Supermagnetic storms: hazard to society

Abstract

Magnetic storms are an important component of space weather effects on Earth. Superintense magnetic storms (defined here as those with Dst < 500 nT, where Dst stands for the disturbance storm time index that measures the strength of the magnetic storm), although relatively rare, can be hazardous to technological systems in space as well as on the ground. Such storms can cause life-threatening power outages, satellite damage, communication failures, and navigational problems. The data for such magnetic storms during the last 50 years is rather scarce. Research on historical geomagnetic storms can help to create a good database for intense and superintense magnetic storms. The superintense storm of 1–2 September 1859 is analyzed in the light of new knowledge of interplanetary and solar causes of storms gained from the space-age observations. We will discuss the results in the context of some recent intense storms and also the occurrence probability of such superstorms.