LOW LATITUDE NEGATIVE BAYS

It is shown that the eastward current flowing along the auroral zone in the afternoon sector does not generate the westward return current in the middle and low latitudes, but spreads to the equator. It is shown also that the so-called 'negative bay' which had been thought to be due to the westward return current is caused by the simultaneous growth of the asymmetric storm-time radiation belt (the ring current). The present study suggests a very close relationship among the auroral substorm, the polar magnetic substorm and the formation of the storm-time radiation belt (the ring current). © 1968.