The scientists used a special method to map out when it rains in different parts of China during the summer. They found that certain areas have similar patterns of rain throughout the day, like the North China Plain and the Yarlung Zangbo River valley. By looking at different types of rain events, they discovered that the shape of the land plays a big role in when and how much it rains. This new way of mapping out rain patterns gives us a better understanding of how rain falls in different regions of China.