Extended Data Fig. 7: Stability of velocity field.

a–f, Latitude–local time distributions of the velocities obtained from the first half (from 23 December 2016 to 13 February 2018; a–c) and the second half (from 25 February 2018 to 20 January 2019; d–f) of the dataset. Zonal velocity (a, d), meridional velocity (b, e) and velocity vectors (c, f) are shown. Each velocity vector is defined by the deviation of the zonal velocity from the local-time average and the total meridional velocity. Arrows are scaled such that the distance occupied by 10° in latitude represents a meridional speed of 5 m s⁻¹ and that occupied by 1 h in local time represents a zonal speed of 5 m s⁻¹.