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Understand GIS, satellite observations and geographic data methods.
GIS & remote sensing · Explainers
A red forest in a satellite image is not necessarily burning, and a dark patch is not automatically water. The first task is to find out which measurements…
GIS & remote sensing · Explainers
Remote sensing measures objects or areas from a distance, without direct contact. Passive sensors detect energy reflected or emitted by the scene; active sensors transmit a signal and…
GIS & remote sensing · Comparisons
Raster data divide space into rows and columns of cells, each holding a value. Vector data represent features with coordinate-based geometry, commonly points, lines and polygons, linked to…
Geography basics · Explainers
GIS stands for geographic information system. It combines location-based data with tools for storing, checking, analyzing and displaying that information. A map is one possible result. The broader…
GIS & remote sensing · Quizzes
Take this remote sensing quiz to test how observations become evidence about Earth. Work through 20 questions on sensors, image resolution and interpretation, with an explanation after every…
GIS & remote sensing · Quizzes
Test your spatial reasoning with this GIS quiz: 24 questions on geographic data, analysis and the limits of mapped evidence. Work through practical scenarios, check each explanation and…