Particle Precipitation Effects on Convection and the Magnetic Reconnection Rate in Earth's Magnetosphere

We investigate the connection between particle precipitation in the ionosphere to both the subsolar distance of the magnetopause and the reconnection rate using the OpenGGCM‐CTIM‐RCM model. We simulated two events, a calm period on 4 May 2005 and a storm period on 17 March 2013. We find that scaling the precipitation energy flux by several orders of magnitude, conductivities in the auroral oval are influenced which, in turn, influence the cross polar cap potentials. With the change in conductance, magnetospheric convection is enhanced or reduced, and the location of the subsolar distance of the magnetopause can change by up to one RE. The investigation of the reconnection rate for the varying precipitation simulations using the Hesse‐Forbes‐Bern method shows that particle precipitation affects the magnetic reconnection rate in these two events. The most notable differences, up to 40%, occur on short time scales, that is, hours. A relation for longer time scales (tens of hours) between precipitation and reconnection for these two events is more difficult to ascertain. Differences in cross polar cap potential (CPCP) and R can be explained by viscous interactions and polar cap saturation. We find that when precipitation was decreased, resulting in low polar conductance, viscous interactions are strong and CPCP is higher than R. For high precipitation, high conductance cases the polar cap is in the saturation regime and CPCP is lower than R. We find hemispheric asymmetries in the cross polar cap potential and in the calculated reconnection rate derived from the Northern and Southern Hemispheres. Key Points By varying precipitation in OpenGGCM, cross polar cap potential and magnetic reconnection rate change and are not always the same We use the Hesse‐Forbes‐Birn method to calculate the reconnection rate of the Earth's magnetosphere for both storm and quite time periods Reconnection rate is affected by varying precipitation on short times scales (hours), but not for larger times scales (tens of hours)