A study on the flood risk influenced by climate changes in the Lixiahe region, China

摘要

Flood happens frequently in Lixiahe region of Jiangsu Province, China, which is caused by rainstorms, the flat terrain and bad drainage conditions. And floods tend to be more severely influenced by climate changes during recent years. The paper investigated the abnormal climate conditions which causes storm floods, analyzed the correlation between the rainstorm process and water levels, and calculated the inundated water level and area. The research indicated that the following: (1) There is a linear relationship between the cumulative runoff depth of single rainstorm with the daily average water level; (2) The flood inundated area has been greatly increased when the precipitation is greater than 20 years return period in the Lixiahe region; (3) The anomalies of subtropical high intensity may cause precipitation to increase abnormally, resulting in high water level in the Lixiahe region; and the abnormal movement of subtropical ridge line position can be used as an important basis for the flood forecasting of Lixiahe region.