https://www.global.hokudai.ac.jp/blog/the-blast-that-shook-the-ionosphere/ Hokkaido University * Students + Japanese Language Courses + Newly Admitted Students + Academic Support + Career + Graduation & Departure + Academic Information (ELMS) + Syllabus Search + Library * Faculty & Staff + Career Path Support for PhD Students and Postdocs + Promotion office of Research environment for Diversity (Ree-D) + Internal Support Activities (URA) + KAKENHI Information + Hokkaido University Translated Information Archiving Database (HUTRIAD) + About Press Releases (internal-only) * Alumni & Supporters + Alumni Network - Registration + Hokudai Alumni Associations Across Japan and the World + Hokkaido University Ambassador and Partner System + Give * Maps + Sappporo Campus + Hakodate Campus + HU in Japan + HU in Global * Japanese Site * Contact Us Search [ ]Search Menu * ABOUT + From the President + University Profile + Discover Our History + Hokkaido Universal Campus Initiative (HUCI) + Brochures + Public Relations + Press Room + Social Media + E-Newsletter + Facilities + Access & Maps + Contribution to a Sustainable Society * RESEARCH AND EDUCATION + Undergraduate Schools + Graduate Schools + Research Institutes and Centers + Research Programs + Education Programs + Global Institution for Collaborative Research and Education (GI-CoRE) + Institute for Chemical Reaction Design and Discovery (ICReDD) + Spotlight on Research + Tackling Global Issues + COVID-19 Research + Resources for Researchers during the COVID-19 Pandemic + Open Courseware + Find an Academic Paper (HUSCAP) + Find a Researcher * ADMISSIONS + Why Hokkaido University? + Undergraduate Admissions + Graduate Admissions + Double Degree, Cotutelle & Joint Degree Programs + Exchange Student Admissions + Scholarships + Student Fees + Student Financial Aid + Visa * UNIVERSITY LIFE + Discover Campus Life + Discover Hokkaido + Housing + Arrive and Thrive + Safety + Health and Wellness + Sport and Recreation + Helpful Organizations * Global + Institute for International Collaboration + Overseas Satellite Offices + Overseas Partnerships + International Student Data + Outbound Programs + International Visits * Students + Japanese Language Courses + Newly Admitted Students + Academic Support + Career + Graduation & Departure + Academic Information (ELMS) + Syllabus Search + Library * Faculty & Staff + Career Path Support for PhD Students and Postdocs + Promotion office of Research environment for Diversity (Ree-D) + Internal Support Activities (URA) + KAKENHI Information + Hokkaido University Translated Information Archiving Database (HUTRIAD) + About Press Releases (internal-only) * Alumni & Supporters + Alumni Network - Registration + Hokudai Alumni Associations Across Japan and the World + Hokkaido University Ambassador and Partner System + Give * Maps + Sappporo Campus + Hakodate Campus + HU in Japan + HU in Global * Japanese Site * Contact Us * Share on Twitter * Share on Facebook * Share on Google * Register to rss * Share * Print * Delicious * LinkedIn * Google bookmarks * Digg * Facebook * Technorati * Yahoo bookmarks * Stumbleupon * Newsvine * Diigo The blast that shook the ionosphere Research Press Release | March 17, 2021 A 2020 explosion in Lebanon's port city of Beirut led to a southward-bound, high-velocity atmospheric wave that rivaled ones generated by volcanic eruptions. [P2061-Fig1] The epicenter in Beirut, before and after the explosion (Bhaskar Kundu, et al. Scientific Reports. February 2, 2021). Just after 6 p.m. local time (15.00 UTC) on August 4, 2020, more than 2,750 tons worth of unsafely stored ammonium nitrate exploded in Lebanon's port city of Beirut, killing around 200 people, making more than 300,000 temporarily homeless, and leaving a 140-metre-diameter crater in its wake. The blast is considered one of the most powerful non-nuclear, man-made explosions in human history. Now, calculations by Hokkaido University scientists in Japan have found that the atmospheric wave from the blast led to electron disturbances high in Earth's upper atmosphere. They published their findings in the journal Scientific Reports. The team of scientists, which included colleagues from the National Institute of Technology Rourkela in India, calculated changes in total electron content in Earth's ionosphere: the part of the atmosphere from around 50 to 965 kilometres in altitude. Natural events like extreme ultraviolet radiation and geomagnetic storms, and man-made activities like nuclear tests, can cause disturbances to the ionosphere's electron content. "We found that the blast generated a wave that travelled in the ionosphere in a southwards direction at a velocity of around 0.8 kilometres per second," says Hokkaido University Earth and Planetary