Premium
Seasonal and solar cycle variations in high‐ latitude thermospheric winds
Author(s) -
Aruliah Anasuya L.,
Rees David,
Steen Ake
Publication year - 1991
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/91gl02240
Subject(s) - equinox , thermosphere , latitude , atmospheric sciences , solar cycle , environmental science , seasonality , climatology , ionosphere , solar maximum , noon , evening , geology , solar wind , physics , geodesy , astronomy , quantum mechanics , geophysics , statistics , mathematics , magnetic field
Thermospheric wind measurements have been collected systematically every winter for over nine years from a high‐latitude site at Kiruna, Sweden (67.8°N, 20.4°E). The database contains 1242 nights of data collected with a Fabry‐Perot Interferometer (FPI), perhaps the largest single‐site database of thermospheric winds. This analysis shows a marked seasonal and solar cycle variation. Particularly at high solar activity, sunward winds of the evening period (16–20 UT) are more than 50% stronger at Spring than at Autumn equinox. This large asymmetry in the behaviour of high‐latitude thermospheric winds at spring and autumn equinox has not yet been predicted by model simulations.