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Films · Geography · Land subsidence

Explainer · Geography

The ground beneath the city is sinking

The end

The ground beneath the city is sinking

Large cities sink because pumping permanently compacts the clay below them. Radar satellites measure it to the millimetre, and only pumping less stops it.

Chapter 1 · Cities are sinking

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The ground beneath the city is sinking

Geography · Land subsidence

NewOct 18, 2026 · 4 chapters

An explainer film in four chapters on sinking cities: how fast the ground sinks beneath large cities, what happens in the clay when a city pumps groundwater, how radar satellites measure millimetres, and what really helps. Pause anywhere and ask.

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  2. AskTap “Ask” and type what you want to know. The answer comes inside the film, with picture and voice.
  3. Steer itTell it what to show, for example “Do this with z = 2 − 3i”. The film sets up the app and works it out.
  4. Try it yourselfWhile it is paused, drag points and sliders yourself. “Continue” takes you back into the film.

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