Interhemispheric Asymmetries in Magnetosphere and Ionosphere Magnetic Field Residuals Between Swarm Observations and Earth Magnetic Field Models

We present a statistical study of magnetic field vector residual between Swarm observations and two Earth models: the 13th generation International Geomagnetic Reference Field (IGRF) model CHAOS-7 model. Statistics these residuals are important for estimating potential errors satellite operations when using models as reference, well magnetosphere-ionosphere-thermosphere studies examining energy input into system. Magnetic calculated differences estimation at positions from 2014 to 2020. both increase geomagnetic activity level increases, largest magnitude difference can be around 1800 nT with relatively small angle differences. The shows lower compared IGRF-13. North-south hemispheric asymmetries seen in high Kp values larger than 6 southern hemisphere (SH) having more frequent occurrence 300 nT, especially during SH summer. Most large appear high-latitude region seeing additional South Atlantic Anomaly region. Midnight noon sectors show strongest interhemispheric asymmetries. northern above 75° latitude throughout all local times SH. Identifying under levels is helpful studying response ionospheric disturbances hemispheres.