@InProceedings{EspinosaSarmientoPadiSilv:2018:EsAmGe,
author = "Espinosa Sarmiento, Karen Viviana and Padilha, Ant{\^o}nio Lopes
and Silva, Ligia Alves da",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)}",
title = "Estimate of the amplitude of geomagnetically induced currents
(gic) at different places in brazil duringmagnetic storms occurred
in the year 2015",
year = "2018",
organization = "Latin American Conference on Space Geophysics, 11. (COLAGE)",
abstract = "Geomagnetic induced currents (GIC) detected on the Earths surface
are related to extreme solar events and may represent a signicant
danger to technological systems installed both in space and in the
ground. Its eects are relatively well studied in auroral and
midlatitude regions, but there are still few studies in low
latitudes and near the magnetic equator. To evaluate its eects in
the low latitude region of South America and thus contribute to
the development of new mechanisms that may help to minimize its
possible impact, the intensity of the GIC in four locations in the
Brazilian territory is here evaluated during four geomagnetic
storms that occurred during the year 2015. Geomagnetic eld
variation data recorded by uxgate magnetometers of the Brazilian
Space Weather program at INPE (EMBRACE) are available during these
storms. Using information from the electrical conductivity
distribution below each magnetic station, geoelectric eld
variations were derived for the period of the magnetic storms.
Subsequently, GIC values were estimated using the Lehtinen-Pirjola
(LP) engineering model and available information from a 500 kV
transmission grid located in Central Brazil (around the Furnas
substation node in Itumbiara, State of Goias ). After validating
the numerical calculations comparing with the GIC data measured at
this substation, the electric power transmission grid at Itumbiara
was hypothetically shifted to the stations where measurements of
the geomagnetic eld are available. The maximum GIC amplitude
estimated by the LP model was about 8A during the main phase of a
magnetic storm on June 21 (Dst = -204 nT) at a station in the
center-west Brazil. Although this station is aected by the diurnal
currents of the equatorial electrojet, the comparison with the
other storms showed that, besides the large dH/dt of this storm,
the main responsible for the GIC is the high resistivity of the
rocks below this station.",
conference-location = "Buenos Aires, Argentina",
conference-year = "16-20 abr.",
language = "en",
urlaccessdate = "28 abr. 2024"
}