is always one day ahead of the date in the Western hemisphere. It has been recognized as a matter of convenience and has no force in international law. It is located 180 degrees away from Prime Meridian.
• Prime Meridian - A meridian of longitude 0 degrees that runs through Greenwich, England, and is used as the origin for measurements of longitude.
• 23.5 degrees axial tilt - The fact that the Earth is on a 23.5 degree tilt causes seasons. The Earth's axis is tilted 23.5^o from the vertical. This means that solar energy strikes the Earth's surface unevenly. It is summer in the Northern Hemisphere when the North Pole tilts toward the Sun. This puts the Sun more overhead, so solar energy strikes the Earth most directly. Simultaneously, the Southern Hemisphere is experiencing winter, because the Sun's rays are least directly overhead. In half of a revolution (6 months), the North Pole tilts away from the Sun, making solar energy least direct, so it is winter in the Northern Hemisphere, and summer in the Southern Hemisphere. Fall and spring occur in between these two extremes when the axis is tilted neither toward nor away from the Sun.
• Tropic of Cancer - The most northern point on the earth where the sun is directly overhead, located at approximately 23.5 degrees North latitude.
• Tropic of Capricorn - The most southern point on the earth where the sun is directly overhead, located at approximately 23.5 degrees South latitude.

Five Themes of Geography:

• Location – The absolute position of something on the surface of the earth and its relative proximity to other related things
• Place – The local human and physical characteristics that uniquely define a place and give it meaning to its inhabitants
• Region – An area characterized by similarity or by cohesiveness that sets it apart from other areas
• Movement – The flow of people, goods, money, ideas or materials between locations near or far
• Human / Environmental Interaction – The ways in which human society and the natural environment affect each other

Types of Maps and Distortion of Truth:

• General purpose map – reference or place maps
• Thematic map – thematic maps present a certain theme or set of information to a viewer
• Qualitative map – show specific points of information that does not include numbers (i.e. language)
• Quantitative map - show specific points of information that includes numbers (i.e. population)
• Dot maps – use dots to point out certain areas of interest
• Graduated circle maps – a series of graduated circles show an increase in whatever is being explored
• Isometric maps – isolines isolate areas that share a certain quality, such as contours or elevation
• Isoline – isolate areas on isometric maps that share a certain quality
• Contour line – A contour line separates areas of differing number value on a contour line map
• Isopleth – isopleth maps use colour to indicate certain areas that have the same characteristic. Defined and coloured by value, not artificial boundaries 
• Choropleth – use colour, but are defined by artificial boundaries (i.e. provinces)
• Cartogram – a diagram which uses the form of a map to present numeric information while maintaining some degree of geographic accuracy
• Mental map – your mind’s eye view of the world