At http://spaceweather.com (scroll down to March 30th, 2014) we have a solar flare causing a 'rare magnetic crochet' (on March 29th). Radiation in the flare caused a surge in the ionisation of Earth's upper atmosphere – and this led to the magnetic crochet. This is a ripple in Earth's magnetic field caused by electrical currents flowing in air 60 to 100km above our heads. Unlike geomagnetic disturbances that arrive with CMEs days after a flare a magnetic crochet occurs while the flare is still in progress. The explosion, incidentally, also hurled a CME into space – mostly not affecting the Earth. However, new flares are expection in the near future.
