Skip to content
Kharita Challenges

Learning paths

Each path is an ordered sequence with a stated outcome — something you will be able to do, not a topic you will have covered.

Track
Spatial Analysis3 pathsPostGIS / SQL1 pathPython1 pathRemote Sensing1 pathCartography2 pathsData Management2 paths

2 of 10 paths

  1. A world map that tells the truth

    Cartography

    Take a global boundary layer and make defensible maps and lists from it: quantify projection distortion, shade a rate rather than a count, audit identifiers and geometry before joining on them, and apply an area rule across borders in an equal-area projection.

    The countries layer as a working dataset: what a projection does to area, what normalisation does to a choropleth, what generalisation does to a coastline, and the audits that decide whether the layer can be trusted for the job.

    5 steps · ~3 h · 1,100 XP

    Begins with How big does Web Mercator make Greenland?

    Start: How big does Web Mercator make Greenland?
    Show the 5 steps
    1. How big does Web Mercator make Greenland?intermediateDifficulty: intermediate~30 min
    2. Normalise the map before you shade itbeginnerDifficulty: beginner~25 min
    3. Which airport codes will break the schedule join?beginnerDifficulty: beginner~25 min
    4. Are these country polygons fit to assign cities to?advancedDifficulty: advanced~45 min
    5. Which metros straddle an international border?advancedDifficulty: advanced~50 min

  2. Make geographic policy maps defensible

    Cartography

    Join and audit country and raster data, choose honest denominators and visual ranges, retain outliers behind a disclosed display cap, and deliver a mapped policy finding with its source limits explicit.

    Rates, missingness, raster evidence, outliers and signed change: turn public geospatial data into maps that a policy reader can question and an analyst can reproduce.

    6 steps · ~5.5 h · 1,980 XP

    Begins with Normalise the map before you shade it

    Start: Normalise the map before you shade it
    Show the 6 steps
    1. Normalise the map before you shade itbeginnerDifficulty: beginner~25 min
    2. Classify a map where most of the values are zeroadvancedDifficulty: advanced~45 min
    3. Accept the rasters, or send them backintermediateDifficulty: intermediate~35 min
    4. Which boroughs have the least tree cover?intermediateDifficulty: intermediate~40 min
    5. Show country CO2 change without losing the outlieradvancedDifficulty: advanced~85 min
    6. Defend a borough greening shortlistadvancedDifficulty: advanced~110 min