Fig. 3

Longitude and latitude variations of hmM2, NmM2, and Hn. a–c present the gridded mean hmM2, NmM2, and Hn, respectively; d–f are standard deviations of the gridded hmM2, NmM2, and Hn, respectively; g–i show the residual hmM2, NmM2, and Hn, respectively, after removing zonal averages; j–l are percentage longitude variations of hmM2, NmM2, and Hn, respectively, with respect to zonal averages