Analysis of land subsidence change in Wuhan based on sentinel-1A

Abstract

We used 52-view Sentinel-1A images to obtain the subsidence of Wuhan city by SBAS method during the period of 2020-2021. At present, Hongshan District of Wuhan is the area with the most serious subsidence, and the maximum accumulated settlement reaches 90mm. In addition, there are obvious subsidence funnels in Qiaokou, Qingshan, Jiang’an and Wuchang Districts. Spatial distribution of settlement areas in Wuhan is closely related to urban construction, and the formation of most of the subsidence funnels is related to the high-intensity urban construction activities in the region, with extensive ground subsidence along Metro Line 5 and Metro Line 11. Karst collapse and ground subsidence are more likely to occur in carbonate rock belt and soft soil covered area. Rainfall affects the total amount of groundwater and the river water level in Wuhan. Rainfall can add the groundwater volume, raise the water level of rivers and slow down the rate of ground subsidence in the major subsidence areas of Wuhan.