A strong ~11-min-long surge of the lobe reconnection was observed during a substorm on the tailward side of the near-Earth neutral line. In the southern lobe near the reconnection separatrix the MMS spacecraft observed short-duration earthward electron beams providing the local Hall current, tailward propagating Alfven wave (AW) bursts with Poynting flux up to 10−4 W/m2, and large-amplitude E field spikes (e-holes) and low hybrid waves. The reconnection surge was accompanied by substorm current wedge formation and fast poleward expansion of auroral bulge-related westward electrojet in the conjugate ionosphere. During its meridional crossing above the expanding bulge the Metop-2 spacecraft observed an intense energetic precipitation spike near the expected X line foot point and confirmed the dipolarized character of magnetic field lines inside of the bulge. Globally the observed average reconnection rate (<Ey > ~3.3 mV/m) was sufficient to produce the magnetic flux increase in the bulge, associated with observed fast poleward expansion (about 6° latitude in 5 min).
QC 20191017