From ice core to ground-penetrating radar: representativeness of SMB at three ice rises along the Princess Ragnhild Coast, East Antarctica

• Published in: Journal of glaciology 2022-12, Vol.68 (272), p.1221-1233
• Main Authors: Cavitte, Marie G.P., Goosse, Hugues, Wauthy, Sarah, Kausch, Thore, Tison, Jean-Louis, Van Liefferinge, Brice, Pattyn, Frank, Lenaerts, Jan T.M., Claeys, Philippe
• Format: Article
• Language: English
• Subjects: Accumulation; Antarctic glaciology; Antarctic ice sheet; Climate models; Constraint modelling; Core drilling; Cores; Firn; Footprints; Glaciation; Ground penetrating radar; Ice; ice core; Ice cores; ice rise; Ice sheets; Ice shelves; Mass balance; Radar; Radar data; Records; Resolution; Sea level; Sea level changes; Sea level rise; Temporal resolution; Temporal variability; Temporal variations; Topography; Trends; Wind
• ISSN: 0022-1430; 1727-5652
• DOI: 10.1017/jog.2022.39

The future contributions of the Antarctic Ice Sheet to sea level rise will depend on the evolution of its surface mass balance (SMB), which could amplify/dampen mass losses increasingly observed at the ice sheet's edge. In situ constraints of SMB over annual-to-decadal timescales consist mostly of firn/ice cores that have a surface footprint $\sim$cm$^{2}$. SMB constraints also come from climate models, which have a higher temporal resolution but a larger surface footprint of several km$^{2}$. We use ice-penetrating radar data to obtain an intermediate spatial and temporal resolution SMB record over three ice rises along the Princess Ragnhild Coast. The co-located ice cores allow us to obtain absolute radar-derived SMB rates at a multi-annual-to-decadal temporal resolution. By comparing the ice core SMB measurements and the radar-derived SMB records, we determine that pointwise measurements of SMB are representative of a small surface area, $\sim 200-500$ m radius extending from the ice core drill site for the ice rises studied here, and that the pointwise measurements are systematically 7–15 cm w.e. a$^{-1}$ lower than the mean SMB value calculated for the whole ice rises. However, ice core records are representative of an entire ice rise's temporal variability at the temporal resolution examined.