Sinkholes are holes that suddenly appear in the ground. They can be any size but some are enormous. Some have swallowed cars, parts of buildings and even people. There are terrifying videos online of football pitches being sucked into the ground, or the resulting huge circular chasms in the middle of cities. They are found all over the world but some parts of the world are more prone to them than others.

In this episode BBC climate and science reporter Esme Stallard answers our questions about what causes them - and whether you can predict if one is going to happen.

In China, the sink holes there are actually different from the rest of the world. Devra Willingham, from the National Cave and Karst Research Institute in the US, tells us why and what it’s like to go into one.

And we examine if climate change is making sinkholes more common.

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