The satellite laser altimeter can augment the very sparsely populated gauges of rivers. This study validated the water surface elevations of (NASA’s Ice, Cloud, and land Elevation Satellite-2) ICESat-2 ATL13 version 7 from 362 granules (2018-2025) using SEPA (Scottish Environment Protection Agency) stage records for River Dee and River Don, Aberdeenshire, Scotland. From the 1,340 segments selected at or close to each gauge crossing, we have determined the bias of the ATL13 -0.17 m and root mean squared error (RMSE) = 2.36 m for the River Dee, while the bias = -0.92 m and RMSE = 1.36 m for the River Don. Critically, the ATL13 v7 segment quality column 0 is a packed bitmask, not simply an indicator flag as in previous versions; therefore, standard filtering has eliminated all viable river data without any warning. These are the first benchmarks for validating ICESat-2 data for Scottish rivers.
Data and code
All data and analysis scripts are openly available on Zenodo: https://doi.org/10.5281/zenodo.19490053
Submitted to Hydrological Sciences Journal; currently in editor review.
Author: Shobha Mourya Dumpati, FGS, FRGS
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