Firn Stratigraphic Genesis in Early Spring: Evidence From Airborne Radar

The mapping of internal annual layers in polar firn with ultra-wideband (UWB) surface-based and airborne radars enables the assessment of past snow accumulation amounts and patterns. We used a UWB microwave radar (snow radar) to image and track internal layers in firn over hundreds of kilometers in West Antarctica (WA). We used dated ice-core records to determine that stratigraphic internal layers (SILs) are mainly formed in spring. The analysis uncertainty is generally small, with the highest values associated with regions and/or years with low accumulation. In survey regions with multiple ice-core records, the choice of ice-core record used for the radar analysis was found to have a very small contribution to the overall analysis uncertainty.