Geomagnetic Influence on Antarctic Climate – Evidences and Mechanism

Abstract

This paper presents a mechanism through which geomagnetic field intensity and its temporal variations could affect diversity of Antarctic temperature trends, reported recently. It consists of: (i.) modulation of energetic particle fluxes, continuously or sporadically entering Earth's atmosphere; (ii.) ozone formation in the lower stratosphere, initiated by precipitating energetic particles, with different mechanisms for galactic and solar protons; (iii.) modulation of tropopause temperature and humidity by the ozone; (iv) greenhouse warming or cooling, depending of the sign of humidity anomaly. Provided are also evidences confirming validity of this mechanism. The spatial distribution of correlation coefficients of surface temperature with: (i) geomagnetic field intensity,(ii)  total ozone and (iii) specific humidity at 150 hPa shows a persistent coherence between all of them over West Antarctica. Moreover, analysis of time series reveals that in this sector the ozone values are permanently lower, while specific humidity near the tropopause remains persistently higher than that in the East Antarctica, during all examined years. This means that during the passed half a century the near surface air temperature in the West Antarctica is warmed (by the increased near tropopause humidity), while in the East Antarctica it is cooled, due to the reduced water vapour making the atmosphere  more  transparent for the long-wave radiation emitted  from the Earth. Thus one of the hotly discussed problems for cooling trends of the Eastern Antarctica, in the context of contemporary global warming, could be easily solved by taking into account the geomagnetic field influence on climate.