An alternative way to identify local geomagnetically quiet days: a case study using wavelet analysis

Autor(es)

Klausner, Virginia ^{[1, 2, 3]} ; Rodriguez Papa, Andres Reinaldo ^{[2, 4]} ; Nicole Candido, Claudia Maria ^[1] ; Domingues, Margarete Oliveira ^[1] ; Mendes, Odim ^[1]

Afiliação do(s) autor(es)

^[1] Natl Inst Space Res INPE, BR-12227010 Sao Jose Dos Campos, SP - Brazil

^[2] Natl Observ, BR-20921400 Rio De Janeiro, RJ - Brazil

^[3] Vale do Paraiba Univ UNIVAP, BR-12244000 Sao Jose Dos Campos, SP - Brazil

^[4] Rio de Janeiro State Univ UERJ, BR-20550900 Rio De Janeiro, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Annales Geophysicae; v. 34, n. 4, p. 451-462, 2016.
• Citações Web of Science: 3

Resumo

This paper proposes a new method to evaluate geomagnetic activity based on wavelet analysis during the solar minimum activity (2007). In order to accomplish this task, a newly developed algorithm called effectiveness wavelet coefficient (EWC) was applied. Furthermore, a comparison between the 5 geomagnetically quiet days determined by the Kp-based method and by wavelet-based method was performed. This paper provides a new insight since the geomagnetic activity indexes are mostly designed to quantify the extent of disturbance rather than the quietness. The results suggest that the EWC can be used as an alternative tool to accurately detect quiet days, and consequently, it can also be used as an alternative to determine the Sq baseline to the current Kp-based 5 quietest days method. Another important aspect of this paper is that most of the quietest local wavelet candidate days occurred in an interval 2 days prior to the high-speed-stream-driven storm events. In other words, the EWC algorithm may potentially be used to detect the quietest magnetic activity that tends to occur just before the arrival of high-speed-stream-driven storms. (AU)

• Processo FAPESP: 13/06029-0 - Técnicas wavelet aplicadas ao estudo de fenômenos eletrodinâmicos espaciais
• Beneficiário: Virginia Klausner de Oliveira
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 11/20588-7 - Estudo das variações geomagnéticas usando técnicas wavelet.
• Beneficiário: Virginia Klausner de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado