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CrowdScience listener Eleanor was lying in bed one rainy evening, listening to the radio. She lives in New Zealand, but happened to hear a weather forecast that told her it was raining in the UK too.

She started wondering: could it be the same rain falling there and outside her window in New Zealand? Can a raindrop really travel all the way around the world?

There are a number of routes the droplet could take, including traveling as moisture in the air. Presenter Caroline Steel meets meteorologist Kei Yoshimura, who puts his powerful weather simulation to work plotting the raindrop\u2019s journey through the sky.

What if the raindrop falls along the way and gets trapped? Where might it end up? Hydrologist Marc Bierkens talks Caroline through the detours it could take, ranging from short stop-offs in plant stems to extremely long delays in deep groundwater.

Finally, could the drop of water make it to New Zealand by circulating through the world\u2019s ocean currents? Oceanographer Kathy Gunn maps the droplet\u2019s path through the ocean \u2013 and explains how climate change might affect its journey.

Featuring: \nProf. Kei Yoshimura, Professor of Isotope Meteorology, University of Tokyo \nProf. Marc Bierkens, Professor of Earth Surface Hydrology at Utrecht University \nDr. Kathy Gunn, Lecturer in Climate Sciences at the University of Southampton

Presenter: Caroline Steel \nProducer: Phil Sansom \nEditor: Cathy Edwards \nProduction Co-ordinator: Liz Tuohy \nStudio Manager: Tim Heffer\nAdditional recording: Knut Heinatz

(Photo: Textures of rain on the surface of the ocean. Credit: Philip Thurston/Getty Images)