ICE VELOCITY MEASUREMENT IN EAST ANTARCTICA FROM 1960s TO 1980s BASED ON ARGON AND LANDSAT IMAGERY

Abstract

ABSTRACT:Ice flow velocity is a vital parameter for estimating the ice mass balance of glaciers in Antarctica. Especially long time serial observation of the surface velocity is of great significance to assessing the relationship between Antarctic ice materials and global climate change. However, the existing research on Antarctic ice velocity based on remote sensing data since 1970s due to the harsh climate in Antarctica. This paper presents an ice flow velocity estimating method includes image pre-processing, geometric model reconstruction, image ortho-rectification and feature matching by using ARGON images token in 1963 and Landsat images collected form 1973 to 1989.Considering the temporal-spatial distributions of ARGON images and Landsat images in Antarctica, two different methods respectively based on ortho-photos pair and Non-Ortho photos are adopted in this paper. More specifically, when there exist two stereo pairs taken in different time in the glacier region, after being ortho-rectified, the stereo pairs can be used to calculate ice flow velocity based on feature matching method. Otherwise, a parallax decomposition method that separates the effect of the terrain relief from the ice flow motion is applied when there only exists one stereo pair with a certain time interval. With this method, glacier surface velocity is available in the glacier region lacked enough stereo pairs. The methods mentioned above for estimating ice flow velocity are applied in Totten, Amery and Fimbul, etc. in eastern Antarctica. Furthermore, a 1960-80s ice flow speed map in the main glaciers of East Antarctica is produced for the first time.

Ice Flow Velocity Mapping for Long-Time Motion Analysis of Typical Glaciers in Northwestern Greenland

“…In this paper, we used the image matching approach described by Li et al [9]~ [10]. Based on this technique, we proposed feature points and grid point hierarchical matching, as well as triangulation limitations, to increase matching point density and accuracy.…”

“…However, due to the complexity of its matching technique, it has not been widely used for mapping the ice flow velocity of Greenland glaciers. In recent years, Li et al [9]~ [10] and Ye et al [11] proposed three methods for reconstructing the ice flow velocity field of glaciers in East Antarctica from the 1960s to the 1980s based on DISP and Landsat images, which could also be applicable for mapping ice flow velocity in the early period in northwestern Greenland. In this paper, the above data and methods were used to map the historical ice flow velocity maps of four typical glaciers in northwestern Greenland and analyze the changes in both ice flow velocity and ice front.…”

Surface topography modelling and ice flow velocity mapping of Dalk Glacier, East Antarctica: application of UAV remote sensing

“…We used the Image Geo-Rectification and Feature Tracking software (ImGRAFT: http://imgraft.glaciology.net) and the image matching techniques proposed by Li et al (2017) to derive ice velocity fields for Dalk Glacier.…”