摘要：The irregular characteristics of E and Es layers are studied with data from 1995 to 2002 observed by a Digisonde Portable Sounder-4 (DPS-4) ionosonde at Zhongshan Station, Antarctica. Because they have much similar characteristics with Polar Mesosphere Summer Echoes (PMSE), two criteria are proposed to study PMSE at MF and HF bands in Southern hemisphere. The phenomena of irregular E and Es layer are called as PMSE-like or Polar Mesosphere Summer Echoes-Es (PMSE-Es) here. The occurrence rate variations of PMSE-Es show similarity to those of PMSE at multi-scales, such as seasonal, diurnal, and semidiurnal variation. Finally, the discrepancies between diurnal, semidiurnal and seasonal variation between PMSE and PMSE-Es are discussed respectively.
