Auroral substorm studies, ionosphere studies using superDARN and e-POP satellite instruments, sunspot-cycle-driven space weather and links to meteorological weather

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One of the most energetic effects of the impact upon the Earth of the solar wind is the production of substorms resulting in brilliant displays of auroras and strong currents and particle motions in the ionosphere more than 100 km above ground. We plan to use ground-based instruments to study the displays, currents and motions, and then to use the upcoming Canadian e-POP satellite to study the effects from heights of 500-2000 km in and just above the ionosphere. The interaction of the solar wind with the Earth takes place in the large outer region of magnetic field - the magnetosphere -from which disturbances flow down to the ionosphere. Substorms have three stages, the growth phase, the expansive onset phase in which the auroras in the ionosphere brighten and expand poleward and east-west, and the recovery phase. Two main mechanisms have been proposed to account for the explosive onset, namely partial diversion of currents flowing from the morning to evening side of the nightside magnetosphere (the magnetotail) down to the ionosphere, and "magnetic reconnection" which transfers energy from the Earth's magnetic field to the charged particles that cause the auroras. The main purpose of the present proposal is to develop all aspects of a new substorm model I have proposed which incorporates both the above mechanisms. Although simple in principle, the model requires much development to study the processes in neighbouring regions of the nightside magnetosphere. The distorted magnetic fields in the magnetotail lead to three neighbouring layers in which the particle motions and currents of the outer two layers are opposite to those in the middle. This produces strong wave activity that leads to the magnetic reconnection that drives the onset phase. Finally, substorms are just one aspect of the Sun's changing behavior during 11-year sunspot cycles, which may soon disappear if the recent 18-year weakening of magnetic fields in sunspots continues. This last happened in 1645-1711 when European weather became very cold (the Little Ice Age). Part of this proposal is to reveal how the sunspot- cycle-related "space weather" leads to changes in the Earth's weather.