Event Details

Filling of the Van Allen Belt slot region: electron loss to the atmosphere

The Van Allen radiation belts are a region of highly energetic charged particles inside the Earth’s magnetosphere. They are often illustrated as two tori encircling Earth: the outer belt being primarily electrons; the inner belt dominated by protons. Between them lies a gap, often referred to as the slot region. In reality the structure of the belts changes in response to space weather: particle fluxes rapidly growing and dropping, altering the overall structure.

In this seminar I will present observations of times when the slot region is filled and consider the cause and duration of these events. Data from a radar in Antarctica shows that the subsequent loss of particles is via precipitation into the atmosphere, reaching as low as the top of the stratosphere. This has potential importance for our understanding of ozone destruction, polar climate variability and the extent of its effects.