Historical Ice Velocity Mapping of Pine Island Glacier, West Antarctica, Using Landsat and KH-9 Hexagon Data

The Pine Island Glacier (PIG) is becoming increasingly unstable as a result of global warming, with profound implications for Antarctic mass loss and sea level rise. To study the mass balance of the Antarctic Ice Sheet, accurate ice flow velocity data are essential. However, ice flow velocity products for this glacier are mainly available after the 1990s. We proposed an ice flow velocity estimating method that includes image pre-processing, image orthorectification and hierarchical matching based on Landsat and KH-9 Hexagon images. In this study, a map of the ice flow velocity of the PIG from 1973 to 1975 is generated using these images, allowing the time span of the PIG ice flow to be extended to the 1970s. The results show that the ice flow velocity has increased and in an accelerated state since the 1970s. The results offer a perspective for the study of PIG dynamics and provide a basis for estimating changes in the mass balance.