A high-latitude observation of sporadic sodium and sporadic E-layer formation

Abstract

High-resolution radar and lidar measurements of sporadic sodium (Na) and sporadic E(E) layers were made at the Sondrestrom incoherent-scatter radar facility on 11 December 1997. These measurements suggest a causal link between E and Na, supporting the proposed mechanism in which Na ions in the E are neutralized to form the Na. This Na by contrast does not appear to have been formed by the presence of auroral precipitation or ionization, and, in fact, the sodium density is seen to decrease during an auroral event.