The quasi-biennial oscillation of water vapor in tropic stratosphere

The Quasi-Biennial Oscillation (QBO), the most interannual variations of tropic stratospheric water vapor are investigated by the HALOE data from 1993 to 2002. There are three centers of water vapor QBO located in upper, middle and lower stratosphere respectively. The simulation results from model SOCRATES3 indicated that the QBO forcing of tropical zonal wind would induce three pairs of residual circulations, and the dynamic transports play an important role in the three QBO centers of water vapor. The QBO of temperature could control the chemical production of water vapor in the middle stratosphere. On the other hand, the temperature s QBO had an important effect on the water vapor condensation in the lower stratosphere.