@InProceedings{FigueiredoVaBeBoTaWr:2022:SeGrWa,
               author = "Figueiredo, Cosme Alexandre Oliveira Barros and Vadas, Sharon and 
                         Becker, Erich and Bossert, Katrina and Takahashi, Hisao and 
                         Wrasse, Cristiano Max",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {NorthWest 
                         Research Associates} and {NorthWest Research Associates} and 
                         {Arizona State University} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)}",
                title = "Secondary Gravity Waves Generated by the Tonga Volcano Explosion 
                         and Its Effect on the New Zealand, Australia, and South America 
                         Ionosphere",
                 year = "2022",
         organization = "AGU Fall Meeting",
            publisher = "AGU",
             abstract = "In this presentation, we discuss the Traveling ionospheric 
                         disturbances observed over New Zealand, Australia, and South 
                         America that were caused by the multiple explosions of the Tonga 
                         volcano (20° S; 175° W) on January 15, 2015, the first one of 
                         which occurred at ~4:15 UT. To observe the ionospheric effects at 
                         these locations, approximately 1000 GNSS receivers were used to 
                         calculate the detrended total electronic content (dTEC). 
                         Approximately 1.0 - 1.5 hour after the first explosion, traveling 
                         ionospheric disturbances (TIDs) were observed over New Zealand 
                         with a horizontal wavelength (\λ_H) of 1300-1525 km, 
                         horizontal phase velocity (C_H) of 551-635 m/s, period (\τ) 
                         of 39-40 min, and azimuth (?) (\α) of 210-215°. On the other 
                         hand, in Australia, TIDs were observed 3 hours after the explosion 
                         with \λ_H, C_H, \τ, and \α of 861 km, 478 m/s, 
                         30 min, and 266°, respectively. Finally, in South America, 8 hours 
                         after the explosion, we observed TIDs with the following 
                         characteristics: \λ_H between 348 and 1174 km, C_H of 294 - 
                         515 m/s, \τ of 19 - 36 min., and \α of 32°. Between 
                         18:00 UT and 19:00 UT, we also observed TIDs over South America 
                         with \λ_H of 330-505 km, C_H of 275 - 350 m/s, \τ of 
                         20 - 24 min., and \α of 32-139°. We then discuss using the 
                         Model for gravity wavE SOurce, Ray trAcing and reConstruction 
                         (MESORAC) to calculate the primary GWs and the HIAMCM (HI Altitude 
                         Mechanistic general Circulation Model) model to determine the 
                         secondary GWs in the thermosphere created by these explosions. Via 
                         comparison with these model results, we show that it is the 
                         secondary GWs which propagate over New Zealand, Australia, and 
                         South America.",
  conference-location = "Chicago, IL",
      conference-year = "12-16 Dec. 2022",
        urlaccessdate = "11 maio 2024"
}