"ERA5 137-Level Atmospheric Refraction Coefficient Validation (ERA5-Land Surface Anchor) for the OERK/Riyadh Levelling Corridor (RCD_PLO Campaign, June–August 2012)

Nine-date atmospheric refraction coefficient (kappa) values computed from the ERA5 137-level profile with an ERA5-Land surface anchor, for the RCD_PLO Riyadh levelling corridor (OERK), covering the June-August 2012 field campaign dates. Computed via the KAPPA Arc V4 backend using Smith-Weintraub refractivity and OLS regression on a composite ERA5-Land near-surface / ERA5 L137 profile. Mean kappa 0.19342 against the field-measured campaign value 0.1977 (mean gap 2.2%, range 0.4-3.4%). This dataset backs the revised Table 1 of the corresponding Geodesy and Geodynamics manuscript. The file includes full computational provenance (endpoint, backend version, run date, and cache-status confirmation). Field reference: Al-Kherayef et al. (2018), RCD_PLO project, FIG Congress Istanbul, Paper 9488.