Some Polarity Conditions in Corpuscular Events

We present some refinements of the previously reported magnetic polarity conditions in solar-terrestrial relations. Appropriately selected subsets were used from the longest available data sets, the geomagnetic aa-index and the surface air temperature. The solar corpuscular impacts have conspicuous effects in the tropospheric behaviour. We reported previously a new kind of semi-annual fluctuation and opposite tropospheric responses to the effects coming from different regions of the Sun as well as their dependence on the orientation of the solar main magnetic dipole. It is shown in the present paper that the semi-annual fluctuation governed by shock and fluctuating disturbances (which originate from the lower-latitude solar regions) exhibits sign reversals in consecutive cycles. The effect can be detected only in the absence of recurrent disturbances (coming mainly from the polar regions). This complex phenomenon implies that the corpuscular events may preserve some of their polarity conditions of their specific solar origin even at the Earth's distance, and on the other hand the small-scale structure of the IMF plays an important role in the link between the solar particles and the tropospheric response.