AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Meteorological phenomena in thermosphere11/1/2023 ![]() In recent years, the thermosphere has also been found to be sensitive to meteorological forcing from the lower atmosphere. The thermosphere is known to respond closely to solar forcing at various timescales ranging from the solar cycle to a few minutes during solar flares (e.g., Liu et al. This region is not only important for satellite operations because of air drag, but also scientifically important for vertical coupling between the upper and lower atmosphere because of its high sensitivity to both solar forcing and lower atmosphere forcing. The thermosphere is the upper part of the Earth’s atmosphere, occupying the region between about 100–600 km altitude. Therefore, we conclude that the 28-month periodicity in thermospheric density may be caused by both QBO and solar radiation, whereas the 64-month periodicity possibly arises mainly from ENSO processes, with little/small contribution from solar radiation. Further examination reveals that the coherence between QBO and the faster mode is significantly influenced by their common coherent variation with the solar flux, while high coherence between the slower mode and ENSO is much less contaminated. The slower mode bears high coherence with the ENSO during 1982–2012, while the faster mode is found to vary coherently with the QBO around 1972, 19. Wavelet analysis reveals two major modes of the thermosphere inter-annual oscillation, with the slower mode having an average period of ~64 months and the faster mode of ~28 months. Using a 46-year-long dataset of the thermospheric density during 1967–2012, we examined the inter-annual variability in the thermosphere at 400 km and its potential connection to El-Nino Southern Oscillation (ENSO) and stratospheric Quasi-Biennial Oscillation (QBO).
0 Comments
Read More
Leave a Reply. |