scientist Kosuke Heki. This is similar to the speed of sound waves travelling through the ionosphere. The team calculated changes in ionospheric electron content by looking at differences in delays experienced by microwave signals transmitted by GPS satellites to their ground stations. Changes in electron content affect these signals as they pass through the ionosphere and must be regularly taken into consideration to accurately measure GPS positions. [P2061-Fig2] The ionospheric disturbance caused by an explosion can be detected by differential ionospheric delays of microwave signals of two carrier frequencies from global navigation satellite system (GNSS) satellites (Bhaskar Kundu, et al. Scientific Reports. February 2, 2021). The scientists also compared the magnitude of the ionospheric wave generated by the Beirut blast to similar waves following natural and anthropogenic events. They found that the wave generated by the Beirut blast was slightly larger than a wave generated by the 2004 eruption of Asama Volcano in central Japan, and comparable to ones that followed other recent eruptions on Japanese islands. The energy of the ionospheric wave generated by the Beirut blast was significantly larger than a more energetic explosion in a Wyoming coal mine in the USA in 1996. The Beirut blast was equivalent to an explosion of 1.1 kilotons of TNT, while the Wyoming explosion was equivalent to 1.5 kilotons of TNT. The total electron content disturbance of the Wyoming explosion was only 1/10 of that caused by the Beirut blast. The scientists believe this was partially due to the Wyoming mine being located in a somewhat protected pit. Original Article: Bhaskar Kundu et al. Atmospheric wave energy of the 2020 August 4 explosion in Beirut, Lebanon, from ionospheric disturbances. Scientific Reports. February 2, 2021. DOI: 10.1038/s41598-021-82355-5 Funding: This work was supported by a National Institute of Technology Rourkela (NITR) research fellowship and the Japan Society for the Promotion of Science (JSPS) KAKENHI (JP20K04120). Contacts: Professor Kosuke Heki Department of Earth and Planetary Science Hokkaido University E-mail: heki[at]sci.hokudai.ac.jp Sohail Keegan Pinto (International Public Relations Specialist) Public Relations Division Hokkaido University Tel: +81-11-706-2185 Skype: hokudai.pr1 Email: en-press[at]general.hokudai.ac.jp CATEGORY * All News * University News * Research News + Research Highlight + Research Press Release * Event * Awards + Research Awards + Student Awards LATEST NEWS University News | March 12, 2021 DEMOLA Hokkaido - Connecting students and enterprises through innovative collaborations University News | March 10, 2021 Indonesian Student Association of Hokkaido held their first international academic webinar University News | February 17, 2021 HOKKAIDO UNIVERSITY EMERGENCY BULLETIN BOARD now open: Stay informed during an emergency University News | February 01, 2021 Hokkaido Summer Institute 2021 application is now open University News | January 29, 2021 [NOTICE] Website temporary suspension due to maintenance on Feb. 5 ARCHIVES * 2021 * 2020 * 2019 * 2018 * 2017 * 2016 * 2015 * 2014 * 2013 * 2012 * Facebook * Twitter * Instagram * YouTube * LinkedIn BACK TO TOP * ABOUT + From the President + University Profile + Discover Our History + Hokkaido Universal Campus Initiative (HUCI) + Brochures + Public Relations + Press Room + Social Media + E-Newsletter + Facilities + Access & Maps + Contribution to a Sustainable Society * RESEARCH AND EDUCATION + Undergraduate Schools + Graduate Schools + Research Institutes and Centers + Research Programs + Education Programs + Global Institution for Collaborative Research and Education (GI-CoRE) + Institute for Chemical Reaction Design and Discovery (ICReDD) + Spotlight on Research + Tackling Global Issues + COVID-19 Research + Resources for Researchers during the COVID-19 Pandemic + Open Courseware + Find an Academic Paper (HUSCAP) + Find a Researcher * ADMISSIONS + Why Hokkaido University? + Undergraduate Admissions + Graduate Admissions + Double Degree, Cotutelle & Joint Degree Programs + Exchange Student Admissions + Scholarships + Student Fees + Student Financial Aid + Visa * UNIVERSITY LIFE + Discover Campus Life + Discover Hokkaido + Housing + Arrive and Thrive + Safety + Health and Wellness + Sport and Recreation + Helpful Organizations * Global + Institute for International Collaboration + Overseas Satellite Offices + Overseas Partnerships + International Student Data + Outbound Programs + International Visits * Site Policy * Site Map * Contact Us * Jobs * Media Inquiries * Emergency Contacts Hokkaido University Kita 8, Nishi 5, Kita-ku, Sapporo, Hokkaido, 060-0808 Japan +81-11-716-2111 Hokkaido University (c) Hokkaido University