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  • 🀚Before We Start
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  • 🌎Cartographic Systems
    • Projections
    • Positioning Systems
    • Coordinate Reference Systems
  • πŸ“Spatial Analysis
    • Normalization
    • Ecological Fallacy
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  • The Web Mercator Projection
  • Why It Matters for Environmental Justice
  • Guidance on Selecting the Right Projection
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  1. Cartographic Systems

Projections

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Last updated 1 year ago

Geographic projection systems are methods used to represent the round surface of the Earth on flat maps. Because the Earth is a sphere, it's impossible to show its surface on a map without some distortion of area, shape, distance, or direction. Projection systems help to manage these distortions depending on the purpose of the map. When we turn our round Earth into a flat map, . Each projection method currently available to make a map can only keep one or two of these accurate, but not all at the same time.

The Web Mercator Projection

Why It Matters for Environmental Justice

Choosing the right map projection is crucial for environmental justice efforts. Accurate maps help ensure fair and equitable resource distribution, environmental planning, and policy-making. For instance, projections that distort land sizes can misrepresent the true scale of a problem, like deforestation or pollution, affecting local communities, particularly those in less affluent regions. Having accurate, fair maps ensures that these issues are seen and treated with the urgency they require.

Guidance on Selecting the Right Projection

Selecting the right projection depends on the map’s purpose. For local-scale projects, it's important to choose projections that accurately reflect land shapes and sizes to avoid misrepresenting the geographical context. For global maps, one might choose projections that balance between distortions across various dimensions. Always consider the audience and purpose: is the map for navigation, statistical representation, comparative studies, or educational purposes? Consulting with a GIS professional can also help in making informed decisions about which projection to use for your specific needs.

Interactive online maps, like the ones we use on our phones and computers, add another layer of complexity in this area. These maps into small, manageable squares for our screens also known as the 'Web Mercator.' This Mercator is different from the one used in traditional, large-scale maps, as simplifications were made for simplicity and speed on the web (). While this projection is useful for browsing maps online, and is . (Note: Web Mercator is currently used in Google Earth, Bing, CARTO, OpenStreetMap, and ArcGIS Online.)

Historical and contemporary biases are evident in the persistence of the . This distortion not only reflects but also perpetuates imperialist and Eurocentric narratives, underscoring the projection's ethical quandaries.

Acknowledgments:

Art:

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use "tiling" to break down the whole world
How to Lie with Maps
it's inaccurate when measuring distances or areas
difficult to change
Mercator projection, which disproportionately enlarges regions in the Northern Hemisphere, mainly Europe and North America, at the expense of countries in the Global South
Aaron Adams
Fanesha Fabre
we alter four key things: shape, size, distance, and direction
Round things and flat things don't mix.
Young black man trying to wrap a ball unsuccessfully