Imagine rain falling in a different place

A few years ago, in a place quite close to here, a lot of rain fell from the sky. This hurt people and caused problems to their houses. People were not ready. But the rain could have fallen in a different place - maybe a bigger city - or fallen for longer, or fallen over a bigger area. We use computers to make new worlds to try out different possible ways the rain could have fell. You can think of them as several different story lines. We then use these story lines to think about what could have happened, what could happen in a few years, or what we need to be ready for. We also use these story lines to try to understand why some of them rain lots and some don't rain at all. This is important to people - we need to imagine such things to be ready in case they do happen.