Semimonthly oscillation observed in the start time of equatorial Spread-F

Abstract

Abstract. Using data from airglow an all sky imager and a coherent backscatter radar deployed at São João do Cariri (7.4° S, 36.5° W) and São Luís (2.6° S, 44.2° W), respectively, the start time of equatorial Spread-F were studied. Data from a period of over 10 years was investigated from 2000 to 2010. The semimonthly oscillations were clearly revealed in the start time of plasma bubbles from Oi6300 airglow images during three periods (September 2003, September–October 2005, November 2005 and January 2008). Since the airglow measurements are not continuous in time, more than one cycle of oscillation in the start time of plasma bubbles cannot be observed from these data. Thus, coherent backscatter radar data appeared as an alternative to investigate the start time of the ionospheric irregularities. Semimonthly oscillation were observed in the start time of plumes (November 2005) and bottom type Spread-F (November 2008) with at least one complete cycle. Technical/climate issues did not allowed to observe the semimonthly oscillations simultaneously by the two instruments, but from September to December 2005 there was a predominance of this spread-F start time oscillation over Brazil. The presence of this oscillation certainly contribute to the day-to-day variability of spread-F.

Climatology of the Equatorial Plasma Bubbles Captured by FORMOSAT‐3/COSMIC

“…In addition to nonmigrating diurnal tides, Paulino et al (2019) have shown the start time of EPBs displaying a semimonthly oscillation. They suggested that the quasi 16‐day planetary waves and lunar semidiurnal tide may control either the start time of EPBs or the amplitude of the PRE, providing additional evidence that lower atmospheric forcing contributes to the day‐to‐day variability of EPBs.…”

Morphological Features of Ionospheric Scintillations During High Solar Activity Using GPS Observations Over the South American Sector

“…Besides the planetary waves, there is growing evidence that the lunar semidiurnal tides have a great importance in the generation of spread F (e.g., Paulino et al, 2019). Using OI 630 nm all-sky imaging and coherent backscatter radar in the equatorial region over South America, Paulino et al (2019) observed that a semimonthly oscillation due to quasi 16 days planetary waves and lunar semidiurnal tide can modulate the PRE responsible to generate ionospheric irregularities. Figure 1b shows a map with the GPS-TEC stations used to study the distance between adjacent plasma bubbles (also referred as interbubble distance).…”

“…They showed that ultrafast Kelvin waves in the mesosphere-low thermosphere region could modulate the vertical drift and explain the oscillations observed in the ionospheric parameters. Besides the planetary waves, there is growing evidence that the lunar semidiurnal tides have a great importance in the generation of spread F (e.g., Paulino et al, 2019). Using OI 630 nm all-sky imaging and coherent backscatter radar in the equatorial region over South America, Paulino et al (2019) observed that a semimonthly oscillation due to quasi 16 days planetary waves and lunar semidiurnal tide can modulate the PRE responsible to generate ionospheric irregularities.…”

Compreensão Da Enfermeira Sobre Os Conflitos E Dilemas Éticos Na Vivência De Morte Da Pessoa Cuidada No Período Perioperatório

“…Em se tratando da transfusão de sangue, a tomada de decisão é impactante, podem emergir dilemas éticos relacionados à transfusão sanguínea em pessoas com restrições religiosas, devido ao desejo dos enfermeiros de salvar uma vida e ao mesmo tempo de respeitar a autonomia desses frente à possibilidade de optar em não ser transfundido (SOUZA, 2014). As enfermeiras desvelam conflitos e dilemas éticos quando se deparam com situações de doações de órgãos, Na discussão acerca da doação de órgãos há um conflito de consciência que emerge de pensamentos sobre a finitude e sua relação com o corpo após a morte; o que desperta para inúmeras questões éticas por envolver a autonomia e os direitos dos pacientes (PAULINO;TEIXEIRA, 2009). No tocante a vivência de casos em que o prognóstico é ruim e que precisa obedecer as recomendações para evitar a distanásia, as enfermeiras ressaltam que os aspectos éticos devem ser respeitados, ao tempo que revelam que alguns procedimentos cirúrgicos acabam por prolongar a vida da pessoa por muitos anos.…”