Short communication a conceptual model relating the quasi-biennial oscillation and the tropospheric biennial oscillation

摘要

A survey of the zonal wind throughout the troposphere and the lower stratosphere near the equator is made for the 41 year period of 1958-98. A similar survey of the 500 hPa geopotential height, sea-surface temperature (SST) and tropopause height is also made, except that the survey period for the tropopause height is shorter than 41 years due to unavailability of data. Other than the well-known quasi-biennial oscillation (QBO) feature in the lower stratosphere and the tropospheric biennial oscillation (TBO) feature exhibited by the SST, similar oscillation features are found throughout the whole troposphere by both surveys. Pearson cross-correlation functions and smoothed power spectrums of all meteorological parameters used in the surveys indicate that all these features are statistically significant at the 90-95% confidence level. The Pearson cross-correlation functions are further used to deduce a conceptual model relating the QBO in the lower stratosphere and the TBO feature found in the interannual variability of monsoon pattern at and near the surface of the Earth. The QBO and TBO seem to be interrelated to each other thermodynamically. Thoughts on QBO-TBO connections in this conceptual model are tentative and await full testing.