Project No. ????? - Grant Agency of Czech Republic
Duration: 1993-1995
Principal Investigator: Ivanka Charvatova
Geophysical Institute of the Czech Academy of Sciences, Bocni II/1401, 141 31 Praha 4, Czech Republic, Tel.: +42-2-37103 080, Fax: +42-2-71-761549, E-mail: ich@ig.cas.cz
Co-workers: J. Strestik
Aim of the Project: The aim of this project is to provide a substantiated prediction of climate development in central Europe (Czech Republic) for the next 3-4 decades. This prediction is based on the solar inertial motion which can be computed in advance and probably plays the primary role in the chain of solar-terrestrial (ST) phenomena that create, in summarized influence, a natural part of climatic changes. The instrumental solar-terrestrial and climatic time series from the recent centuries have been gradually processed. The solar systemic features in these phenomena have been searched for (such as their extraordinary and repeating behaviour, in steps of 180 years, in the intervals of the ordered motion of the Sun, their behaviour in the last interval of the chaotic motion, their periodicities, etc.) to understand their relations to solar inertial motion as well as their mutual relations.
Employing the solar systemic approach, the parts of the two influences, natural and anthropogenic, in climatic changes could be distinguished and the threat of enhanced greenhouse effect due to anthropogenic gases could be evaluated.
Major Results:
1. Long-term trends in surface air temperature in central Europe. The time series of surface air temperature in central Europe (17531980) was established on the basis of 13 point series. Its long-term maxima which are approximately at the same height occurred about 1760 and 1940. The long-term minimum was revealed near 1840 and the temperature was about 0.8oC lower there compared with the long-term maxima. The long-term maxima coincide with the central decades of the intervals of the ordered solar motion. The instrumental data from North America, which we also processed, confirmed this temperature trends since 1820) (Charvatova & Strestik, 1994a).
2. The behaviour of ST-periodicities in relation to solar motion. Spectral analyses of the solar-terrestrial (climatic) time series have been carried out. If we compute from the whole series, the dominant 11-yr period in the solar activity spectrum has not a corresponding response in the temperature spectrum. The significant periods of 12.8, 10.3 and 7.8 years corresponding to the significant solar systemic periods have been found. The same periods have also been detected in the individual point series from which the temperature series of central Europe has been established. Similar periods have also been revealed in volcanic and geomagnetic activities.
Spectral analyses in the partial intervals corresponding to two types of the solar motion showed that the periodicity pattern within 7 and 15 years of solar activity, geomagnetic activity and surface air temperature appears to be changed in accord with the changes of solar motion during its basic 180-yr cycle: The ST-periodicity pattern in all the cases recurs in both the ordered intervals and the significant periods of 1214 years, 10 years and 7.48.2 years were detected there. For all the phenomena, this periodicity pattern is different in the other intervals of chaotic the motion. The patterns of surface air temperature spectra are similar rather to the patterns of solar motion spectra than to the patterns of solar activity spectra. (Charvatova & Strestik, 1994b)
3. The relations between solar motion and volcanic activity. The time series of volcanic index AI (Acidity Index, 15001972) which has a nearly instrumental character and summarizes volcanic activity of the Northern Hemisphere (together with its two modifications AI1 and AI2 considering the geographical positions of the respective volcanoes) have been processed.
The exceptional pattern of volcanic activity ("noise" character, the absence of huge volcanic events) which recurs after 180 years in coincidence with the intervals of the ordered motion of the Sun (15551600, 173485, 191364) was demonstrated by means of statistical characteristics. This indicates a possible influence of the Solar System as a whole on volcanic activity of the inner planet Earth (Charvatova, 1994b).
Fig. 1. One of the statistical characteristics (ratios of variances) describing the behaviour of volcanic activity in relation to solar inertial motion. The Acidity index since 1510 has been processed (after removal of long-term trends). The solid line represents the ratios of variances of the individual 45-yr subintervals since 1510 to the variance of the interval of the ordered solar motion (191560). The ratios are close to 1 in the very intervals corresponding to the previous ordered intervals (173580 and 15551600) and are different in the other intervals where the Sun moved chaotically. The significance level for p/2 0.005 (2.17) is plotted. The dashed line represents the ratios of variances of the 15-yr subintervals. Their persistence only in the ordered intervals is revealed. The triangles denote the centres of the intervals where the motion of the Sun is ordered (for details see Charvatova 1994c).
