SBIRS is a constellation of four satellites parked in geosynchronous orbit above the equator, plus two additional sensors hosted on spy satellites that fly over the North Pole.
Scientists have known for about 30 years that the additional water would flow toward the Equator from the poles, adding mass to the planet's middle and a bit of drag to its rotation.
Additional relaxing incisions were made at the equator level circumferentially.
MAGDAS includes an additional chain of stations along the geomagnetic dip equator.
This latitudinal bias is due to the influence of position (distance from equator; Table 1) in the PCA (Additional file 3).
See also movie (Additional file 1) Fig. 5 a Hovmoller diagram at the equator for thickness anomaly (color shading, normalized) with the blue and red lines indicating the phase speeds of equatorial Kelvin waves and long Rossby waves, respectively.
The parameters s and Jdc are determined by least-squares inversion of Eq. (32), with the additional constraint that the left and right hand sides of that equation must agree at the magnetic equator (θ = π/2).
A higher occurrence rate of the emissions in the dawn sector and their confinement to the geomagnetic equator, pointed out in previous studies, are confirmed and described with additional details.
An additional third maximum, which can be seen in modelled wind shear around the equator, is only weakly visible in ES due to the horizontal orientation of the magnetic field lines at Northern Hemisphere low latitudes.
Principal component (PC) 1 explained 64% of the variation and loaded most heavily on size (area, perimeter, latitudinal range) and permeability (shape); PC2 explained an additional 19% of the variation and loaded most heavily on position (distance from equator) and permeability (fragmentation; Additional file 3).
