Open Access

Observations of mesospheric sporadic sodium layers with the MU radar and sodium lidars

  • Hirohisa Miyagawa1, 4Email author,
  • Takuji Nakamura1,
  • Toshitaka Tsuda1,
  • Makoto Abo2,
  • Chikao Nagasawa2,
  • Takuya D. Kawahara3,
  • Keiji Kobayashi3, 5,
  • Tsukasa Kitahara3 and
  • Akio Nomura3
Earth, Planets and Space201451:BF03353237

DOI: 10.1186/BF03353237

Received: 17 August 1998

Accepted: 4 July 1999

Published: 26 June 2014


The dynamical structure of the atmosphere around the sporadic sodium layer at mid-latitude (35°N) below 100 km was studied by simultaneous observation with the MU radar at Shigaraki (34.9°N, 136.1°E), and two Na lidars at Shigaraki and in Hachioji (35.6°N, 139.4°E). In the lidar data, fifteen Nas (sporadic sodium layer) events were detected. Wind shear, temperature, and stability indices, at around the time and height of Nas were observed with the MU radar. Strong total wind shear correlated well with Nas, especially when sporadic Es did not accompany. However, no other clear correlations, such as correlations with temperature etc., were found. The result is similar to the report of the lidar observations in Hawaii during the ALOHA-93 campaign (Qian et al., 1998), and suggests a similar generation mechanism between 20°N and 35°N.