Thermospheric Neutral Winds: A Driver of the Earth’s Inner Radiation Belt to Be Reckoned With

<p>Neutral winds have long been viewed as a driver of Jupiter&#8217;s radiation belts. On the other hand, the impact of thermospheric neutral winds in driving plasma dynamics in the Earth&#8217;s inner magnetosphere is yet to be quantified. We now have the appropriate combination of data and physics-based model to address this fundamental science question.</p><p>In this work, we revisit the local time asymmetry of the equatorial electron intensity observed in the innermost radiation belt (L=1.30). We combine in-situ field and particle observations, together with a physics-based coupled model, RCM-CTIPe, to determine whether the dynamo electric fields produced by tidal motion of upper atmospheric winds flowing across the Earth&#8217;s magnetic field lines are the main drivers of the drift-shell distortion observed in the Earth&#8217;s inner radiation belt.</p><p>Our results provide a first quantification of the contribution of the neutral wind in transporting the trapped energetic particles of the Earth&#8217;s inner radiation belt.</p>