Antarctic Basal Water Storage Variation Inferred from Multi-Source Satellite Observation and Relevant Models

• Published in: Remote Sensing
• Main Authors: Jingyu Kang, Yang Lu, Yan Li, Zizhan Zhang, Hongling Shi
• Format: Text
• Language: English
• Published: Multidisciplinary Digital Publishing Institute 2022
• Subjects: Antarctica; basal water variation; multi-source satellite; gravity inversion; Antarctic; The Antarctic; Amundsen Sea; East Antarctic Ice Sheet; Siple; Siple Coast; Institute Ice Stream; Rockefeller Plateau; Antarc*; Ice Sheet
• Online Access: https://doi.org/10.3390/rs14102337

Antarctic basal water storage variation (BWSV) refers to mass changes of basal water beneath the Antarctic ice sheet (AIS). Identifying these variations is critical for understanding Antarctic basal hydrology variations and basal heat conduction, yet they are rarely accessible due to a lack of direct observation. This paper proposes a layered gravity density forward/inversion iteration method to investigate Antarctic BWSV based on multi-source satellite observations and relevant models. During 2003–2009, BWSV increased at an average rate of 43 ± 23 Gt/yr, which accounts for 29% of the previously documented total mass loss rate (−76 ± 20 Gt/yr) of AIS. Major uncertainty arises from satellite gravimetry, satellite altimetry, the glacial isostatic adjustment (GIA) model, and the modelled basal melting rate. We find that increases in basal water mainly occurred in regions with widespread active subglacial lakes, such as the Rockefeller Plateau, Siple Coast, Institute Ice Stream regions, and marginal regions of East Antarctic Ice Sheet (EAIS), which indicates the increased water storage in these active subglacial lakes, despite the frequent water drainage events. The Amundsen Sea coast experienced a significant loss during the same period, which is attributed to the basal meltwater discharging into the Amundsen Sea through basal channels.