Low-latitude mesospheric signatures observed during the 2017 sudden stratospheric warming using the fuke meteor radar and ERA-5

Abstract

The signature of the low-latitude mesosphere response to the February 2017 minor sudden stratosphere warming (SSW) was detected using the observations of a meteor radar at Fuke (19.5°N, 109.1°E) a low-latitude station in China and ERA-5 data. Radar detected the zonal wind reversal in the mesosphere three days before the SSW event, whereas the ERA-5 does not reproduce the mesospheric wind response at low-latitudes during the 2017 SSW and large discrepancies are found between the mesospheric zonal winds derived from the Fuke radar and ERA-5. The quasi oscillatory pattern was noted in the meridional winds before the SSW event, afterward, the northward winds are significant. We observed the existence of 20–28-day planetary waves (PWs) in the Fuke meteor radar measured mesospheric zonal winds before the SSW and the 2-12-days period PWs before and after the SSW in the meridional winds. The zonal structure and periodicity of the PWs have been verified with the other meteor radar at the Indian tropical station Tirupati (13.63°N, 79.4°E). However, ERA-5 does not capture the PW activity in the mesosphere as radar. The similarities and dissimilarities among the different techniques have been discussed. Therefore, the present study re-emphasizes the strong response of the low-latitude mesosphere to the 2017 minor SSW in a manner similar to the major SSW event.