It was April 14, 1986 when Gopalganj district, in Bangladeshwas hit by a devastating hailstorm. A tragedy that not only caused 92 victims, but left an indelible mark on meteorological history. Those hailstones, according to the World Weather and Climate Extremes Archiveweighed up to 1.02 kilograms each. A world record that made that day unforgettable, unfortunately for the worst reasons.
It is nothing new that extreme weather phenomena are becoming more and more frequent. Climate change accelerates processes that seem unstoppable to us, such as the formation of giant hailstones. It is precisely with this scenario in mind that a group of researchers decided to analyze the exceptional hailstorm that occurred in Catalonia in 2022. The objective? Understand the mechanisms underlying these storms and anticipate future scenarios.
Science meets ingenuity
This time, science had a small advantage. Some inhabitants of Catalonia, aware of the exceptional nature of the storm, kept some specimens of hail in their freezers, including a colossus 12 centimeters in diameter. It was thanks to these samples that researchers at the University of Barcelona were able to apply an innovative technique: computed tomography, as explained by Professor Xavier Úbeda:
We were looking for a method that would allow us to analyze the internal stratifications without damaging the samples.
The imagination, in this case, exceeded expectations. The scans showed detailed images of the internal structures of the hailstones, revealing a development that was anything but smooth. Even the most spherical hailstones, in fact, hide a nucleus, or “embryo”, positioned in a way that is anything but central.
Professor Javier Martin-Vide, co-author of the study, said:
This technique allows us to understand the formation processes by analyzing the growth layers of hailstones
A non-invasive observation that could prove crucial to improve forecasts and prevent tragedies related to extreme weather events.
The doctor Carme Farnell Barqué of the Meteorological Service of Catalonia concluded:
For the first time we were able to observe the entire internal structure of hailstones, obtaining fundamental clues to improve our understanding of the phenomenon.
The images captured through CT scans are a window into how these ice spheres form under specific conditions. But most of all, they are an invitation to reflect on the crucial role of scientific research in an era of increasingly evident climate change. Preparing for extreme events such as giant hailstorms is not just a question of technology, but of collective responsibility.
