Effects of the Sun on the Earth's environment

Solar disturbances are observed to have significant effects in near-Earth space. 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 magnetospheric substorms, geomagnetic storms (both recurrent and aperiodic events), and even certain atmospheric chemical changes have their origins in the solar-terrestrial coupling arena. High-speed solar wind streams and fast coronal mass ejections (CMEs) can often have strong interplanetary shock waves and southward magnetic fields which can initiate strong storm responses. We demonstrate in this review that available modem space-observing platforms and ground facilities allow us to trace drivers from the Sun to the Earth's atmosphere. This allows us to assess quantitatively the energy transport that occurs throughout the Sun-Earth system during both typical and extreme conditions. Hence, we are continuously improving our understanding of "space weather" and its effects on human society. (C) 2000 Elsevier Science Ltd. All rights reserved.