Reproduction artifacts for point-wise inference of basal friction in the Amundsen Sea sector

Reproduction artifacts for the Journal of Glaciology manuscript "Do ice and subglacial observables determine basal friction? A point-wise test in the Amundsen Sea sector". Contents: non-NSIDC scientific inputs, mesh and regional boundaries, the frozen experiment design, the accepted sector-wide inversion evidence, the canonical MLP dataset and exact split definitions, 660 verified MLP training runs, the blinded L2 calibration, 66 median basal-friction controls with their Icepack modeled velocities and uniform-control baselines, the 76 controlled-replacement forward solves and their corrected evaluation, the analysis-ready outputs and figure sources used in the manuscript and appendix, and a transfer-predictability analysis testing whether the predictors can indicate in advance where the predicted basal-friction control improves modeled velocity. Seven gzipped tar archives, 8.68 GB total. Archives 01-05 are the 16 September 2026 build; archive 06 holds the 17 September 2026 controlled-replacement correction, which restricted where predicted or uniform C replaces the inversion-reference control to each withheld footprint or corridor intersected with the common eligible grounded mask, re-evaluated velocity RMSE against the original paired MEaSUREs raster components, and added four controlled inter-catchment solves. No inversion, MLP training or L-curve selection was rerun for that correction, so archives 01-05 are unchanged by it. Where archives 04 and 06 cover the same quantity, archive 06 is the reported value. Archive 07 (19 September 2026) adds the transfer-predictability analysis and changes nothing in archives 01-06; its additional per-row error fields were produced by interpolating the saved archive-06 velocities, with no solve rerun. BedMachine Antarctica v2 and the MEaSUREs phase-based velocity mosaic are not redistributed here. They remain available from NSIDC and are identified by exact SHA256 in the code repository. SHA256SUMS.txt lists the checksum of every archive. The code repository's scripts/verify_artifacts.py and scripts/unpack_artifacts.py verify and unpack all seven archives once they sit in one directory.