Scince Alert September 25, 2022 Recently, researchers calculated that the eruption of Hunga Tonga-Hunga Ha’apa spewed a staggering 50 million tons of water vapor into the atmosphere, in addition to enormous quantities of ash and volcanic gases. Particles of rock and ash can also temporarily cool the planet by blocking sunlight. Widespread and violent volcanic activity in Earth’s distant past may have contributed to global climate change, triggering mass extinctions millions of years ago. In underwater volcanoes, submarine eruptions can draw large parts of their explosive energy from the interaction of water and hot magma, which propels huge quantities of […]
Category Archives: Volcanoes
Tonga is home to 170 islands. A new one just formed from an underwater volcanic eruption
Phys.org September 27, 2022 The Pacific nation of Tonga is made up of 170 islands, but it just welcomed its newest addition—thanks to an underwater volcano. Near the center of the nation’s island formation lies the Home Reef volcano in the South Pacific. On Sept. 10, the volcano began to erupt for the first known time since 2006, oozing lava and ejecting plumes of steam and ash in and above water, according to NASA’s Earth Observatory. Just 11 hours after the eruption began, a new island had appeared, and NASA confirmed its formation with satellite images. When the island was […]
Elusive atmospheric wave detected during Tonga volcanic eruption
Phys.org September 19, 2022 Using state-of-the-art observational data and computer simulations an international team of researchers (Japan, USA -University of Hawaii) discovered the existence of Pekeris waves—fluctuations in air pressure that were theorized in 1937 but never proven to occur in nature, till after the Tonga eruption. The atmospheric wave pattern close to the eruption was quite complicated, but thousands of miles away the disturbances were led by an isolated wave front traveling horizontally at more than 650 miles per hour as it spread outward. The air pressure perturbations associated with the initial wave front were seen clearly on thousands […]
The World Is Not Ready For The Next Super-Eruption, Scientists Warn
Science Alert September 6, 2022 According to researchers in the UK over the next century, large-scale volcanic eruptions are hundreds of times more likely to occur than are asteroid and comet impacts, put together. The peril posed by volcanoes may also be greater. In a 2021 study based on data from ancient ice cores, researchers found the intervals between catastrophic eruptions are hundreds or even thousands of years shorter than previously believed. The history of many volcanoes remains murky, making it hard to anticipate future eruptions and focus resources where risks are highest. According to the researchers we need more […]
Shockwave caused by Tonga underwater eruption may help scientists predict future tsunamis
Phys.org July 14, 2022 Researchers in Japan believe that it may be possible to predict tsunamis faster by tracking the atmospheric disturbances caused by the airwaves they create and the errors in the positional information supplied by GPS satellites. Examining the errors following eruption they found that it caused waves of air pressure to spread as far as Australia and Japan. These waves oscillated the lower part of the ionosphere and generated an electric field that was then transmitted at high speed to the upper ionosphere. They detected the electron changes much earlier than the air pressure waves that caused […]
Tonga Volcano Blasted Out Pressure Waves “Very Close to The Theoretical Limit”
Science Alert July 1, 2022 The initial explosion and subsequent plume triggered atmospheric waves which propagated around the world multiple times. An international team of researchers (UK, USA – industry, University of Massachusetts Lowell, Virginia Tech, University of Colorado Boulder, NASA Goddard Space Flight Center, Catholic University of America, Germany, Australia, France) show the details of this response, using a comprehensive set of satellite and ground-based observations to quantify it from surface to ionosphere. A broad spectrum of waves was triggered by the initial explosion, including Lamb waves propagating at phase speeds of 318.2±6 ms-1 at surface level and between […]
Scientists provide explanation for exceptional Tonga tsunami
Phys.org June 13, 2022 The colossal eruption of the Hunga Tonga-Hunga Ha’apai volcano and ensuing tsunami is the first global volcano-triggered tsunami recorded by modern, worldwide dense instrumentation, thus providing a unique opportunity to investigate the role of air-water coupling processes in tsunami generation and propagation. An international team of researcher (Portugal, UK, USA – Columbia University, Spain) used sea-level, atmospheric and satellite data from across the globe, along with numerical and analytical models, to demonstrate that this tsunami was driven by a constantly moving source in which the acoustic-gravity waves radiating from the eruption excite the ocean and transfer […]
Satellite mission finds that Tonga volcanic eruption effects reached space
Phys.org May 10, 2022 Analyzing data from NASA’s Ionospheric Connection Explorer (ICON) mission and ESA’s Swarm satellites, an international team of researchers (USA – UC Berkeley, University of Colorado, Germany) found that in the hours after the eruption, hurricane-speed winds and unusual electric currents formed in the ionosphere. Upon reaching the ionosphere and the edge of space, ICON clocked the windspeeds at up to 450 mph. After the eruption, the equatorial electrojet surged to five times its normal peak power and dramatically flipped direction, flowing westward for a short period. According to the researchers this is something we’ve only previously […]
New method for detecting pre-eruption warning signals at Whakaari White Island and other active volcanoes
Phys.org April 20, 2022 Even with real-time geophysical monitoring, forecasting sudden eruptions is difficult, because their precursors are hard to recognize and can vary between volcanoes. An international team of researchers (New Zealand, Belgium) has described a general seismic precursor signal for gas-driven eruptions, identified through correlation analysis of 18 well-recorded eruptions in New Zealand, Alaska, and Kamchatka. The precursor manifested in the displacement seismic amplitude ratio between medium (4.5–8 Hz) and high (8–16 Hz) frequency tremor bands, exhibited a characteristic rise in the days prior to eruptions. They interpreted this as formation of a hydrothermal seal that enables rapid pressurization of […]
Tonga Islands: A seismic algorithm reveals the magnitude of the January 2022 eruption
Phys.org April 20, 2022 By analyzing the seismic waves researchers in France were able to design an algorithm that can detect and locate a volcanic eruption in near real-time and, using equations that describe explosive eruptions, assess its size. Until now, such an assessment required field work and took several weeks or months, since it was necessary to estimate the volume of ash and lava produced. The authors show that the Hunga Tonga eruption ejected a volume of around 10 km3, making it the largest explosive eruption of the twenty-first century, equivalent in strength to that of the devastating eruption […]