Effectively Extracting Iceberg Freeboard Using Bi-Temporal Landsat-8 Panchromatic Image Shadows

The freshwater flux from icebergs into the Southern Ocean plays an important role in global climate through its impact on deep-water formation. Large uncertainties exist ice volume transported by due to sparse spatial and temporal coverage of observations, especially observations thickness. iceberg freeboard is a critical geometric parameter for measuring thickness then estimating volume. This study developed new, highly efficient shadow-height method precisely measure various surrounded sea using Landsat-8 Operational Land Imager 15-m bi-temporal panchromatic image shadows at low-solar-elevation angles. We evaluated validated shadow length precision according measurements comparison with unmanned aerial vehicle. determined solar elevation angle. In our case area, 4832 available points better than 2 pixels covered 376 sizes ranging 0.002 0.7 km² 2.3 83.4 m. At angles 5.2°, 64.1% data could reach 1 m 86.9% Our proposed effectively filled gap existing measurement methods.