Ohmic heating as evidence for strong field‐aligned currents in filamentary aurora

Abstract

A large increase in electron temperature measured in filamentary aurora with the European incoherent scatter radar has been modeled with a one‐dimensional electron transport and ion chemistry code. To account for the observed changes in electron temperature, while also reproducing the measured E region electron density profiles, a source of electron heating is required in addition to local heating from energy degradation of the precipitating electrons. We show that ohmic heating in a strong field‐aligned current can account for the required heat source.