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Giovanni Ninto Occhipinti, Associate Profesor at the Institut de Physique du Globe de Paris (U. Denis Diderot) presents “No Magnitude, No Glory: The recent history of Ionospheric Seismology from Sumatra 2004 to Chile 2015 through the revolutionary observations of Tohoku-Oki 2011”.
“Detection of ionospheric anomalies following the Sumatra and Tohoku earthquakes (e.g., Occhipinti et al. 2006, 2010, 2011, 2013) demonstrated that ionosphere is sensitive to earthquake and tsunami propagation: ground and oceanic vertical displacement induces acoustic-gravity waves propagating within the neutral atmosphere and detectable in the ionosphere. Observations supported by modelling proved that ionospheric anomalies related to tsunamis and Rayleigh waves are deterministic and reproducible by numerical modeling via the ocean/neutral-atmosphere/ionosphere coupling mechanism (Occhipinti et al., 2008, 2010). Ionospheric observations, compared with classic seismometers, consistent with the propagation of Rayleigh waves related to 38 events, with a magnitude larger than 6.2, is showed here to prove that “ionospheric seismometers” are useful seismological data to estimated magnitude and better cover the Earth. Concerning tsunamis, to prove that the their signature in the ionosphere is routinely detected we show here perturbations of total electron content (TEC) measured by GPS and following tsunamigenic earthquakes from 2004 to 2011 (Rolland, Occhipinti et al. 2010, Occhipinti et al., 2013), nominally, Sumatra (26 December, 2004 and 12 September, 2007), Chile (14 November, 2007), Samoa (29 September, 2009) and the recent Tohoku-Oki (11 Mars, 2011). Based on the observations close to the epicenter, mainly performed by GPS networks located in Sumatra, Chile and Japan, we highlight the TEC perturbation observed within the first hour after the seismic rupture. This perturbation contains information about the ground displacement, as well as the consequent sea surface displacement resulting in the tsunami. In addition to GPS-TEC observations close to the epicenter and measured by GEONET network, new exciting measurements in the far-field were performed by Airglow measurement in Hawaii: those measurements show the propagation of the IGWs induced by the Tohoku tsunami in the Pacific Ocean (Occhipinti et al., 2011). This revolutionary imaging technique is today supported by two new observations of moderate tsunamis: Queen Charlotte (M: 7.7, 27 October, 2013) and Chile (M: 8.2, 16 September 2015). The potential idea to put an Airglow camera on a satellite opens new exciting perspectives for tsunami detection. In this talk we present all this new earthquake and tsunami observations in the ionosphere and we discuss, under the light of modelling, the potential role of ionospheric sounding in magnitude estimation, oceanic monitoring and future tsunami warning system.”
Giovanni Occhipinti, aka Ninto, graduated at the Università di Bologna, Italy, than he received his PhD at the Institut de Physique du Globe de Paris and the Office National d’Etudes et Recherches Aérospatiales. After post-doctorate studies at the Jet Propulsion Laboratory (NASA) and Seismological Laboratory (Caltech), he returned to France as faculty at the Paris Diderot University. He currently maintains his research at the Institut de Physique du Globe de Paris and strongly collaborates with several institutes worldwide (ONERA, JPL, ETH, ERI, EOS, etc). Ninto consecrated his research to the detection and modeling of Earthquake and Tsunami by ionospheric sounding, as well as studies about ionospheric background based on tomographic methods. In 2016 he became a junior member of the Institut Universitaire de France.