1. National Disaster Reduction Center of China, Ministry of Civil Affairs, No.1, Guangbai Eastern Road 6, Chaoyang District, Beijing, 100124, China; and College of Geography and Remote Sensing Science, Beijing Normal Univ., Beijing, 100875, China (corresponding author).
2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal Univ., Beijing, 100875, China.
3. Key Laboratory of Regional Geography, Beijing Normal Univ., Beijing, 100875, China; and College of Geography and Remote Sensing Science, Beijing Normal Univ., Beijing, 100875, China.
4. Key Laboratory of Regional Geography, Beijing Normal Univ., Beijing, 100875, China.