Wave energy budget analysis in the Earths radiation belts uncovers a missing energy.
- Author(s): Artemyev, A
- Agapitov, O
- Mourenas, D
- Krasnoselskikh, V
- MOZER, Forrest S.
- et al.
Published Web Locationhttps://doi.org/10.1038/ncomms8143
Whistler-mode emissions are important electromagnetic waves pervasive in the Earths magnetosphere, where they continuously remove or energize electrons trapped by the geomagnetic field, controlling radiation hazards to satellites and astronauts and the upper-atmosphere ionization or chemical composition. Here, we report an analysis of 10-year Cluster data, statistically evaluating the full wave energy budget in the Earths magnetosphere, revealing that a significant fraction of the energy corresponds to hitherto generally neglected very oblique waves. Such waves, with 10 times smaller magnetic power than parallel waves, typically have similar total energy. Moreover, they carry up to 80% of the wave energy involved in wave-particle resonant interactions. It implies that electron heating and precipitation into the atmosphere may have been significantly under/over-valued in past studies considering only conventional quasi-parallel waves. Very oblique waves may turn out to be a crucial agent of energy redistribution in the Earths radiation belts, controlled by solar activity.