Pre-registration amendment v3 (L1C calibration result and exploratory declarations): When snow looks like water: wet-snow false floods in winter Sentinel-1 flood mapping of the Tensift basin (High Atlas, Morocco)

Amendment v3 to the pre-registration (v1 10.5281/zenodo.23130459; v2 10.5281/zenodo.23144531). L1C/L2A calibration gate on the held-out pilot winter: κ 0.800 [0.698–0.881], 321 snow pairs, 93.9% L1C visibility (≥ 1,500 m), so the 9-winter analysis is primary. It includes a declared correction of an implementation error in a supporting calibration script (found on an empty first output, before any value existed) and exploratory declarations E1 (Donchyts HAND), E2 (Groundsource case studies), E3 (frozen pilot SAR-only snow screen), B1 (detector-independent water frame), B5 (ERA5 winter context) and B6 (incidence-angle band). Published before any confirmatory winter is re-extracted and before any H1–H6 quantity is computed. Contact: [email protected]