What causes geomagnetic activity during sunspot minimum?

Cyclic behaviour of sunspot activity during the Maunder minimum

We study the behaviour of sunspot activity in 16101750, i.e. just prior to, during and slightly after the Maunder minimum, using the new series of group sunspot numbers (Hoyt & Schatten 1998). We apply the delayed component technique and show that, while the transition from the normal cyclic evolution to the minimum was very abrupt, the recovery from the minimum was gradual, proceeding through ...

Geomagnetic activity and wind velocity during the Maunder minimum

Following a given classi®cation of geomagnetic activity, we obtained aa index values for the Maunder minimum (1645±1715). It is found that the recurrent and ̄uctuating activities were not appreciable and that the shock activity levels were very low. The aa index level was due almost entirely to the quiet days. Calculated average solar-wind velocities were 194.3 km s from 1657 to 1700 and 218.7 ...

spectral solar irradiance lower during the recent low sunspot minimum ?

Dayside ionospheric response to recurrent geomagnetic activity during the extreme solar minimum of 2008

[1] Global observations of electron density profiles from the COSMIC satellites are used to investigate, for the first time, the altitudinal dependence of the ionospheric response to the recurrent geomagnetic activity at different latitudinal regions during the extreme solar minimum period of 2008. Our results show that the 9-day oscillations in NmF2 are out of phase with those in Kp at high la...

Gps-derived Local Tec Mapping over Peninsula Malaysia during Solar Minimum of Sunspot Cycle 24

The ionosphere is the major contributor of errors in Global Positioning System (GPS), especially during the 11-year sunspot cycle. The incoming 11-year sunspot cycle is expected to peak in 2013. The ionosphere condition is distinctly severe during ionospheric disturbances caused by high solar activity, which raises the question of how will this affect the ionosphere in the equatorial region, es...