Solar flares are intense, short-lived brightenings that occur near sunspots on the Sun's surface. Large geomagnetic storms, intense auroral displays, large energetic particle events in interplanetary space, and major shock wave disturbances in the solar wind often occur in close association with large solar flares. Over the years, the common association of these events in near-Earth space with solar flares led to a paradigm of cause and effect in which large solar flares came to be understood as the fundamental cause of these disturbances.
Certain aspects of this paradigm were developed in the early 1930s [e.g., Hale, 1931], and by the early 1960s it had become part of the underlying dogma central to the discipline of solar-terrestrial physics. This paradigm still dominates the popular perception of the relationship between solar activity and interplanetary and geomagnetic events and continues to provide much of the pragmatic rationale for the study of the solar flare phenomenon.