![]() ![]() Recent studies have revealed that the acceleration of ice calving events from polar ice shelves plays a vital role in sea-level rise ( Rignot and Kanagaratnam, 2006 Rignot et al., 2011). While drifting, icebergs melt, bringing freshwater that affects the local freshwater budget and the environment ( Gladstone et al., 2001 Silva et al., 2006 Stern et al., 2015 Moon et al., 2018). During their life span, they drift and rotate due to forces from winds, waves and ocean currents. Icebergs calve off glaciers in cold polar regions. Combining the iceberg shape rendering and the surrounding environmental measurements, we estimated the iceberg melting parameters due to the sensible heat flux and surface wave erosion at different iceberg sections. ![]() We have observed water upwelling and a colder and fresher water plume at the sea surface downstream the iceberg. ![]() During the field experiment, additional oceanographic measurements, such as temperature, ocean current, and wind, were collected simultaneously by the USV. The resulting motion estimates are then used to reconstruct the iceberg shape. When applying the motion estimation algorithm to these two independent point cloud measurements collected by the two sensing modalities, consistent iceberg motion estimates are obtained. In the field data, the above-water iceberg surface was measured with a scanning LIDAR, while the below-water portion (0–50 m) was profiled using a side-looking multi-beam sonar. The motion estimation algorithm is applied to a simulated data set and field measurements collected by an Unmanned Surface Vehicle (USV) on a free-floating, translating, and rotating, iceberg. A down-sampling method is also integrated to reduce the processing time for possible real-time applications. The algorithm is developed based on point cloud matching strategies, policy-based optimization, and Kalman filtering. In this paper, we present an algorithm for iceberg motion estimation and shape reconstruction based on in-situ point cloud measurements. ![]() Iceberg shape is one of the most critical parameters in these models, but it is challenging to obtain because of iceberg movement caused by winds, waves, and currents. Iceberg drift and deterioration models have been developed to better predict climate change and protect offshore operations. In addition, drifting icebergs pose threats to offshore operations because they could damage offshore installations, e.g., pipelines and subsea manifolds, and interrupt marine transportation. The increased influx of freshwater ice due to increase calving from ice shelves and the destabilization of the continental ice sheet will affect sea levels globally. Besides the impacts to local ecosystems due to changes in seawater salinity and temperature, the freshwater influx and transport can have significant regional effects related to the ocean circulation. The calving, drifting, and melting of icebergs has local, regional, and global implications. 3Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St.2MARUM, University of Bremen, Bremen, Germany.1Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, United States.Mingxi Zhou 1 * Ralf Bachmayer 2 Brad DeYoung 3 ![]()
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