Grade 10 Geography – Geographic Information Systems (GIS) Quiz

GIS combines maps (spatial data) and attribute data to store, analyse and display information — for example mapping schools in Nairobi and showing their enrolment numbers.

A working GIS needs computers (hardware), GIS programs, trained people, geographic data and agreed methods—together they let users analyse problems like flood risk in the Tana River basin.

Vector data use points (e.g., a borehole), lines (e.g., a road) and polygons (e.g., a county) to represent features with precise shapes and locations.

Rasters are made of pixels each with a value (e.g., colour or elevation) and are used for images and surfaces like Landsat photos or DEMs used to map Mount Kenya slopes.

GPS satellites and most global datasets use WGS84 as the reference datum for latitude and longitude, so it is the standard when collecting locations in Kenya with GPS.

Georeferencing places an old paper map or aerial photo into the correct coordinate system so it can be used with other spatial layers, for example matching old land-use maps to current satellite images of the Rift Valley.

Attribute data describe features shown on a map (e.g., a school feature may have attributes for name, pupil numbers and type), and are used to query and symbolise maps.

Buffers create areas (e.g., 100 m) around features so you can find which houses or farms lie within the flood-prone zone near the river.

Overlay tools let you combine layers (e.g., soils and rainfall) to see where conditions match criteria, which helps in planning agriculture or conservation in areas like the Lake Victoria basin.

A DEM stores elevation for each grid cell and is used for slope, aspect, watershed and hillshade analyses, useful for planning roads in hilly areas like around Mount Kenya.

Landsat provides free medium-resolution satellite images over time and is widely used to study land-use change, forest cover and urban growth in Kenyan cities and countryside.

QGIS is free to download and widely used in schools and organisations in Kenya to teach mapping, digitising, and analysing geographic data.

Shapefiles (.shp plus supporting files) are used to store vector features like county boundaries or road networks together with attributes such as names and IDs.

Scale 1:50,000 means 1 unit on the map equals 50,000 of the same units on the ground. So 1 cm = 50,000 cm = 500 m.

Obstructions like buildings in Nairobi's central business district or dense tree cover cause multipath errors and reduce GPS accuracy; atmospheric conditions and satellite geometry also affect accuracy.

Geocoding turns addresses or place names (e.g., a school name in Kisumu) into coordinates so they can be mapped and analysed in GIS.

Topology ensures correct spatial relationships (for example roads connect properly or polygons do not overlap) which is important for routing and analysing networks in towns like Mombasa.

An attribute join attaches additional data (e.g., census figures) to spatial features using a matching field so you can map and analyse the combined information.

Clip cuts a layer to the shape of another (for example extracting the area of a county from a national land-cover map) so you only work with the area of interest.

Remote sensing uses sensors on satellites (like Sentinel) or planes to collect data such as vegetation health or urban growth without needing to visit every location on the ground.

Select by location finds features that meet spatial criteria (within, intersect, contain) useful for tasks like finding villages near flood zones.

Hillshade simulates light and shadow on terrain from a DEM, helping map readers see slopes and landforms which is useful for planning roads in hilly places.

Interpolation uses nearby observations to predict values across an area (for example estimating rainfall in parts of the Rift Valley where there are few stations).

Metadata tells you who created the data, when and how accurate it is—important to check before using a map layer for tasks like planning school routes or studying land change in your county.

OpenStreetMap is an open, community-driven mapping platform used in Kenya and worldwide to map roads, buildings and services quickly for planning and during emergencies.