Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM11] Effects of recurrent storms: from the heliosphere to the atmosphere

Thu. May 24, 2018 10:45 AM - 12:15 PM 303 (3F International Conference Hall, Makuhari Messe)

convener:ALEXEI DMITRIEV(Institute of Space Science, National Central University, Jungli City, Taiwan), Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University), Chairperson:Miyoshi Yoshizumi(ISEE, Nagoya University)

12:00 PM - 12:15 PM

[PEM11-06] Solar cycle variations in the mesopause temperature and F2 peak electron density

*Irina Medvedeva1, Konstantin Ratovsky1 (1.Institute of Solar-Terrestrial Physics SB RAS)

Keywords:solar and geomagnetic activity, mesopause temperature, peak electron density

We present the results of analysis of seasonal and year-to-year variations in the mesopause temperature (Tm) in current 24th solar cycle. The analysis is based on 2008-2017 dataset obtained from spectrometric measurements of the OH emission (834.0 nm, band (6-2)) at the Geophysical Observatory of the Institute of Solar-Terrestrial Physics (51.8 N, 103.1 E, Tory). The measurements are carried out in nighttime with temporal resolution 10 minutes. OH rotational temperature is determined with 1-2 K accuracy and corresponds to the atmosphere temperature at the emission layer height (the mesopause region).
Using harmonical analysis, we obtained mean temperatures, amplitudes and phases of annual harmonics for the period 2008-2017. These values were compared with solar and geomagnetic activity variations.
The year-to-year changes of the mesopause temperature and peak electron density (NmF2) variabilities caused by manifestations of the activity of atmospheric waves were investigated. The patterns of the NmF2 and Tm variability in different period ranges were analyzed and compared. The period range included day-to-day (periods T > 24 hrs) and tidal (8 hrs < T < 24 hrs) variations, as well as variations in the internal gravity wave period range (T < 8 hrs).
Data on F2 peak electron density NmF2 were obtained from Irkutsk DPS-4 Digisonde (52.3 N, 104.3 E). We revealed that annual mean NmF2 variability agrees well with geomagnetic activity only for daytime day-to-day variations. There is no clear correlations between year-to-year patterns of Tm and NmF2 variabilities.
The reported study was funded by RFBR and MOST according to the Russian-Taiwanese joint research project 18-55-52006 MHT_a. Experimental data recorded by the Angara Multiaccess Center facilities of ISTP SB RAS were used.