Effects of the Sun on the Earth's environment

Solar disturbances are observed to have significant effects in near-Earth s pace. Over the past half-century of observation, a relatively clear picture has developed of how and why the typical solar wind - as well as the most extreme solar events - drive geospace responses. It is clear that magnetosp heric substorms, geomagnetic storms (both recurrent and aperiodic events), and even certain atmospheric chemical changes have their origins in the sol ar-terrestrial coupling arena. High-speed solar wind streams and fast coron al mass ejections (CMEs) can often have strong interplanetary shock waves a nd southward magnetic fields which can initiate strong storm responses. We demonstrate in this review that available modem space-observing platforms a nd ground facilities allow us to trace drivers from the Sun to the Earth's atmosphere. This allows us to assess quantitatively the energy transport th at occurs throughout the Sun-Earth system during both typical and extreme c onditions. Hence, we are continuously improving our understanding of "space weather" and its effects on human society. (C) 2000 Elsevier Science Ltd. All rights reserved.