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Neutron monitors have been the premier ground-based instruments for monitoring the near-Earth cosmic ray flux for more than 70 years. It is essential to continue with such measurements in order to extend this unique long-term time series. Moreover, with the recent interest of the aviation industry to space weather effects, and especially the radiation risk posed by solar energetic particles and galactic cosmic rays, it is vital to extend the current neutron monitor network in order to provide near-real-time measurements to the space weather community. In this paper we discuss a new electronics system that was retrofitted to the SANAE neutron monitor in Antarctica. We present initial results from this system, featuring very high temporal resolution and discuss the techniques applied to the data analysis. Based on these successful upgrades, we are confident that this system can be used to rejuvenate the aligning neutron monitor network, and even possibly to revive some of the decommissioned instruments. [ABSTRACT FROM AUTHOR]

The nucleation process is the first step in creating cloud condensation nuclei (CCN). There was a report on cosmic rays and cloud cover correlation in 2007 but whether the correlation is true remains a debated issue. CERN has initiated the CLOUD project to study the effects of nucleation. Fangqun Yu also reported a parameterization scheme for including the effect of atmospheric ionization on the generation of pre-CCN ion clusters. Our study explored past literature and used existing parameterization, measurement campaign datasets and ionization simulations to set an upper limit on the contribution of cosmic rays to the nucleation process. We have chosen the Jan 2005 solar energetic particle (SEP) event as the strongest SEP event in the past 60 years. We also chose to investigate the effect at Antarctica where the cosmic ray intensity is most prominent, and considered the actual atmospheric variables there. We calculate the effects of the background galactic cosmic rays (GCR) and relativistic solar particles in comparison with other nucleation sources such as stochastic heterogeneous nucleation particles. [ABSTRACT FROM AUTHOR]