Navegando por Assunto "Space weather"

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    Influence of geomagnetic disturbances on myocardial infarctions in women and men from Brazil
    (SPRINGERNATURE) Rezende, Luiz Felipe Campos de; Paula, Eurico Rodrigues de; Muella, Marcio Tadeu de Assis Honorato; Dutra, Severino Luiz Guimaraes; Rosa, Reinaldo Roberto; Saldiva, Paulo Hilário Nascimento; Ometto, Jean Pierre Henry Balbaud
    Background: Understanding the role of space weather, specifically Geomagnetic Disturbances (GMDs) caused by solar activity, on health outcomes is unclear. One emerging link includes the impact of space weather on myocardial infarctions (MI). In this study we examined the correlation between MI and GMDs in Brazil. Methods: We used a database from the public health in Brazil, focusing on the city of São José dos Campos (23 degrees 10 ' 44 '' S, 45 degrees 53 ' 13 '' W), located in the state of São Paulo, during the period of 1998-2005. We focused on admissions for MIs, which included a total of 871 men and 469 women. We categorized the MI data into three age groups: age 30 and younger, age 31-60, and age over 60. Additionally, we incorporated Planetary Index (Kp) data as an indicator of variations in the Earth's geomagnetic field resulting from solar disturbances, categorized as quiet, moderate, or disturbed days. In our analysis, we employed two methods: statistical counting and the unsupervised clustering known as K-Means, considering the attributes of age, sex, and geomagnetic condition. Results: Here we show that geomagnetic conditions have an impact on MI cases, particularly for women. The rate of relative frequency of MI cases during disturbed geomagnetic conditions is almost three times greater compared to quiet geomagnetic conditions. Using the unsupervised K-Means algorithm, the results indicate that the group associated with disturbed geomagnetic conditions has a higher incidence of MIs in women. Conclusions: Overall, our results provide evidence that women may exhibit a higher susceptibility to the effects of geomagnetic disturbances caused by solar activity on MI.
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    Ionospheric storm due to solar Coronal mass ejection in September 2017 over the Brazilian and African longitudes
    (Elsevier) Fagundes, Paulo Roberto; Tsali-Brown, Vera Yesutor; Pillat, Valdir Gil; Arcanjo, Mateus de Oliveira; Venkatesh, Kavutarapu; Habarulema, John Bosco; Bolzan, Maurício José Alves; Jesusm Rodolfo F. de; Abreu, Alessandro José de; Tardelli, Alexandre; Vieira, Francisco; Denardini, Clezio Marcos
    Coronal mass ejection (CME) occurs when there is an abrupt release of a large amount of solar plasma, and this cloud of plasma released by the Sun has an intrinsic magnetic field. In addition, CMEs often follow solar flares (SF). The CME cloud travels outward from the Sun to the interplanetary medium and eventually hits the Earth’s system. One of the most significant aspects of space weather is the ionospheric response due to SF or CME. The direction of the interplanetary magnetic field, solar wind speed, and the number of particles are relevant parameters of the CME when it hits the Earth’s system. A geomagnetic storm is most geo-efficient when the plasma cloud has an interplanetary magnetic field southward and it is accompanied by an increase in the solar wind speed and particle number density. We investigated the ionospheric response (F-region) in the Brazilian and African sectors during a geomagnetic storm event on September 07–10, 2017, using magnetometer and GPS-TEC networks data. Positive ionospheric disturbances are observed in the VTEC during the disturbed period (September 07–08, 2017) over the Brazilian and African sectors. Also, two latitudinal chains of GPS-TEC stations from the equatorial region to low latitudes in the East and West Brazilian sectors and another chain in the East African sector are used to investigate the storm time behavior of the equatorial ionization anomaly (EIA). We noted that the EIA was disturbed in the American and African sectors during the main phase of the geomagnetic storm. Also, the Brazilian sector was more disturbed than the African sector.