Ice dynamics and structural evolution of Jutulstraumen, Dronning Maud Land, East Antarctica (1963-2022)

Abstract

Jutulstraumen is a major outlet glacier in East Antarctica that drains into the Fimbulisen, Dronning Maud Land. Here, we present the first long-term (∼60 years) record of its behaviour using optical satellite imagery. Our analysis reveals that the ice front has been steadily advancing since its last major calving event in 1967, with a steady ice flow velocity of ∼720 ± 66m yr-1 (2000-2021), accompanied by spatially variable thickening of the grounded ice at +0.14 ± 0.04 m yr-1 (2003-2020). We also find evidence to suggest a minor grounding line advance of ∼200 m between 1990 and 2022, albeit with large uncertainties. Mapping of the major rifts on Jutulstraumen's ice tongue (2003-2022) reveals an overall increase in their length, accompanied by some minor calving events along its lateral margins. Given the present-day ice front advance rates (∼740 m yr-1), the ice tongue would reach its most recent maximum extent (attained in the mid-1960s), in around 40 years, but extrapolation of rift lengthening suggests that a major calving event may occur sooner, possibly in the late 2050s. Overall, there is no evidence of any dynamic imbalance, mirroring other major glaciers in Dronning Maud Land