Rogue waves, often described as ‘freak waves,’ are massive and unpredictable oceanic phenomena that can pose significant threats to maritime safety and coastal infrastructure. Historically, the unpredictability of rogue waves has made them a source of concern for sailors and oceanographers alike, as there was no reliable method to forecast their occurrence. In July 2024, artificial intelligence has opened new avenues for predicting these dangerous waves as researchers at the University of Maryland, Thomas Breunung and Balakumar Balachandran, have developed an AI system capable of analysing vast amounts of data from a network of 172 ocean buoys. This approach allows for the identification of wave patterns that precede rogue waves, providing crucial advance warnings of up to five minutes. This innovation not only enhances maritime safety but also represents a significant leap in our understanding of ocean dynamics.
About Rogue Waves
Rogue waves are unpredictable and rare waves that are exceptionally large in size in comparison to the other surrounding waves. Surprisingly, their height is double the maximum height of the surrounding waves that occur in a particular sea state. They are highly dangerous to the ships sailing in the oceans, infrastructure located at coasts and offshore (like lighthouses) along with human beings. Thus, maritime activities are at high risk due to rogue waves.
Background
As per Captain Jules Dumont d’Urville, a French scientist, the earliest known rogue wave occurred in 1826. It was recorded that the rogue waves with a massive height of 33m appeared in the Indian Ocean.
Later, in 1995, a rogue wave named the Draupner Wave or New Year’s Wave occurred in the North Sea. For the first time, a measuring instrument was used to identify this rogue wave.
At times, rogue waves are found in the Agulhas and the Gulf Stream current.
In November 2020, a rogue wave with a height of 45 metres appeared in the waters along the Amphitrite Bank in the Pacific Ocean.
Contrary to typical waves, rogue waves appear randomly at any time, without warning, and from any direction, barring the direction of the prevailing wind and waves. It has been reported that these extreme storm waves seem to be the ‘walls of water’. They have highly steep sides and exceptionally deep troughs. They are known by different names, including monster waves, killer waves, freak waves, episodic waves, abnormal waves, and extreme storm waves. They are extremely dangerous, as the average sea state conditions are resisted by them. Their size is twice that of the surrounding waves.
Sea State
In the field of oceanography, the sea state is the general condition of the surface of a huge water body, like sea or ocean, at a given point of time and location. It is usually characterised by the period, height and power of waves. The sea state code of the World Meteorological Organization (WMO) distinguishes sea state on the basis of wave height. This wave height is measured on a scale of 0 to 9. ‘0’ refers to the absence of waves, while ‘9’ refers to the waves having a height of more than 14 metres.
Formation of Rogue Waves
As per the National Oceanic and Atmospheric Administration (NOAA) of the USA, rogue waves can be formed owing to any of the following events:
- Distant weather systems, rather than local winds, may result in swells. When these swells join together, a single, enlarged wave is formed, known as rogue wave. This event is called swells converge.
- When swells are compressed by ocean currents, powerful billows are developed, which in turn lead to rogue waves.
- Another climatic event, known as constructive interference, also causes the formation of rogue waves. Upon meeting of the two or more waves, their crests, troughs as well as lengths get aligned with each other. This in turn increases the wave height, making it the towering wave. Such a wave may remain only for a few minutes. The waves in this climatic event are usually the ones produced from different sources, like wind and currents. This event may also include the waves that travel long distances and their wavelengths gradually turn similar.
- Besides, rogue waves are also formed if an obstacle comes in the way of a huge wave. This obstacle may be a raised seabed or a reef.
In such a case, the wave gets retreated, thereby reflecting its energy back onto itself. This significantly increases the wave height, and thus, a massive steep wave rises high up in the sky. Such a wave cannot be easily tackled by a ship.
The crest of a wave is its highest point. The trough of the wave is its lowest point. The height of the wave is the amount of distance between these two points, i.e., the crest and the trough.
Use of AI Model to Predict Rogue Waves
The mathematicians, Breunung and Balachandran, carried out the research that took into account certain samples on wave patterns. These samples had the duration of 20 minutes each. Around 172 ocean buoys were considered to record these samples.
Researchers have made a remarkable advancement in predicting rogue waves with the help of AI. Using the afore-mentioned samples, they trained their AI program to detect specific wave patterns that appear just before the appearance of the rogue waves and examine them. The AI can differentiate them from usual wave patterns, as AI was made to compare the specific wave patterns with usual wave patterns.
As a result, it was discovered that around 75 per cent rogue waves could be predicted subsequently by the AI program one minute in advance. Approximately 73 per cent rogue waves could be predicted five minutes in advance. Further, it was found that the AI program was capable of predicting rogue waves at varied locations and depths near buoys. Thus, it can be applicable universally.
However, AI predictions can be made more accurate and can be achieved even earlier than the present advanced warning time with the help of integration of physical quantities. These quantities include wind speeds, water depths and buoy locations. The AI predictions can be as good as perfect in the future by employing modern AI architectures and gathering more data.
Challenges in Predicting Rogue Waves
Historically, it has been challenging to forecast rogue waves as they appear suddenly and rarely. Although the devastating effects of rogue waves are known, scientists all over the world had been clueless regarding the occurrence of the rogue waves until now. They faced challenges in predicting these waves due to the absence of appropriate methods. However, scientists inform that predicting rogue waves is not impossible. As a matter of fact, there are no real-time forecasting methods, which makes them unpredictable. This leads to devastating consequences, such as sinking of ships and overturning of ships, and human and property loss, as they can wash off crew into the ocean. Owing to the rogue waves, lighthouses and oil-drilling stations can also be damaged. As per the Catalogue of Rogue Waves, reported in mass media sources in 2011 and 2018, there were around 386 casualties along with the drowning of 24 ships due to rogue waves in the World Oceans.
Scientists are yet to invent a method for measuring and studying the rogue waves. They are still investigating the conditions when and how these waves are formed.
Conclusion
To conclude, rogue waves have historically resulted in numerous casualties and significant maritime disasters. However, the advancements in artificial intelligence have showcased its remarkable potential for universally predicting these formidable waves. By integrating additional data, such as water depth and wind speed, future enhancements to AI forecasting systems could further improve prediction accuracy. This breakthrough in rogue wave forecasting marks a significant leap forward in maritime safety, enabling timely warnings that can save lives and minimise damage. As research continues to evolve, the impact of AI on understanding and mitigating the risks associated with rogue waves is poised to grow even more substantial.
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