The ozone layer protects us from the harmful UV radiation and the Earth's magnetosphere prevents charged particles from reaching us, thus making life possible on Earth. When gusts of those charged particles reach the Earth, they will disturb the magnetosphere - the phenomenon is called a geomagnetic storm - and will be ejected towards the magnetic poles. The event can create shimmering curtains of coloured light, northern lights or auroras, which are more or less harmless. Other effects are much more serious.
Higher up in the atmosphere ozone prevents harmful ultraviolet radiation from reaching the Earth. Lower down, it has a negative effect on all organisms.
In the picture the European ERS 2 is studying the ozonosphere (blue).
