Cartography: Map-Making & Visual Communication

Cartography Basics

• Cartography is part of geography and focuses on map-making, not just writing but visual communication.
• Maps communicate information to the reader and are always partial.
• Maps have inherent ideologies influenced by the author's choices (scale, projections etc).
• Understanding maps requires adhering to cartographic rules and standardization.
• Essential map elements: title, scale, legend, orientation.
• A title is critical for any map to inform the reader of the map's subject.
• Scale shows how much the real world is reduced to fit the map.
• Legends explain any non-standard symbols in the map.
• Orientation (like a north arrow) is necessary even if the map is not conventional (south-up).
• Maps can be misunderstood if the info is too complex or the conventions are ignored.
• Good maps typically have a maximum of seven legends for clarity.
• Anamorphosis distorts areas relative to a phenomenon's intensity.
• Anamorphosis isn't a map, but a cartographic technique.
• Example: a map showing carbon emissions might make the US larger and Cuba smaller.

Remote Sensing

• Maps are typically based on capturing images via remote sensing technologies.
• Remote sensing captures map images and can be done via aerophotogrammetry or satellite imagery.
• Aerophotogrammetry involves taking aerial photographs from aircraft.
• Aerophotogrammetry is suited to smaller areas like municipalities.
• Satellite imagery is commonly used to create maps of varying scales.
• Satellite imagery enables detailed maps from street-level to global views in programs like Google Earth.
• Civilian satellite imagery is less advanced than military-grade technology.
• Civilian satellite imagery is ~25 years behind military tech.
• Satellite imagery is used for weather forecasting, urban planning, and agriculture.
• Ethical concerns: satellite imagery can be used for surveillance.

Map Scales

• Map scales in geography are always reductive, showing how much the real world is scaled down.
• Scales are a key concept, indicating reduction, but other scales like the engineering field can increase the view of an object.
• Two types of scales: graphic/bar scales and numerical scales
• Graphic scales use a line divided into segments to show distances.
• Graphic scale- measure with a ruler, 1 cm = 12 km in reality.
• Numerical scales use a ratio or fraction to show reduction (e.g.,. 1:200,000)
• Numerical Scale- 1:200,000 means the reality was reduced 200,000 times.
• Numerical Scale- 1 cm on the map equals 200,000 cm on the map.
• Scale conversion use, transforming centimeters (map) to kilometers (reality), requiring knowledge of metric conversions.
• Metric conversions needed, but a shortcut is adding/removing five zeros when converting between kilometers and centimeters.
• When converting Km to cm add five zeros
• When converting cm to Km remove five zeros
• Large scale maps show more detail but smaller areas.
• Small scale maps show less detail but larger areas.
• Confusingly, a 1:6 scale is "larger" than a 1:1,000,000 scale because its denominator is smaller showing more details.

Map Projections

• Projections represent the Earth on a flat surface, which always involves distortion.
• Globes are accurate but impractical for atlases or comparisons.
• Map conventions are ideological, for instance placing Europe at the top is a choice.
• Map projections have three main types: cylindrical, conic, and azimuthal.
• Cylindrical projections wrap a cylinder around the globe.
• The cylindrical projection is a rectangle, with parallels and meridians at 90°.
• The cylindrical projection always has little distrotion at the equator and extreme distortion at the poles.
• Conic projections place a cone over the globe and distort areas far from the tangent.
• Conic projections are best or areas in temperate zones.
• Azimuthal projections put a flat plane over the globe so distortion increases away from the center.
• Azimuthal projections are good for geopolitical maps and polar regions.
• Azimuthal projections have a centre with little distortion, but distortion increases in areas futher away.
• The UN map uses an azimuthal projection, which can prioritize developed countries.

Map Properties

• No map can preserve all properties- area (equivalence), distance (equidistance), and shape (conformity) simultaneously.
• Mercator Projection is a conformal cylindrical map used in navigation, with shapes preserved nut distorts area.
• In a Mercator Projection the shapes are preserved but the areas are distored and the distances are not accurate.
• Example: Greenland appears larger than South America on a Mercator map.
• Mercator maps placed Europe in the center-top, which can be seen as ideologically biased.
• Peters Projection- is an equal-area map, correcting area distortions but shapes are distorted.
• Peters Projection presents all areas accurately.
• Peters Projection has a "Third World" focus by accurately representing the sizes of developing countries.

Isolines

• Isolines connect points of equal value, such as rainfall or pressure.
• Contours connect points of the same altitude and help see the relief of a landscape.
• Contour separation represents equal distance, indicating steep or gradual slopes.
• Contour lines close together show a steep incline.
• Distant contour lines show a gradual slope.
• Closer contours is more significance/intense variation

Explore the basics of cartography, including map-making as a form of visual communication. Understand essential map elements like title, scale, legend, and orientation. Learn how maps convey information and the importance of standardization in cartography.