TITLE:
Effect of High-Speed Solar Winds Turbulence Upstream of the Earth’s Magnetosphere: Case of the Outer Minima of Solar Cycles 20, 21, 22, 23 and 24
AUTHORS:
Inza Gnanou, Salfo Kabore, Aristide Marie Frédéric Gyebre, Christian Zoundi, Jean-Louis Zerbo, Frédéric Ouattara
KEYWORDS:
Solar Wind, Outer Minimum, Magnetosphere, Geomagnetic Field, Solar Disturbances
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.13 No.7,
July
27,
2023
ABSTRACT: Highly turbulent environment, the
solar wind is a stream of very energetic particles mainly made of protons and
electrons. During its trip in the interplanetary space, this solar flow becomes
more accelerated during the outer minima (descending phases) of the solar
cycles and can therefore influence all of humanity and its technology. These
disturbances lead to socio-economic consequences requiring a precise knowledge
of the climate variability. Using a statistical approach, we evaluate the
response of the Earth’s magnetosphere to the High-Speed Solar Winds (HSSW)
forcing during the peaks of the last five outer minima. To do so, 1UA data of
solar wind and magnetic field parameters
were extracted from OMNI browser. Analysis of the energetic solar plasma particles
shows that strong geomagnetic field variations can occur even in the absence of
large solar disturbances. While the normalized reconnection rate was estimated
to be ~21% of the total variance of the magnetospheric variables, the upstream
of the magnetic cavity was perturbed 80% of the time with large energies
recorded. As a result, Earth’s magnetosphere becomes denser (i.e., more
drag), which is a problem for spacecraft. Thus, the coupled solar
wind-magnetosphere system follows scale-invariant dynamics and is in a state
far from equilibrium. Our analysis provides insight into the main cause of
geomagnetic storms with more than 97% of HSSW imposed in the range 300 - 850
km/s. These high-speeds lead to auroras that can disrupt electrical and
communication systems.