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@PhDThesis{Jonah:2017:ObSi,
               author = "Jonah, Olusegun Folarin",
                title = "A study of daytime MSTIDs over equatorial and low latitude regions 
                         during tropospheric convection: observations and simulations",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-02-17",
             keywords = "TEC, daytime MSTIDs generation mechanisms, AGW activities, 
                         convective weather activities, daytime MSTIDs geomagnetic 
                         conjugate mappings, mecanismos de gera{\c{c}}{\~a}o de MSTIDs 
                         diurnos, AGW atividade, atividade climat{\'e}rica convectiva, 
                         mapeamento do conjugado geomagn{\'e}tico MSTIDs diurno.",
             abstract = "Medium Scale Travelling Ionospheric Disturbances (MSTIDs) are the 
                         highly dynamical phenomenona covering all latitudes in the F 
                         region ionosphere and they propagate a long distance, often in the 
                         form of wave-fronts. Their presence in a wide region pose threat 
                         to the radio propagation and trigger the equatorial plasma bubble 
                         which disrupts the GNSS navigation system. Atmospheric Gravity 
                         Wave (AGW) is believed to be the cause of these MSTIDs during 
                         daytime. However, the seeding mechanism of these AGWs is still a 
                         research question. The objective of this thesis is to study the 
                         dynamics of daytime MSTIDs over Brazil using detrended TEC, with 
                         focus on understanding their propagation characteristics. In 
                         addition, this thesis also presents novel results on daytime 
                         MSTIDs geomagnetic conjugate mapping characteristics and 
                         mechanisms responsible. Both observational and theoretical tools 
                         are employed to pursue these objectives. Observational data 
                         obtained using instruments such as a network of GNSS receivers, 
                         digisonde, low-orbiting satellites (COSMIC) and meteorological 
                         satellites (GOES Satellite) are analyzed to identify the driving 
                         source of MSTIDs-AGW. Interesting characteristics associated with 
                         the widely pursued convective-AGWs driven generation mechanism 
                         from past literatures, are investigated. This mechanism is further 
                         studied theoretically, by adapting a 
                         Convectional-Atmosphere-Ionosphere-Coupled model (CAI-CM) to 
                         incorporate the dynamics of convectively generated AGWs and their 
                         coupling to the ionosphere. The numerical simulation work also 
                         utilizes the SAMI3 (Sami3 is Another Model of the Ionosphere) 
                         model to capture the fundamental physics of the ionosphere. The 
                         SAMI3 model is used to simulate a large region of the ionosphere 
                         for the self-consistent development of MSTIDs. Finally the 
                         simulated MSTIDs from both CAI-CM and SAMI3 model are compared 
                         with the observed MSTIDs. RESUMO: Os Dist{\'u}rbios 
                         ionosf{\'e}ricos propagantes de m{\'e}dia escala (MSTIDs) 
                         s{\~a}o fen{\^o}menos altamente din{\^a}micos que cobrem todas 
                         as latitudes na ionosfera da regi{\~a}o F e propagam uma longa 
                         dist{\^a}ncia, geralmente sob a forma de frentes de onda. Suas 
                         presen{\c{c}}as em uma regi{\~a}o ampla afetam a 
                         propaga{\c{c}}{\~a}o de r{\'a}dio e podem gerar a bolha de 
                         plasma equatorial, a qual por sua vez pode interromper o sistema 
                         de navega{\c{c}}{\~a}o GNSS. Acredita-se que a Onda de Gravidade 
                         Atmosf{\'e}rica (AGW) seja a causa destes MSTIDs durante o dia. 
                         No entanto, o mecanismo de gera{\c{c}}{\~a}o destas AGWs ainda 
                         {\'e} uma quest{\~a}o de pesquisa. O objetivo desta tese {\'e} 
                         estudar a din{\^a}mica das MSTIDs diurnas sobre o Brasil 
                         utilizando TEC ap{\'o}s a remoc{\~a}o da tend{\^e}ncia, com 
                         foco na compreens{\~a}o de suas caracter{\'{\i}}sticas de 
                         propaga{\c{c}}{\~a}o. Al{\'e}m disso, esta tese tamb{\'e}m 
                         apresenta novos resultados sobre as caracter{\'{\i}}sticas de 
                         mapeamento do conjugado geomagn{\'e}tico do MSTID diurno e os 
                         mecanismos respons{\'a}veis. Ambos instrumentos observacionais e 
                         te{\'o}ricos s{\~a}o empregados para atingir esses objetivos. Os 
                         dados observacionais obtidos usando instrumentos como uma rede de 
                         receptores GNSS, digissonda, sat{\'e}lites de baixa {\'o}rbita 
                         (COSMIC) e sat{\'e}lites meteorol{\'o}gicos (GOES) s{\~a}o 
                         analisados para identificar os mecanismos de gera{\c{c}}{\~a}o 
                         das MSTIDs-AGW. S{\~a}o investigadas caracter{\'{\i}}sticas 
                         interessantes associadas ao mecanismo de gera{\c{c}}{\~a}o por 
                         AGWs convectivas amplamente persquisadas em literaturas passadas. 
                         Este mecanismo {\'e} ainda estudado teoricamente, adaptando um 
                         modelo Convectional-Atmosphere- Ionosphere-Coupled (CAI-CM) para 
                         incorporar a din{\^a}mica de AGWs convectivamente geradas e seu 
                         acoplamento com a ionosfera. O trabalho de simula{\c{c}}{\~a}o 
                         num{\'e}rica tamb{\'e}m utiliza o modelo SAMI3 (Sami3 {\'e} 
                         Outro Modelo da Ionosfera) para capturar a f{\'{\i}}sica 
                         fundamental da ionosfera. O modelo SAMI3 {\'e} usado para simular 
                         uma grande regi{\~a}o da ionosfera para o desenvolvimento 
                         auto-consistente de MSTIDs. Finalmente, as MSTIDs simuladas do 
                         modelo CAI-CM e SAMI3 s{\~a}o comparadas com as MSTIDs 
                         observadas.",
            committee = "Alves, Maria Virginia (presidente) and Paula, Eurico Rodrigues de 
                         (orientador) and Kherani, Esfhan Alam (orientador) and Pimenta, 
                         Alexandre Alvares and Valladares, Cesar and Oliveira, 
                         Virg{\'{\i}}nia Klausner de",
           copyholder = "SID/SCD",
         englishtitle = "Um estudo de MSTIDs do dia por regi{\~o}es equatoriais e baixa 
                         latitude durante a convec{\c{c}}{\~a}o troposf{\'e}rica: 
                         observa{\c{c}}{\~o}es e simula{\c{c}}{\~o}es",
             language = "en",
                pages = "187",
                  ibi = "8JMKD3MGP3W34P/3NAAB2L",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3NAAB2L",
           targetfile = "publicacao.pdf",
        urlaccessdate = "29 nov. 2020"
}


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