Wednesday, 16 January 2002
The properties of a strange attractor reconstructed from the time series of tropospheric mean temperature
The correlation dimension and Lapunov coefficients for a dynamic system constructed on the base of tropospheric mean temperature time series will be presented. The calculations proved that the attractor is strange and his geometrical structure is fractal. The attractor’s strangeness results from the existence of positive values of the Lapunov coefficients. Based upon these results the estimated time of the dynamic system prediction is 13 days. On the base of archive of 25 years of 500 hPa surface geopotential measurements one constructed a “climatic” strange attractor. Its correlation dimension is non-integer number. The analysis of the results shows a large jump in the values of correlation dimension. It may be treated as a some kind of discontinuity. That fact is observed in the short period 31.12.1975-31.12.1976. This process can be interpreted by climatologists as a phenomenon of strong bifurcation occurring. The value of correlation dimension rapidly fell down from 8.8 to 6.8. The attractor decreased to the smaller dimension space. The collapse happened. The dynamic system refers to that attractor suddenly lost two degrees of freedom. It is equivalent to the large disturbance in the scale invariant of the dynamic system. In our interpretation it means the climatic anomaly occurred at that time.