Magnetospheric Current SheetA thin layer of electric current flowing in the magnetosphere's equatorial plane. During storms, it thins and intensifies as magnetic energy accumulates in the tail. Its structure reveals how energy is stored and released.: 3D Coherence Structure
Halloween 2003 — Latitude-resolved Moran's IA spatial autocorrelation statistic (-1 to +1). Values near +1 mean neighboring stations show similar perturbations (organized structure). Near 0 means random. Measures whether the magnetic field disturbance has spatial coherence at each latitude. mapped to equatorial L-shellsA coordinate measuring distance from Earth in the equatorial plane, in units of Earth radii. L=1 is the equator surface. L=5.6 corresponds to ~65° latitude. Higher L = further out in the magnetosphere. Named for McIlwain's L parameter. + altitude decomposition
Latitude / L-Shell Coherence Profile
Bar height = Moran's I at that latitude band
Color: green=electrojet-dominated, blue=FAC-dominated
Right axis: L-shell mapping (dipole)
Altitude Profile + Phase Space
Left: I vs altitude (2-layer ChapmanThe Chapman profile describes how solar radiation is absorbed at different altitudes, producing an ionization peak. Two layers: E-region (~120 km, auroral precipitation) and F-region (~300 km, solar EUV). Each altitude's coherence reveals different current systems.)
Blue band: F-region (300km) / Red band: precipitation (120km)
Horizontal: L-shell (equatorial distance). Vertical: altitude. Color intensity = coherence at that (L, alt) cell.
Green = high Moran's I. The current sheet thicknessThe spatial extent (in L-shell) over which the current sheet maintains coherent structure. A thin, coherent current sheet (narrow green band) indicates concentrated energy storage. Broadening suggests disruption or energy release. appears as the width of the coherent band.