QBO is a quasi - biennal oscillation discovered by Ebdon et al. in 1960. This is the phenomenon of atmospheric oscillation in the wind zone of tropical the upper atmosphere that changes from East to West and reverses with period of 02 years (~ 28 - 29 months). QBO influences on the weather and climate over the tropical Pacific, especially combined with ENSO. El Nino phare and QBO are more closely correlated than La Nina phare. QBO usually spreads slowly in the La Nina phase in the first 4 months, but QBO spreads more quickly in the El Nino phase in the last 4 months of the year.
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