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

摘要

High-resolution radar and lidar measurements of sporadic sodium (Na-s) and sporadic E (E-s) layers were made at the Sondrestrom incoherent-scatter radar facility on 11 December 1997. These measurements suggest a causal link between E-s and Na-s, supporting the proposed mechanism in which Na+ ions in the E-s are neutralized to form the Na-s. This Na-s, 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. [References: 14]