This study presented new annual maps of irrigated cropland in China from 2000 to 2020 (CIrrMap250). These maps were developed by integrating remote sensing data, irrigation statistics and surveys, and an irrigation suitability map. CIrrMap250 achieved high accuracy and outperformed currently available products. The new irrigation maps revealed a clear expansion of China’s irrigation area, with the majority (61%) occurring in the water-unsustainable regions facing severe to extreme water stress.

Little knowledge exists about whether students can improve their understanding of disaster risk reduction (DRR) through web geographic information system (GIS) technology and which factors affect their learning. This study has provided materials and curricula for DRR education in Chinese and Japanese high schools. The daily use of online maps and attention to disaster prevention affect the learning of all the materials. Increasing the use of online hazard maps is key to realizing social DRR.