ICE FLOW VELOCITY MAPPING IN EAST ANTARCTICA USING HISTORICAL IMAGES FROM 1960s TO 1980s: RECENT PROGRESS

Abstract

Abstract. Recent research indicates that the estimated elevation changes and associated mass balance in East Antarctica are of some degree of uncertainty; a light accumulation has occurred in its vast inland regions, while mass loss in Wilkes Land appears significant. It is necessary to study the mass change trend in the context of a long period of the East Antarctic Ice Sheet (EAIS). The input-output method based on surface ice flow velocity and ice thickness is one of the most important ways to estimate the mass balance, which can provide longer-term knowledge of mass balance because of the availability of the early satellites in 1960s. In this study, we briefly describe the method of extracting ice velocity based on the historical optical images from 1960s to 1980s. Based on the draft ice velocity map of the EAIS using this method, we conduct a series of validation experiments, including comparisons with in-situ measurement, existing historical maps and rock outcrop dataset. Finally, we use the input-output method to estimate mass balance in some regions of EAIS using the generated velocity map.

Changes in Antarctic Ice Sheet Motion Derived From Satellite Radar Interferometry Between 1995 and 2022

“…Mapping of ice velocity on the ground with theodolites and Global Positioning System has been replaced by satellite techniques, with records spanning from the early days of Corona/Argon (Li et al., 2017; Luo et al., 2021) in the 1960s, Landsat‐1 (Rignot et al., 2019) in the 1970s, to the Synthetic‐Aperture Radar (SAR) era of the 1990s with the European Earth Remote Sensing satellites 1 and 2 (ERS‐1, 2), the 2000s with the European Envisat ASAR, the Canadian RADARSAT‐1 and the Japanese Aerospace Exploration Agency Advanced Land Observing System (ALOS) PALSAR, and the mid 2010s with the European Union Copernicus Sentinel‐1a/b series (S1a/b), combined with an improved time series of optical data from Landsat‐8 Operational Land Imagery (OLI) and Sentinel‐2 (S2) (Mouginot et al., 2017).…”

Satellite record reveals 1960s acceleration of Totten Ice Shelf in East Antarctica

“… a Ice flow velocity field from 1963 to 1989 with glacier and ice shelf centerlines marked AA′ and BB′, respectively, Box 1 in shelf front (~50 km from shelf front), Box 2 near grounding line (~4 km from grounding line) and shelf fronts showing the largest retreat during 1973–1989. The gray dashed line is the dividing line between the velocity maps generated in this study and the regional velocity map 29 , 30 . b Velocity difference map (1973–1989 minus 1963–1973), illustrating an ice shelf-wide increase of 60 ± 11 m/y, due to the shelf front retreat.…”

“…The extended area (outside the gray dashed line in Fig. 1a ) is covered by using a regional velocity map 29 , 30 .…”

Multitemporal Structure-from-Motion: A Flexible Tool to Cope with Aerial Blocks in Changing Mountain Environment

“…While at the beginning SfM could be only applied to close-range photos, successive development in processing and computing techniques extended its application to any types of images, see Barazzetti et al (2019). When photogrammetric projects are used for monitoring/detecting changes within time based on the comparison of point clouds (or derived digital elevation models -DEMs; see Lindenbergh and Pietrzyk, 2015) or from surface feature tracking (see Luo et al, 2021), more blocks of images are collected at multiple epochs and processed. Georeferencing each block in the same reference system is fundamental to allow the recognition and quantification of meaningful changes.…”