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@MastersThesis{Picanço:2019:DeAnÍn,
               author = "Pican{\c{c}}o, Giorgio Arlan da Silva",
                title = "Desenvolvimento e an{\'a}lise de um {\'{\i}}ndice 
                         ionosf{\'e}rico baseado em dados de Conte{\'u}do Eletr{\^o}nico 
                         Total",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2019",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2019-03-28",
             keywords = "Ionosfera terrestre, DIX, perturba{\c{c}}{\~o}es 
                         ionosf{\'e}ricas, tempestades geomagn{\'e}ticas, bolhas de 
                         plasma, Earth's ionosphere, DIX, ionospheric disturbances, 
                         geomagnetic storms, plasma bubbles.",
             abstract = "Neste trabalho, apresenta-se um estudo sobre o desenvolvimento e a 
                         an{\'a}lise de um {\'{\i}}ndice ionosf{\'e}rico baseado em 
                         dados de Conte{\'u}do Eletr{\^o}nico Total (TEC), denominado 
                         {\'{\i}}ndice local de perturba{\c{c}}{\~o}es 
                         ionosf{\'e}ricas (LDIX). Para auxiliar esta pesquisa, 
                         estudaram-se as perturba{\c{c}}{\~o}es ionosf{\'e}ricas 
                         observadas durante per{\'{\i}}odos geomagneticamente calmos e 
                         perturbados. Para isso, foram analisados dez per{\'{\i}}odos 
                         espec{\'{\i}}ficos do ano de 2015, sendo cinco para cada 
                         condi{\c{c}}{\~a}o geomagn{\'e}tica. O {\'{\i}}ndice LDIX foi 
                         calculado ao longo de todos esses per{\'{\i}}odos e os 
                         resultados obtidos foram comparados com diversos par{\^a}metros 
                         ionosf{\'e}ricos e magn{\'e}ticos conhecidos e consolidados na 
                         literatura, tais como o foF2, o hF e o \ΔH. Na an{\'a}lise 
                         comparativa, tamb{\'e}m foram utilizados os {\'{\i}}ndices 
                         geomagn{\'e}ticos Kp, AE e Dst, assim como outros par{\^a}metros 
                         dos ionogramas, mapas de TEC e o {\'{\i}}ndice ionosf{\'e}rico 
                         DIX. As varia{\c{c}}{\~o}es dos per{\'{\i}}odos 
                         geomagneticamente perturbados foram analisadas de acordo com os 
                         processos f{\'{\i}}sicos que ocorrem durante tempestades 
                         geomagn{\'e}ticas (e.g. penetra{\c{c}}{\~a}o de campos 
                         el{\'e}tricos, d{\'{\i}}namo perturbado). Adicionalmente, as 
                         varia{\c{c}}{\~o}es observadas durante os per{\'{\i}}odos 
                         geomagneticamente calmos foram analisadas de acordo com os 
                         processos ionosf{\'e}ricos de origem interna (e.g. bolhas de 
                         plasma, din{\^a}mica da atmosfera). No intuito de qualificar o 
                         resultado do novo {\'{\i}}ndice quanto {\`a} forma de 
                         c{\'a}lculo do TEC que leva ao LDIX, foi verificada a 
                         diferen{\c{c}}a entre os valores de LDIX calculados a partir do 
                         TEC obtido dos TECMAPs do Programa Embrace/INPE e o TEC obtido 
                         diretamente de dados de GNSS, sendo esta diferen{\c{c}}a 
                         m{\'e}dia estimada em ~7,8%. Essa an{\'a}lise revelou que 
                         n{\~a}o h{\'a} diverg{\^e}ncias significativas entre as formas 
                         de c{\'a}lculo do LDIX. Quanto aos demais resultados, 
                         verificou-se que os {\'{\i}}ndices LDIX e DIX apresentaram 
                         pequenas discrep{\^a}ncias pontuais na aus{\^e}ncia de 
                         varia{\c{c}}{\~o}es ionosf{\'e}ricas de grande amplitude. Outro 
                         ponto relevante observado foram as limita{\c{c}}{\~o}es que o 
                         {\'{\i}}ndice DIX apresentou quanto {\`a} detec{\c{c}}{\~a}o 
                         de perturba{\c{c}}{\~o}es ionosf{\'e}ricas de car{\'a}ter 
                         diurno. Em contrapartida, o {\'{\i}}ndice LDIX foi capaz de 
                         detectar tais perturba{\c{c}}{\~o}es, variando seu valor de 
                         forma gradativa. Verificou-se, ainda que o {\'{\i}}ndice DIX 
                         apresentou discord{\^a}ncias com rela{\c{c}}{\~a}o ao LDIX, 
                         indicando perturba{\c{c}}{\~o}es inexistentes no TEC. Essas 
                         varia{\c{c}}{\~o}es foram classificadas como falsos positivos 
                         nas an{\'a}lises deste trabalho. Adicionalmente, verificou-se uma 
                         forte rela{\c{c}}{\~a}o entre os processos f{\'{\i}}sicos 
                         observados no par{\^a}metro foF2 e as perturba{\c{c}}{\~o}es 
                         observadas no LDIX, o que constata a signific{\^a}ncia 
