Tyler O'Neal, Staff Editor SYSTEMS

How can the new model developed by Japanese scientists help improve tsunami warning systems?

Unlocking the secrets of the sea: How Japanese scientists are working to improve tsunami warning systems

The Hunga Tonga-Hunga Ha'apai volcano in Tonga erupted on January 15, 2022, causing massive amounts of energy to be released into the atmosphere and ocean, leading to tsunamis across the Pacific Ocean. The Shocks, Solitons, and Turbulence Unit of the Okinawa Institute of Science and Technology (OIST) in Japan has conducted research into the disturbances in the atmosphere and ocean during this event and has developed a supercomputer model to enhance the current tsunami early warning systems.

Stephen Winn, a research technician in the unit and first author of the research article, stated “It's important to know how the atmospheric wave changes in time to make accurate predictions that would be of use for warning systems.”    

Unlike a regular tsunami caused by a rapid movement of the seabed, the large waves caused by the Tonga explosion were also influenced by a pressure wave hundreds of kilometers wide released into the atmosphere. The atmospheric pressure wave first moved upwards and then spread outwards traveling at 1,141 km/h on average, about 400km/h faster than a regular tsunami can travel in deep water. It traveled around the earth causing waves as far away as the Mediterranean Sea. “This was the first event of its kind recorded in detail by modern instruments,” Prof. Emile Touber, leader of the Shocks, Solitons and Turbulence Unit stated. 

As the atmospheric wave travels above the ocean, it displaces the body of water underneath, creating waves that travel faster than a regular tsunami. “Normally, a tsunami wave created in the Pacific would not reach the Mediterranean because it would have to travel around land masses to get there, but atmospheric waves are not restricted, traveling over those land masses,” Dr. Adel Sarmiento, a postdoc researcher at the unit explained. This is why the wave can reach worldwide and has a broader impact than a regular tsunami.  

The scientists used measurements from the Tonga event to validate their model and used a state-of-the-art code, dNami, co-developed by Dr. Nicolas Alferez at the Conservatoire National des Arts et Métiers in Paris, France, to rapidly simulate the earth during the event using the supercomputer at OIST. The code allows them to create simulations in satisfactory resolution, faster than real-time, so that they are useful for improving warning systems in the future.

Prof. Touber explained that they can now more accurately predict the arrival time and height of a wave at a specific location and rapidly identify areas at high risk. 

Hurricanes and typhoons can also cause disturbances in the atmosphere that interact with the sea, causing significant water level changes that will affect coastlines. “With our model, we can explore what might happen to the water flow as it approaches the coast if the sea level changes by a certain amount with certain typical storm conditions,” Prof. Touber said. “This can help decide on the kind of coastal defense systems that should be put in place for storm-related surges.” 

A group of scientists from Japan conducted a study on the interactions between the ocean and atmosphere that occurred after the Tonga volcano eruption. The results of the study were very promising as they developed a model that has the potential to predict high-risk areas with great accuracy and improve the existing tsunami warning systems. This research is a major milestone in understanding the complex interplay between the ocean and atmosphere and has the potential to save many lives and properties in the future.

Università di Trento prof Passerini wins €8M grant for the revolution of human-centric AI systems

Tyler O'Neal, Staff Editor SYSTEMS

The new EU-funded project that will kick off in autumn 2023, with 21 partner organizations from 9 countries across Europe, is set to develop a new generation of human-centric AI systems and to strengthen the leadership of Europe in this area

Artificial Intelligence (AI) holds tremendous potential to enhance human decisions and avoid cognitive overload and bias in high-stakes scenarios. To date, however, the adoption of AI-based support systems has been minimal in settings such as hospitals, tribunals, and public administrations.

The EU recognizes the need to foster research and innovation in this field, and on 13 March, TANGO secured €8M to develop the theoretical foundations and the computational framework for synergistic human-machine decision-making, paving the way for the next generation of human-centric AI systems. The new EU-funded project that will kick off in autumn 2023, with 21 partner organizations from 9 countries across Europe, is set to strengthen the leadership of Europe in this area.

TANGO argues that for AI to fully develop its enormous potential in terms of positive impact on individuals, society, and the economy, we need to completely rethink how AI systems are conceived. People should feel they can trust the systems they interact with, in terms of the reliability of their predictions and decisions, the capacity of the systems to understand their needs, and guarantees that they are genuinely aiming at supporting them rather than some undisclosed third party. In other words, a symbiosis should be established between humans and machines, in which all parties are aligned in terms of values, goals, and beliefs, and support and complement each other to reach objectives beyond what each would be able to do by itself.

