Left panel: Snapshot of the coronal magnetic field in a model where the coronal dynamics and heating is studied in the MHD approximation, with driving (as well as sunspots) supplied ab initio by the sub-photospheric part of the model. Right panel: the corresponding chromospheric (dark) and coronal (yellow and red) temperature structure. Red indicates temperatures in excess of 10 million K. The rotating sunspot at the lower left in the left-hand side panel is seen in front of the projected photospheric surface in the right-hand side panel. The simulation was performed with the Stagger code.