The eruption of Hunga Tonga results in a data explosion
The eruption of the huge South Pacific Hunga submarine volcano on January 15, 2022 devastated the island nation of Tonga, creating a variety of atmospheric wave types, including a boom heard 6,200 miles (10,000 km) away in Alaska. rice field. It also created an atmospheric pulse that caused anomalous tsunami-like disturbances that arrived on the Pacific coast earlier than the actual tsunami.
These are one of many observations reported by a team of 76 scientists from 17 countries who have studied the atmospheric waves of the largest eruption known from volcanoes since the 1883 eruption of Krakatoa.The work of the team, edited in an unusually short time due to significant scientific interest in the eruption, was published in the journal on May 12, 2022. Chemistry..
David Fee, director of the Wilson Alaska Technical Center at the University of Alaska Fairbanks Institute for Geophysics, is the lead author of the research paper and one of the four scientists at the center involved in the research.
The Hunga eruption near Tonga provided unprecedented insight into the behavior of some atmospheric waves. A dense network of Alaska barometers, ultra-low frequency sound sensors, and seismographs operated by the Wilson Alaska Technical Center of the Institute of Geophysics, the Alaska Volcano Observatory, and the Alaska Seismic Center contributed to the data.
“Our hope is that understanding the atmospheric waves from this eruption will allow us to better monitor volcanic eruptions and tsunamis,” said Fee, who is also a coordinating scientist. At the Geophysical Institute of the Alaska Volcano Observatory.
“Atmospheric waves were recorded globally over a wide frequency band. Studying this remarkable data set will give us a better understanding of the generation, propagation and recording of acoustic and atmospheric waves,” he said. Said. “This affects the monitoring of nuclear explosions, volcanoes, earthquakes, and various other phenomena.”
Researchers have found that the behavior of eruptive Lamb waves is particularly interesting. This type is named after the British mathematician Horeslam, who was the discoverer in 1917.
Largest atmospheric explosions, such as volcanic eruptions and nuclear tests, generate Lamb waves. They can last from minutes to hours.
Lamb waves are a type of guided wave that propagate parallel to the surface of the material and extend upward. In the Hunga eruption, the waves traveled along the surface of the Earth, orbiting the planet four times in one direction and three times in the opposite direction. This is the same as that observed during the 1883 eruption of Krakatau.
“Lamb waves are rare, and there are few high-quality observations of them,” says Fee. “Understanding Lamb waves gives us a better understanding of sources and eruptions. This is related to the occurrence of tsunamis and volcanic eruptions, as well as the high frequency ultra-low frequency sounds and sound waves from eruptions. It may be related. “
The Lamb wave consisted of at least two pulses near Hunga, with the first pulse increasing the pressure for 7-10 minutes, followed by the second and subsequent compressions followed by a long pressure decrease.
According to data from ground-based observatories, the waves also reached the Earth’s ionosphere, climbing to an altitude of about 280 mph at 700 mph.
According to the paper, the main difference from the Hanga explosion Lamb wave compared to the 1883 wave is the amount of data collected by technological advances over a century and the proliferation of sensors around the world.
Scientists have noted other discoveries about eruption-related atmospheric waves, including “significant” long-range infrasound — sounds too low for humans to hear. Infrasound arrived after Lamb waves, followed by audible sounds in some areas.
The audible sound, a paper memo, traveled about 6,200 miles to Alaska and was heard throughout the state as a recurring boom about nine hours after the eruption.
“I heard the sound, but I didn’t think it was due to a volcanic eruption in the South Pacific at the time,” Fee said.
The Alaska report is the farthest documented description of the audible sound from that source. The paper states that this is partly due to the growing population of the world and the advancement of social connections.
“We will study these signals over the years and learn how atmospheric waves are generated and how well they propagate throughout the globe,” says Fee.
Reference: “Hunga Tonga in January 2022” by Robin S. Matza, David Fee, Jere D. Asink, Alexandra M. Yezi, David N. Green, Kiwamu Kim, Liam Tony, Thomas Lecock Tonga Atmospheric Waves and Global Seismic Sound Observations ”, Siddharth Krishnamoorthy, Jean-Marie Lalande, Kiwamu Nishida, Kent L. Gee, Matthew M. Haney, Hugo D. Ortiz, Quentin Brissaud, LéoMartire, Lucie Rolland, Panagiotis Vergados Alexandra Nippress, Junghyun Park, Shahar Shani-Kadm Alex Witsil, Stephen Arrowsmith, Corentin Caudron, Shingo Watada, Anna B. Perttu, Benoit Taisne, Pierrick Mialle, Alexis Le Pichon, Julien Vergoz, Patrick Hupe, Philip S. Blom, Roger Wax , Silvio De Angelis, Jonathan B. Snively, Adam T. Ringler, Robert E. Anthony, Arthur D. Jolly, Geoff Kilgour, Gil Averbuch, Maurizio Ripepe, Mie Ichihara, Alejandra Arciniega-Ceballos, Elvira Astafyeva, Lars Ceranna, Sandrine , Il-Young Che, Rodrigo De Negri, Carl W. Ebeling, Läslo G. Evers, Luis E. Franco-Marin, Thomas B. Gabrielson, Katrin Hafner, R. Giles Harrison, Attila Komjathy, Giorgio Lacanna, John Lyons, Kenneth A. Macpherson, Emanuele Marchetti, Kathleen F. McKee, Robert J. Mellors, Gerardo Mendo-Pérez, T. Dylan Mikesell, Edhah Munaibari, Mayra Oyola -Merced, Iseul Park, Christoph Pilger, Cristina Ramos, Mario C. Ruiz, Roberto Sabatini, Hans F. Schwaiger, Dorianne Tailpied, Carrick Talmadge, Jérôme Vidot, Jeremy Webster, David C May 12, 2014, Science.
DOI: 10.1126 / science.abo7063
Other geophysical laboratories involved in the study include graduate student Liam Tony, sound analysis, and the production of diagrams and animations. Postdoctoral Fellow Alex Witsil, Sonic Analysis and Equivalent Explosive Yield Analysis. Seismic acoustics researcher Kenneth A. McPherson, sensor response and data quality. All located at the Wilson Alaska Technical Center.
The Alaska Volcano Observatory, the National Science Foundation, and the Defense Threat Reduction Agency have funded the UAF portion of the study.
Robin S. Matoza of the University of California, Santa Barbara is the lead author of this paper.