“It takes two to TANGO! Our perspective is that a deep mutual understanding between humans and machines is essential for the development of truly effective and innovative AI systems that can expand human reasoning and decision-making capabilities“ says the project coordinator Andrea Passerini.

The potential impact on individuals and society of the TANGO framework will be evaluated on a pool of real-world use cases of extremely high social impact, namely supporting women during pregnancy and postpartum, supporting surgical teams in intraoperative decision-making, supporting loan officers and applicants in credit lending decision processes, and helping public policymakers in designing incentives and allocating funds. The success of these case studies will foster the adoption of TANGO as the framework of reference for developing a new generation of synergistic AI systems and will strengthen the leadership of Europe in human-centric AI.

The Karl G. Jansky Very Large Array radio telescope consists of 27 giant telescope dishes (each 25 meters in diameter) in New Mexico. Image credit: Shutterstock.
The Karl G. Jansky Very Large Array radio telescope consists of 27 giant telescope dishes (each 25 meters in diameter) in New Mexico. Image credit: Shutterstock.

Oxford produces new insights into binary star systems

Tyler O'Neal, Staff Editor SYSTEMS

Researchers from the University of Oxford have contributed to a major international study that has captured a rare and fascinating space phenomenon. An artist’s impression of an X-ray binary star system. This shows the normal star in yellow/red, the disc of rotating matter, the neutron star sitting in its centre, and the ‘radio jet’ shooting out. Credit: Instituto de Astrofísica de Canarias

Scientists have long been intrigued by X-ray binary star systems, where two stars orbit around each other with one of the two stars being either a black hole or a neutron star. Both black holes and neutron stars are created in supernova explosions and are very dense – giving them a massive gravitational pull. This makes them capable of capturing the outer layers of the normal star that orbits around it in the binary system, seen as a rotating disc of matter (mimicking a whirlpool) around the black hole/neutron star.

According to theoretical calculations, these rotating discs should show a dynamic instability: about once an hour, the inner parts of the disc rapidly fall onto the black hole/neutron star, after which these inner regions re-fill and the process repeats. Up to now, this violent and extreme process had only been directly observed once, in a black hole binary system. For the first time, it has now been seen in a neutron star binary system, called Swift J1858.6-0814. This discovery demonstrates that this instability is a general property of these discs (and not caused by the presence of a black hole).

The phenomenon was captured by combining data from five ground-based and space-based telescopes, together encompassing multiple wavelengths. The scientific team, an international collaboration of astronomers led by the Instituto de Astrofísica de Canarias, formed ad-hoc when the neutron star system was first discovered in 2018. These telescopes include the Karl G. Jansky Very Large Array: one of the world’s most sensitive radio telescopes, located in New Mexico, consisting of 27 massive (25-meter diameter) telescope dishes.

Dr. Jakob van den Eijnden, from the University of Oxford’s Department of Physics, lead the analysis of the data from the Karl G. Jansky Very Large Array. He said: ‘Our observations of the radio wavelength data highlighted an important property of these instabilities. We found that when the whirlpool empties, some of the gas is shot into space in so-called "radio jets": narrow beams of gas shot out at speeds close to the speed of light." Dr Jakob van den Eijnden. Image credit: St Hilda’s College, University of Oxford.

"I think that the international collaboration and involvement of many early-career researchers is one of the most exciting aspects of this work. We analyzed a truly unique dataset, that was extremely challenging to collect because the gas capturing process is ‘transient’: it takes place for only a couple of months, unpredictably, before shutting off again," said Eijnden.

The brightness of these jets is observed to be variable, which is now explained by blobs of jet material being launched at these extreme speeds whenever the disc starts or finishes emptying (causing peaks in brightness). When the disc stabilizes, the jets cease and the brightness reduces. Drawing this conclusion was only possible by comparing the variability observed with telescopes across the electromagnetic spectrum — from radio to X-ray wavelengths — which simultaneously probes the behavior of the disc and the jet.

Dr van den Eijnden added: "This discovery, only the second example of these instabilities, also highlights the rarity of this behavior. Therefore, finding more examples across different types of binary systems is a first priority. Due to the transient nature of this process, it is unpredictable when we will get another chance. By then, we will need to be prepared to repeat our international observing efforts."