Geomagnetic activity and the equatorial stratosphere QBO

ANA G. ELIAS; MARTA ZOSSI DE ARTIGAS

Toulouse

Congreso; 10th Scientific Assembly of the International Association of Geomagnetism and Aeronomy; 2005

IAGA, International Association of Geomagnetism and Aeronomy

Geomagnetic activity indices are bandpass filtered and analyzed in connection to the quasi-biennial oscillation (QBO) of the zonal wind in the equatorial stratosphere. A running correlation between the equatorial zonal wind velocity at different height levels in the stratosphere and the filtered geomagnetic activity indices was performed. An oscillation of around 11 years can be noticed in the running correlation coefficients with maximum positive and negative values during minimum and maximum solar activity levels respectively. This means that during maximum solar activity, there is higher (lower) geomagnetic activity during the QBO easterly (westerly) phase. During minimum solar activity this relationship is reversed. With relation to this result, proton flux data and ozone content at high latitudes are analyzed. An influence of geomagnetic activity variations over ozone and atmospheric dynamics through the modulation of energetic particle precipitation is suggested.