  In this study we use high-quality convection data from the Electron Drift
Instrument on board Cluster to investigate how near-Earth tail activity affects
the average convection pattern in the magnetotail lobes when the interplanetary
magnetic field has a dominating east-west (B$_{y}$) component. Two different
proxies have been used to represent different levels of reconnection in the
near-Earth tail: The value of the AL index and the substorm phases identified
by the Substorm Onsets and Phases from Indices of the Electrojet algorithm. We
find that the convection changes from a dominantly Y$_{GSM}$direction, but
opposite in the two hemispheres, to a flow oriented more toward the plasma
sheet, as the north-south component of the convection increases when
reconnection enhances in the near Earth tail. This result is consistent with
recent observations of the convection in the ionosphere, which suggest that the
nightside convection pattern becomes more north-south symmetric when tail
reconnection increases. This is also supported by simultaneous auroral
observations from the two hemispheres, which shows that conjugate auroral
features become more symmetric during substorm expansion phase. The reduced
asymmetry implies that the asymmetric pressure balance in the lobes is altered
during periods with strong reconnection in the near-Earth tail.
