ELI5: An ice famine is when people cannot get any ice. This usually happens in places that are really hot and people need ice to stop their food and drinks from getting spoiled.
Back in the olden days, people used to have iceboxes to keep their food cool. These iceboxes were like big wooden cabinets, and they needed blocks of ice to work. People used to cut ice from lakes and rivers during the winter and store it in special buildings called icehouses.
When summer came around, people would buy the ice from the icehouses and use it to keep their food cool. But sometimes, there wasn't enough ice to go around, and that's when an ice famine would happen.
Nowadays, most people have refrigerators to keep their food cool, so ice famines don't really happen anymore. But back in the day, an ice famine could be a big problem, and people would have to find other ways to keep their food from going bad.