The Quasi-biennial Oscillation and annual variations in tropical ozone from SHADOZ and HALOE

[摘要] We examine the tropical ozone mixing ratio perturbation fields generatedfrom a monthly ozone climatology using 1998 to 2006 ozonesonde data from theSouthern Hemisphere Additional Ozonesondes (SHADOZ) network and the 13-yearsatellite record from 1993 to 2005 obtained from the Halogen OccultationExperiment (HALOE). The long time series and high vertical resolution of theozone and temperature profiles from the SHADOZ sondes coupled with goodtropical coverage north and south of the equator gives a detailed picture ofthe ozone structure in the lowermost stratosphere down through thetropopause where the picture obtained from HALOE measurements is blurred bycoarse vertical resolution. Ozone perturbations respond to annual variationsin the Brewer-Dobson Circulation (BDC) in the region just above thecold-point tropopause to around 20 km. Annual cycles in ozone andtemperature are well correlated. Above 20 km, ozone and temperatureperturbations are dominated by the Quasi-biennial Oscillation (QBO). Bothsatellite and sonde records show good agreement between positive andnegative ozone mixing ratio anomalies and alternating QBO westerly and easterlywind shears from the Singapore rawinsondes with a mean periodicityof 26 months for SHADOZ and 25 months for HALOE. There is a temporal offsetof one to three months with the QBO wind shear ahead of the ozone anomalyfield. The meridional length scales for the annual cycle and the QBO,obtained using the temperature anomalies and wind shears in the thermal windequation, compare well with theoretical calculations.

[学科分类] 大气科学