Predicting Antarctic Net Snow Accumulation at the Kilometer Scale and Its Impact on Observed Height Changes

• Published in: Geophysical research letters Vol. 49; no. 20; pp. e2022GL099330 - n/a
• Main Authors: Medley, B, Lenaerts, J T M, Dattler, M, Keenan, E, Wever, N
• Format: Journal Article
• Language: English
• Published: Goddard Space Flight Center Wiley 28.10.2022; John Wiley & Sons, Inc; John Wiley and Sons Inc
• Subjects: Abrupt/Rapid Climate Change; Accumulation; Air/Sea Constituent Fluxes; Air/Sea Interactions; Airborne radar; Airborne remote sensing; altimetry; Antarctic ice sheet; Antarctica; Atmospheric; Atmospheric Composition and Structure; Atmospheric Effects; Atmospheric models; Atmospheric Processes; Avalanches; Benefit‐cost Analysis; Biogeosciences; Blowing snow; Climate and Interannual Variability; Climate Change and Variability; Climate Dynamics; Climate Impact; Climate Impacts; Climate Variability; Climatology; Computational Geophysics; Cryosphere; Cryospheric Change; Decadal Ocean Variability; Disaster Risk Analysis and Assessment; Earth System Modeling; Earthquake Ground Motions and Engineering Seismology; Effusive Volcanism; Elevation; Explosive Volcanism; General Circulation; Geodesy and Gravity; Geological; Glaciation; Glaciology; Global Change; Global Change from Geodesy; Gravity and Isostasy; Height; Hydrological Cycles and Budgets; Hydrology; Ice; Ice Sheets; Ice Shelves; Impacts of Global Change; Informatics; Land/Atmosphere Interactions; Marine Geology and Geophysics; Mass Balance; Meteorology and Climatology; Modeling; Modelling; Mud Volcanism; Natural Hazards; Numerical Modeling; Numerical Solutions; Ocean influence of Earth rotation; Ocean Monitoring with Geodetic Techniques; Ocean/Atmosphere Interactions; Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions; Oceanic; Oceanography: General; Oceanography: Physical; Oceans; Paleoceanography; Physical Modeling; Physiographic features; Policy Sciences; Radar; Radar data; Radio Oceanography; Radio Science; Regional Climate Change; Regional Modeling; Remote Sensing; Research Letter; Risk; Satellites; Sea Level Change; Sea Level: Variations and Mean; Seasonal variations; Seismology; Snow; Snow accumulation; Snow and Ice; Snow transport; Snowfall; Solid Earth; Sublimation; surface mass balance; Surface Waves and Tides; The Ice, Cloud and land Elevation Satellite‐2 (ICESat‐2) on‐orbit performance, data discoveries and early science; Theoretical Modeling; Topography; Transport; Tsunamis and Storm Surges; Variability; Volcanic Effects; Volcanic Hazards and Risks; Volcano Monitoring; Volcano Seismology; Volcano/Climate Interactions; Volcanology; Water Cycles; Antarctica; Antarctic; Altimetry; Surface Mass Balance; altimetry; surface mass balance
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2022GL099330

Sub-grid-scale processes occurring at or near the surface of an ice sheet have a potentially large impact on local and integrated net accumulation of snow via redistribution and sublimation. Given observational complexity, they are either ignored or parameterized over large-length scales. Here, we train random forest (RF) models to predict variability in net accumulation over the Antarctic Ice Sheet using atmospheric variables and topographic characteristics as predictors at 1 km resolution. Observations of net snow accumulation from both in situ and airborne radar data provide the input observable targets needed to train the RF models. We find that local net accumulation deviates by as much as 172% of the atmospheric model mean. The correlation in space between the predicted net accumulation variability and satellite-derived surface-height change indicates that surface processes operate differently through time, driven largely by the seasonal anomalies in snow accumulation.