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Extrapolation codes in Cartesian geometry for modelling the magnetic field inthe corona do not take the curvature of the Sun's surface into account and canonly be applied to relatively small areas, e.g., a single active region. Wecompare the analysis of the photospheric magnetic field and subsequentforce-free modeling based on full-disk vector maps from Helioseismic andMagnetic Imager (HMI) on board solar dynamics observatory (SDO) and VectorSpectromagnetograph (VSM) of the Synoptic Optical Long-term Investigations ofthe Sun (SOLIS). We use Helioseismic and Magnetic Imager and VectorSpectromagnetograph photospheric magnetic field measurements to model theforce-free coronal field above multiple solar active regions, assuming magneticforces to dominate. We solve the nonlinear force-free field equations byminimizing a functional in spherical coordinates over a full disk excluding thepoles. After searching for the optimum modeling parameters for the particulardata sets, we compare the resulting nonlinear force-free model fields. Wecompare quantities like the total magnetic energy content and free magneticenergy, the longitudinal distribution of the magnetic pressure and surfaceelectric current density using our spherical geometry extrapolation code. Themagnetic field lines obtained from nonlinear force-free extrapolation based onHelioseismic and Magnetic Imager and Vector Spectromagnetograph data have goodagreement. However, the nonlinear force-free extrapolation based onHelioseismic and Magnetic Imager data have more contents of total magneticenergy, free magnetic energy, the longitudinal distribution of the magneticpressure and surface electric current density compared to the one from VectorSpectromagnetograph data.

Full-disk nonlinear force-free field extrapolation of SDO/HMI and SOLIS/VSM magnetograms