Anomalous heating of the polar E region by unstable plasma waves 1. Observations

Abstract

With the incoherent scatter facility at Chatanika, Alaska, we have measured electron temperatures of up to 1200°K near 110‐km altitude in the polar E region in the presence of strong electric fields. No classical heat process can account for these high temperatures, which are clearly correlated with the dc electric field strength. We show that the enhancement is most probably caused by the unstable plasma waves known to exist in the disturbed polar E region.