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Kharita Challenges

Problems

Real geospatial problems, graded automatically. Choose a track, a level and what you want to hand in.

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Spatial Analysis6 problemsPostGIS / SQL0 problemsPython6 problemsRemote Sensing0 problemsCartography0 problemsWeb GIS0 problemsData Management3 problemsGIS Architecture0 problems
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Beginner0 problemsIntermediate0 problemsAdvanced1 problemExpert2 problems
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SQL0 problemsPython3 problemsGeoJSON3 problemsAnswers0 problemsSchema0 problemsDecisions0 problemsDataset file0 problems
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Data preparation2 problemsData quality1 problemSpatial analysis3 problemsRaster analysis0 problemsCartography1 problemDecision support3 problemsGeospatial systems0 problemsWeb delivery0 problems
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Data ManagementSpatial analysisPythonClear all
  1. Not started, How much of each state is built up?Spatial analysisPython

    Overlay the urban footprints on the states in an equal-area projection and credit each side of a state line only what lies on it.

    PythonadvancedDifficulty: advanced320 XP~55 min5 checks

    You hand in a Python script.

    Datasets

    • United States states · Polygon · 51 features · EPSG:4326
    • Urban areas · Polygon · 2,143 features · EPSG:4326

    What you’ll do

    • Reproject both layers to an equal-area CRS
    • Clip the urban footprints to the states with an overlay
    • Sum clipped area per state and express it as a share of the state's area
    GeoPandasoverlayequal-areaAlbersland useAlso trains Spatial Analysis, Data Management
    Open problem
  2. Not started, River kilometres per country, measured on the ellipsoidSpatial analysisPython

    Clip the river centrelines to the country polygons and measure each piece geodesically — no projection is right for a layer that spans the planet.

    PythonexpertDifficulty: expert400 XP~70 min6 checks

    You hand in a Python script.

    Datasets

    • Countries · MultiPolygon · 241 features · EPSG:4326
    • Rivers and lake centrelines · LineString · 461 features · EPSG:4326

    What you’ll do

    • Find every river–country pair that intersects
    • Cut each river to the country polygon
    • Measure the pieces geodesically and sum per country
    GeoPandaspyprojgeodesicoverlayhydrologyglobalAlso trains Spatial Analysis, Data Management
    Open problem
  3. Not started, Screen rivers for a shared-water annexSpatial analysisPython

    Measure mapped river lengths by country and screen the rivers whose courses are meaningfully shared.

    PythonexpertDifficulty: expert650 XP~120 min7 checks

    You hand in a Python script.

    Datasets

    • Rivers and lake centrelines · LineString · 461 features · EPSG:4326
    • Countries · MultiPolygon · 241 features · EPSG:4326

    What you’ll do

    • Intersect every river with every country it touches and measure each piece geodesically
    • Aggregate the pieces per river into a count of meaningful holders and a dominance share
    • Assign the shared rivers, ranked by how evenly they are shared, to result
    GeoPandaspyprojgeodesicoverlayhydrologyglobalAlso trains Spatial Analysis, Data Management
    Open problem