4. Trends and periodicities in precipitation. The longest continuous precipitation series from Europe have been processed. Only very slight systemic trend during the last 100 years or long-term periodicity with a period of about 200 yr has been detected. Some periods around 63, 48, 38, 29 and 26 years, corresponding to the higher harmonics of the basic 180-yr cycle, seem to be significant (Strestik 1994).
5. Conclusion. Until about 2040, the motion of the Sun will be chaotic and similar to that of the second half of the 19th century. Analogically to the previous situation, lower solar activity, occurrence of huge volcanic events and lower surface air temperature (maybe up to the turn of the century level) could be expected in the next decades. The ST-periodicities within 7 and 15 years could turn into the chaotic D2-type.
The results support the view that climatic changes could be caused above all by natural variability.
Publications:
Charvatova, I., 1994a. Solar-terrestrial and Climatic Variability during Recent Millenia in Relation to Solar Inertial Motion, Journal of Coastal Research, special issue No. 17 (Holocene Cyclic Pulses and Sedimentation), 72-83.
Charvatova, I., 1994b. Volcanic Activity since 1600 in Possible Relation to Solar Inertial Motion, In: Contemporary Climatology (Ed. by R. Brazdil and M. Kolar), Brno, August 15-19th, 1994, 130-135.
Charvatova, I., 1994c. Repeating Behaviour of Solar and Volcanic Activities in the Ordered Intervals of Solar Inertial Motion, In: Proc. of Workshop PAGES: Manifestations of Climate at the Earth's Surface at the End of the Holocene (Eds. E. Ruzickova and A. Zeman), Kolin, October 13-14th, 1994, (in press).
Strestik, J., 1994. Some Periodicities in European Precipitation Series, In: Proc. of Workshop PAGES: Manifestations of Climate at the Earth's Surface at the End of the Holocene (Eds. E. Ruzickova and A. Zeman), Kolin, October 13-14th, 1994, (in press).
Charvatova, I. & Strestik, J. , 1994a. Contribution of long-term natural changes to the recent global warming. Proc. of the Scientific Conference " Contemporary Climatic Changes ", Szczecin, May-June 1993.
Charvatova, I. & Strestik, J., 1994b. The Solar Systemic Features in ST-phenomena and Surface Air Temperature during the Last Centuries, In: Contemporary Climatology (Ed. by R. Brazdil and M. Kolar), Brno, August 15-19th, 1994, p. 136-141.
Charvatova, I. & Strestik J., 1994c. Variability of Periodicity Pattern within 7 and 15 years in Solar-terrestrial Phenomena and in Surface Air Temperature during the Last Three Centuries, In: Scientific Activities of Prof. Gorczynski and their Continuation, Torun, Poland, p. 30-32.
Charvatova, I. & Strestik J., 1995. Long-term Changes of the Surface Air Temperature in Relation to Solar Inertial Motion, Climatic Change, (in press).
Papers presented at international conferences:
Charvatova, I. & Strestik, J., 1993. Instability of periodicities in surface air temperatures during the last 240 years. Presented (poster) at XVIII. Assembly EGS, Session ST-13, Wiesbaden, May, 1993.
Charvatova, I. & Strestik, J., 1993. Long-term periodicity of volcanic activity. Presented (poster) at XVIII. General Assembly EGS, Session ST-13, Wiesbaden, May, 1993.
Charvatova, I., 1994. The 178.7 and 2160-yr cycles in Solar Motion related to solar variability. Presented (orally) at XIX. General Assembly of EGS, Session ST5, Grenoble, April, 1994.
Charvatova, I. & Strestik, J., 1994. Solar systemic features in ST and climatic phenomena. Presented (orally) at XIX. General Assembly of EGS, Session ST5, Grenoble, April, 1994.
International Cooperations:
Department of Climatology, Copernicus University, Torun, Poland