Connection Between Solar Hemispheric Toroidal Cycles and Geomagnetic Variations

Geomagnetic Semiannual Variation Is Not Overestimated and Is Not an Artifact of Systematic Solar Hemispheric Asymmetry

[1] Mursula et al. [2011] (MTL11) suggest that there is a 22-year variation in solar wind activity that coupled with the variation in heliographic latitude of the Earth during the year, gives rise to an apparent semiannual variation of geomagnetic activity in averages obtained over several solar cycles. They suggest that the observed semiannual variation is seriously overestimated and is largel...

Correlations between SAR arc intensity and solar and geomagnetic activity

We present a study of statistical relationships between SAR arc intensities acquired by the Paci®c Northwest Laboratory Photometer Network during 1978±1988 and solar and geomagnetic activity indices Dst; F 10:7, and Kp by use of the method of multiple regression analysis. We found signi®cant correlations between intensity and all of the indices involved. In the present work we show for the ®rst...

Detecting Oscillations Hidden in Noise: Common Cycles in Atmospheric, Geomagnetic and Solar Data

In this chapter we present a nonlinear enhancement of a linear method, the singular system analysis (SSA), which can identify potentially predictable or relatively regular processes, such as cycles and oscillations, in a background of colored noise. The first step in the distinction of a signal from noise is a linear transformation of the data provided by the SSA. In the second step, the dynami...

The 13.5-day periodicity in the Sun, solar wind, and geomagnetic activity: The last three solar cycles

We make a detailed analysis of the 13.5-day periodicity of the solar chromosphere, the nearEarth solar wind, interplanetary magnetic field and geomagnetic activity during the last three solar cycles. The 13.5-day periodicity is a real quasi-periodicity whose amplitude varies sizably with time, attaining occasionally values larger than, for example, the amplitude of the 27-day periodicity. In ca...

The geomagnetic field variations and earthquake activity