Using 3D Laser Scanning Technology to Create Digital Models of Hailstones

• Published in: Bulletin of the American Meteorological Society Vol. 98; no. 7; pp. 1341 - 1348
• Main Authors: Giammanco, Ian M., Maiden, Benjamin R., Estes, Heather E., Brown-Giammanco, Tanya M.
• Format: Journal Article
• Language: English
• Published: American Meteorological Society 01-07-2017
• Subjects: Aerodynamics; IN BOX INSIGHTS and INNOVATIONS; Optical scanners; Radar
• ISSN: 0003-0007; 1520-0477
• DOI: 10.1175/BAMS-D-15-00314.1

The emergence of 3D scanning technologies has provided a new opportunity to explore the shape characteristics of hailstones in great detail. The ability to effectively map the shape of hailstones will improve assessments of hailstone aerodynamic properties, how their density relates to their strength, and how radar energy is scattered. Ultimately, 3D scanning of hailstones will contribute toward research in hail detection, forecasting, and damage mitigation of severe hail, which accounts for well over $1 billion in annual insured losses.
The use of a handheld 3D laser scanner in a field setting was explored during field campaigns in 2015 and 2016. Hailstones were collected following thunderstorm passages and were measured, weighed, and scanned. The system was successful in capturing 3D models of more than 40 hailstones. A full scan takes approximately 3 minutes to complete, and data can be captured at a resolution of 0.008 cm. It is believed this is the first time such a system has been used to produce 3D digital hailstone models. Analysis of the model data has shown that hailstones depart from spherical shapes as they increase in diameter, and that bulk density and strength show little correlation. While the dataset presented here is small, the use of 3D scanners in the field is a practical method to obtain detailed datasets on hailstone characteristics. In addition, these data could be used to 3D-print hailstones to explore their aerodynamics, to produce cavity molds for ice impact tests, and for modeling radar scattering properties of natural hailstone shapes.