@InProceedings{AlvesCaraHartBarb:2018:GeInCu,
author = "Alves, Livia Ribeiro and Caraballo, R. and Hartmann, G. A. and
Barbosa, C. S.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Facultad
de Ingenieria (Udelar)} and {Universidade Estadual de Campinas
(UNICAMP)} and {Observat{\'o}rio Nacional (ON/MCTI)}",
title = "Geomagnetically induced currents measured at low latitude during
the space disturbances on 07-08 September, 2017",
year = "2018",
organization = "Latin American Conference on Space Geophysics, 11. (COLAGE)",
abstract = "Geomagnetically induced currents (GICs) were rst described by W.
H. Barlow in 1849 as anomalous currents in telegraphic wires.
These phenomena are currently understood as a ground eect arising
from a chain of events in the Sun-Earth system. They are mainly
observed at power networks and their amplitudes are controlled by
a combination of geophysical conditions and network parameters.
The magnetic disturbances detected on the ground came from the
coupling of highly disturbed solar wind plasma propagating through
the interplanetary medium which eventually impinges on the Earth's
magnetosphere. The perturbed magnetosphere-ionosphere coupling can
produce intense currents systems that can induce strong
geoelectric elds at the Earth's surface, which in turn generate
currents that can ow through grounded technological infrastructure
as it oers low-resistance pathways. The available GIC datasets
show that at high latitudes GIC records can reach hundreds of
Amperes, leading to failure at transformers, such as reported at
Hydro-Quebec, in Canada in 1989 and at Malmo, in Sweden in 2011.
Due to the higher GIC intensities recorded at auroral regions, the
GIC data at mid-to-low latitudes had been scarce. However, more
recent works have shown that GIC can reach tenths of Amperes
during intense sudden commencement and at the peak of geomagnetic
storms. Despite intense geomagnetic storms are rare during the
solar cycle declining phase, on the period of 04-06 September 2017
solar activity was increased due to the evolution of the active
region 2673, thus it was observed two CME propagating Earthwards.
The geomagnetic storm initiated at the beginning of 07 September
evolving to one day long main phase as high as -140 nT. Besides
the geomagnetic disturbances due to the ICME shock, also at least
two intense solar ares (at 06 and 10 September 2017) causing spike
disturbances in the geomagnetic eld measured at the ground.
Considering the relevance of the intense space disturbance during
the solar cycle declining phase, in this work, we use de
Lethinen-Pirjola model to calculated GIC at low latitude power
network located at Brazil and Uruguay during the period of the
disturbance. The GIC results obtained during the solar cycle
declining phase, compared to the long-term survey available at
literature, are used to verify the signicance of GIC intensity
observed at low latitude measured after the ICME disturbance and
also with the are geomagnetic disturbance registered after a
long-term of solar cycle condition.",
conference-location = "Buenos Aires, Argentina",
conference-year = "16-20 abr.",
language = "en",
urlaccessdate = "28 abr. 2024"
}