13 oktober 2025
Satellite technology reveals true scale of extreme storms and corrects decades of wave energy estimates
Sea State data from ESA’s Climate Change Initiative helps to validate wave models
Satellite measurements prove what scientists suspected: ocean swells act as storm 'messengers', carrying destructive energy thousands of kilometres across the ocean to coastlines far from where the weather system originated. This means coastal communities and marine infrastructure face threats even when storms never make landfall.
New findings demonstrate that the energy content of very long ocean waves has been systematically overestimated: more energy concentrates in dominant storm waves, while very long swells carry less energy than previously assumed.
On 21 December 2024, the French–US Satellite Water and Ocean Topography (SWOT) satellite captured average wave heights exceeding 19 metres during Storm Eddie – the largest ever measured from space, providing the first direct validation of numerical wave models under extreme conditions.
The study's authors, including Fabrice Ardhuin from the ESA CCI Sea State team, tracked the swell across 24,000 km from the North Pacific to the tropical Atlantic. Analysing this event alongside ESA's Climate Change Initiative Sea State dataset – 34 years of observations from 14 satellite missions including Copernicus Sentinel-3, Sentinel-6 and CryoSat – the team validated numerical wave models under extreme conditions for the first time. This validation enabled researchers to correct energy calculations that coastal engineers use to design protective infrastructure for coastal communities.
Read the full article about the study's findings and methodology:
