Variation of Solar, Interplanetary and Geomagnetic Parameters during Solar Cycles 21-24

Storm Sudden Commencements Without Interplanetary Shocks

“…Correct identification of SSC drivers is important for understanding the dynamics of the Earth's magnetosphere. The relationship between the other geomagnetic activity indices and solar wind parameters has been studied (Oh 2013;Oh & Kim 2013;Kim & Chang 2014a, b). In this paper, we present a statistical study of geomagnetic storms focused on SSCs without IP shocks.…”

Frequency of Solar Spotless Days and Flare Index as Indices of Solar Cycle Activity

“…To compare the hemispheric variation, we have divided the analyzed period into four periods which the leading sunspots have the same magnetic polarity, such as from solar maximum to solar maximum. Oh & Kim (2013). According to Fig.…”

“…As the change of official onset time of solar cycle 24 has been made by the US Solar Cycle 24 Prediction Panel, the low solar activity was issued more. Especially, Oh & Kim (2013) have mentioned the preceding studies of low solar activity such as solar wind, total solar irradiance associated with the Earth's climate, and the variation of oceanic temperature. Most of the studies explained the status of the solar cycle 23/24 minimum by comparison with the past grand minimum of Maunder or Dalton minimum.…”

“…Most of the studies explained the status of the solar cycle 23/24 minimum by comparison with the past grand minimum of Maunder or Dalton minimum. Oh & Kim (2013) also introduced the solar cyclic variation of ten solar, interplanetary geomagnetic (SIG) parameters and their remarkable decrease at the solar cycle 23/24 minimum.…”

“…The solar cyclic variation of total solar irradiance has been correlated with the sunspot number. However, Oh & Kim (2013) have suggested that the cyclic variation of sunspot number couldn't explain the variation of total solar irradiance any more. Thus, the approach by the frequency of sunspot appearance on the solar disk and the length of solar cycle is introduced to explain the solar activity instead of the sunspot number.…”