Fig. 3: Estimated flow-enhancement factors for radar-derived and modelled crystal orientation fabric (COF) compared to isotropy.

Flow-enhancement factors for along-flow pure-shear compression/extension (a–c) and horizontal shear deformation (d–f). Both compressional/extensional and shear enhancement factors are calculated from the COF estimates obtained from travel-time differences (a, d), beat-signature analysis (b, e), and Elmer/Ice-flow modelling (c, f). Note that the enhancement factors displayed in this figure are calculated in the eigenframe (COF coordinate system), since the true orientation relative to the flow direction is unknown, although it can be simulated with Elmer/Ice (see Supplementary Information 2.1 and 3). The term ‘along-flow’ therefore, refers to the direction of the smallest horizontal eigenvalue. Background in all panels shows satellite-based surface velocities⁶⁴.