Investigating the future changes in the quasi-biennial oscillation periodicity under climate projections through wavelet analysis

Zonal winds at the tropical stratosphere are fluctuating in a periodic manner, constituting the quasi-biennial oscillation (QBO). This study presents the climatological trend of the QBO amplitude and the change in the QBO periodicity s between 0° and 10°N at 10 hPa level using ERA5 reanalysis data alongside CMIP5 MPI ESM MR under RCP4.5 and RCP8.5 scenarios. Wavelet analysis is applied to reveal the complexity of the QBO. A decrease is expected in the amplitude of the zonal winds according to CMIP5 MPI ESM MR under RCP4.5 scenario. Additionally, QBO periodicity is likely to decrease until 2100 in both scenarios.