Variable terrestrial particle environments during the galactic orbit of the sun

Abstract

The effects of variable terrestrial environments of the Sun during its galactic orbit are discussed. Emphasis is put on the energetic particle populations, like pick-up ions, anomalous and galactic cosmic rays. After putting the analysis briefly into the context of the ongoing debate regarding a cosmic ray-terrestrial climate link, we study the structure of the heliosphere in various interstellar environments, particularly in dense clouds of atomic hydrogen. We continue with a computation of the energy spectra of both anomalous and galactic cosmic rays for galactic regions located in clouds and/or in galactic spiral arms. In the light of these results we discuss the consequences for the terrestrial and planetary environments, as well as for small solar system bodies. © 2006 Springer. All Rights Reserved.