ESF network on space weather and the Earth's weather, SPECIAL

The phenomena in space that may cause space weather induced effects in the Earth's environment and their possible association with meteorological obse rvations, both on short- and long-term scales, is a controversial topic. Hi ghly energetic cosmic ray, solar and magnetospheric charged particles may h ave direct or indirect effects on the layers of the atmosphere with which t hey come into contact. The aim of the interdisciplinary European Science Fo undation (ESF) Network study on "Space Weather and the Earth's Weather: Ele ctrodynamic and Charged Particle Effects on the Stratosphere and Tropospher e" is to improve the scientific understanding of this topic within the Sun- Earth scenario. Its ultimate objective is to generate global, regional and local models to relate electrical changes in the atmosphere to the distribu tion of the highly energetic particles, and thereafter to examine and quant ify the relationship between such changes with the properties of the global atmospheric electric circuit and also the distribution of cloud and rainfa ll. This paper presents the scientific background behind the Network and it s objectives; the current acronym for the Network is SPECIAL - Space Proces ses and Electrical Changes Influencing Atmospheric Layers. (C) 2001 Elsevie r Science Ltd. All rights reserved.