Fig. 3
![Fig. 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40623-020-01316-w/MediaObjects/40623_2020_1316_Fig3_HTML.png)
Swarm Alpha data distribution used for preliminary modelling attempts. Top: geographic distribution of the Swarm Alpha QD55° vector data selection; Middle: latitude versus time distribution of the QD55° data selection; Bottom: latitude versus time distribution of the QD20° data selection. In all plots, red for vector data and blue for scalar data