                         f{\'{\i}}sica do LDIX. Nesse contexto, o LDIX mostrou-se 
                         superior ao {\'{\i}}ndice DIX, visto que este n{\~a}o 
                         apresentou a mesma similaridade f{\'{\i}}sica com 
                         rela{\c{c}}{\~a}o ao par{\^a}metro foF2. Finalmente, 
                         verificou-se que o {\'{\i}}ndice LDIX {\'e} capaz de detectar 
                         as respostas ionosf{\'e}ricas da ocorr{\^e}ncia de campos 
                         el{\'e}tricos do tipo overshielding, campos el{\'e}tricos do 
                         d{\'{\i}}namo perturbado (DDEF) e de bolhas de plasma de forma 
                         localizada. ABSTRACT: The present manuscript presents a study of 
                         the development and the analysis of an ionospheric index based on 
                         Total Electron Content (TEC) data, named Local Disturbance 
                         Ionosphere indeX (LDIX). In order to support such development, 
                         ionospheric disturbances observed during geomagnetically quiet and 
                         disturbed periods were studied. Thus, ten periods on 2015 were 
                         selected and analyzed, five of them to each geomagnetic condition. 
                         Therefore, the LDIX was calculated during these periods and the 
                         results were compared with several ionospheric and magnetic known 
                         stablished parameters, such as foF2, h'F and \ΔH. In the 
                         comparative analysis, geomagnetic indices Kp, AE and Dst were also 
                         used, as well as others ionogram parameters, TEC maps and the DIX. 
                         The index variations during geomagnetically disturbed periods were 
                         analyzed according to the driving physical processes ruling during 
                         geomagnetic storms (e.g., electric field penetration, ionospheric 
                         disturbance dynamo). On the other hand, LDIX variations observed 
                         during the geomagnetically quiet periods were analyzed in terms of 
                         the ionospheric processes of internal origin (e.g., plasma 
                         bubbles, atmospheric dynamics). In order to qualify the results of 
                         the new ionospheric index as to the calculation of the TEC that 
                         leads to the LDIX, we also verified a difference of 7.8% between 
                         the values of LDIX calculated from the TEC as they are obtained 
                         from the TECMAPs of the Embrace/INPE Program and the TEC obtained 
                         directly from GNSS data. With regard to the other results, it was 
                         observed that LDIX and DIX indices showed small discrepancies in 
                         the absence of ionospheric variations of high-amplitude. Another 
                         relevant point observed were the limitations that the DIX index 
                         presented concerning the detection of daytime ionospheric 
                         disturbances. In contrast, the LDIX index was able to detect such 
                         disturbances, varying its value in a gradual way. It was also 
                         verified that the DIX presented disagreements to the LDIX, 
                         indicating non-existent TEC disturbances. These variations were 
                         classified as false positives results in the analysis. In 
                         addition, a strong relationship was observed between the physical 
                         processes observed in the foF2 parameter and the disturbances 
                         observed in the LDIX, which confirms the LDIX physical 
                         significance. Thus, the LDIX index showed to be superior to DIX, 
                         since it did not present the same physical similarity observed in 
                         LDIX with respect to the foF2 parameter. Finally, it was verified 
                         that the LDIX index is able to detect ionospheric responses due 
                         overshielding electric fields, Disturbance Dynamo Electric Fields 
                         (DDEF) and plasma bubbles in a localized way.",
            committee = "Wrasse, Cristiano Max (presidente) and DeNardin, Clezio Marcos 
                         (orientador) and Nogueira, Paulo Alexandre Bronzato (orientador) 
                         and Takahashi, Hisao and Mendes J{\'u}nior, Odim",
         englishtitle = "Development and analysis of an ionospheric index based on TEC 
                         data",
             language = "pt",
                pages = "188",
                  ibi = "8JMKD3MGP3W34R/3ST7PHB",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3ST7PHB",
           targetfile = "publicacao.pdf",
        urlaccessdate = "25 nov. 2020"
}


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