Example of three mapping scenarios when applying the Tsyganenko model to find the bursty bulk footpoint (indicated by a star). (a) The footpoint was calculated using four different Tsyganenko models, and all met both criteria. (b) Both Tsyganenko models (T89 and T96) returned both footpoints at the Earth’s surface, but the shape of the field line did not met the second criterion (c). The footpoint computed with the T89 model did not return a footpoint in the Southern Hemisphere.