Turbulence, namely, irregular fluctuations in space and time characterize fluid flows in general and atmospheric flows in particular. The irregular, i.e. nonlinear space-time fluctuations on all scales contribute to the unpredictable nature of both short-term weather and long-term climate. Quantification of atmospheric flow patterns as recorded by meteorological parameters such as temperature, wind speed, pressure, etc. will help exact prediction of weather and climate and also provide a model for turbulent fluid flows in general. Meteorologists have documented in detail the nonlinear variability of atmospheric flows, in particular the interannual variability, i.e., the year-to-year fluctuations in weather patterns. A brief summary of observational documentation of interannual variability of atmospheric flows is given in the following. The interannual variability of atmospheric flows is nonlinear and exhibits fluctuations on all scales ranging up to the length of data period (time) investigated. The broadband spectrum of atmospheric interannual variability has embedded dominant quasiperiodicities such as the quasibiennial oscillation (*QBO* ) and the *ENSO* (El Nino/Southern Oscillation) cycle of 3 to 7 years^{ 1} which are identified as major contributors to local climate variability, in particular, the monsoons which influence agriculture dependent world economies. *ENSO* is an irregular (3 - 7 years), self - sustaining cycle of alternating warm and cool water episodes in the Pacific Ocean. Also called *El Nino - La Nina*, *La Nina* refers to the cool part of the weather cycle while *El Nino* is associated with a reversal of global climatic regimes resulting in anomalous floods and droughts throughout the globe. It is of importance to quantify the total pattern of fluctuations for predictability studies. Observations show that atmospheric flows exhibit fluctuations on all scales (space-time) ranging from turbulence (mm-sec) to planetary scale (thousand of kilometers-year). The power spectra of temporal fluctuations are broadband and exhibit inverse power law form *1/f ^{B}* where

The authors are grateful to Dr.A.S.R.Murty for his keen interest and encouragement during the course of the study.

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