Using the independent series of the Reconstructed (Observed) Northern Hemisphere Temperature Anomalies ( R(O)NHTA ) it is possible to verify the physical-empirical Model of the NHTA and to check the model’s possibilities of a long-term prediction.

Confidence levels of the correlation for 200-year intervals (95%, 99% and more) show the reliability of the prediction in the past for 450 years, so we can predict the future natural variations of NHTA at least for 150 years for 1964-2100 interval.

The model can be used also to detect the internal aperiodic climate signal due to greenhouse gases. The difference between the Reconstructed/Observed NHT and variations related with MNHTA equals the sum of random and systematic aperiodic components of solar and terrestrial processes. Beginning from 1900 the internal aperiodic climate signal (IACS), related with greenhouse gases, detected resolutely by averaging the difference, mentioned above, over 50 years to reduce anomalies from the random components. The same signal detected from 1925 in the case of 7-year averaging.

Figure. Modelled Northern Hemisphere Temperature Anomalies, MNHTA, (Berry, (Berri), 2001), Reconstructed (Observed) R(O)NHTA (Mann et al., 1998), Northern Hemisphere Temperature Anomalies (NHTA) and Internal Aperiodic Climate Signal (ISCS). MNHTA(PDI) - Modelled NHTA on the Proxy Data Interval, 1659-1964, R(O)NHTA - Reconstructed (Observed) NHTA averaged over 7 years; CORREL - correlation of the R(O)NHTA with the Modelled NHTA, the time axis denotes the center of a 200-year moving window; CL99% (r = 0.41), 95% (r = O.31), 90% (r = 0.24) - Confidence Levels for correlation in 200-year interval between R(O)NHTA and MNHTA, IACS = R(O)NHTA - MNHTA - Internal Aperiodic Climate Signal (50 year lowpass).

Berry (Berri) B. L., 2001: Variations of climate and soil temperature regime in the past millennium and their prediction for 200 years. Internet Journal of Geocryology, V.3, p.1 - 13, (in Russian).