The equatorial stratospheric QBO and geomagnetic activity

MARTA ZOSSI DE ARTIGAS; ANA G. ELIAS

Atibaia, San Pablo

Congreso; 7ma COLAGE, Conferencia LatinoAmericana de Geofísica Espacial; 2004

ALAGE, Asociacion LatinoAmericana de Geofisica Espacial

The quasi-biennial oscillation (QBO) of the zonal wind in the equatorial stratosphere is analyzed in connection to geomagnetic activity as measured by the Dst index. A running correlation between Dst bandpass filtered values, and the equatorial zonal wind at 15, 20 and 30 hPa was estimated. An oscillation of around 11 years can be noticed in the running correlation coefficients, with maximum positive and negative values during maximum and minimum solar activity levels respectively. Taking into account that higher negative Dst values correspond to stronger geomagnetic storms, 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. Considering a possible influence of geomagnetic activity over ozone and atmospheric dynamics, a link between these results, the Northern Polar stratospheric ozone content and stratospheric warming frequency occurrence is suggested.