A rogue wave is a single swell that is much higher than nearby waves and can cause damage to ships and coastal infrastructure. Ocean waves are one of the most powerful natural forces on Earth, and they could become even more powerful as global trends suggest ocean winds will blow even stronger with climate change. there is. Scientists at the University of Melbourne have discovered in a new study that rogue waves are generated by strong winds and unpredictable wave patterns, confirming an idea previously only proven in the lab.
Toffoli other.We report direct observations of surface waves from a stereo camera system and simultaneous measurements of wind speed during an expedition across the Southern Ocean during the Antarctic winter aboard a South African icebreaker. SA Agulhas II. Image credit: Alessandro Toffoli.
“Rogue waves are huge, twice as tall as nearby waves, and appear out of nowhere,” said University of Melbourne’s Professor Alessandro Toffoli, lead author of the study.
Using cutting-edge technology and embarking on an expedition to one of the most unstable ocean regions on Earth, Professor Toffoli and colleagues have introduced a new technique for 3D imaging of ocean waves.
Operating a stereo camera on a South African icebreaker SA Agulhas II During their 2017 Antarctic expedition, they captured valuable insights into the behavior of waves in this remote region.
Their method, which mimics human vision through continuous imaging, allowed researchers to reconstruct the wavy ocean surface in three dimensions, providing unprecedented clarity into ocean wave dynamics. Ta.
The first scientific measurement of a rogue wave was the 25.6 m Draupner wave recorded in the North Sea in 1995. Since the beginning of the 21st century, 16 cases of suspected rogue waves have been reported to him.
“Scientists have long theorized that Antarctica’s rough seas and fierce winds can cause large waves to ‘self-amplify’, resulting in rogue wave frequencies. “However, this has not yet been tested underwater,” Professor Toffoli said.
The team’s observations, using numerical and laboratory studies that suggested the role of wind in the formation of rogue waves, provided validation of these theories in a real marine environment.
“Our observations show that unique sea conditions with rough waves occur during the ‘young’ stage of the waves, when they are most susceptible to wind effects. This suggests that wind parameters are the missing link,” Professor Toffoli said.
“Wind creates a chaotic situation where waves of different dimensions and directions coexist.”
“The wind causes young waves to grow higher, longer and faster.”
“During this self-amplification, waves grow disproportionately at the expense of neighboring waves.”
“We show that young waves are showing signs of self-amplification and are likely to be wind-driven.”
“Once every six hours, we recorded waves that were twice as high as nearby waves.”
“This reflects laboratory models. The theory is that sea conditions are more likely to self-amplify, creating more rogue waves.”
“In contrast, no rough waves were detected in mature oceans that are not influenced by winds.”
The authors highlight the critical importance of integrating wind dynamics into predictive models for rough sea prediction.
“This shows that scientists need to take wind into account thoroughly when developing tools to predict rogue waves,” Professor Toffoli said.
of findings It was published in the magazine physical review letter.
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A. Toffoli other. 2024. Observation of the bad waters of the Southern Ocean. Physics.pastor rhett 132 (15): 154101; doi: 10.1103/PhysRevLett.132.154101
Source: www.sci.news
