2500多年来的太阳活动与温度变化

THE SOLAR ACTIVITY AND AIR TEMPERATURE FLUCTUATION IN RECENT 2500 YEARS

利用Schove推算出的2500多年太阳黑子极值出现的年份得到了2500多年来的太阳黑子周期长度，将其与北半球部分地区温度对比，发现太阳黑子周期长时北半球温度低，太阳黑子周期短时北半球温度高；快周期持续时间越长暖期持续时间也越长，反之亦然。最后，利用太阳黑子周期长度和万年尺度的温度变化趋势拟合了2500多年来的温度变化，它与我国温度和极区温度有一定的可比性。

Friis-Christensen and Lassen (1991) have reported a good correlation between the variable period of the 11 -year sunspot cycle and the mean Northern Hemisphere land surface temperature from 1865 - 1985. According to them, the raw minimum to minimum and maximum to maximum cycle length series from 522B.C. to present were derived by using the basic sunspot data given by Schove. Then, the two wbes were combined into a single series (SCL, for short). Over the 2500 years, the mean value of SCL is 11.07yr. Power spectrum analysis of the 2 500yr SCL record yielded 200, 76.9, 50, 41.6, 22, 11.1 and 5.6yr significant periodicities. The 200- and 76.9-yr periodicities may reflect the well-known century time scale solar period. After 15 points running mean, 10 short cycle stages and 9long cycle stages were identified. Moreover, three maxima and six minima stageS of solar activity revealed from 14C are more or less in line with the short and long stageS of SCL.So, the SCL is also a good parameter of solar activity on century time scale.The Zhu's temperature curve, which was reconstructed by S. Hamed and Gong Gaofa,the δ18O curve in the Guliya ice core on the west part of Tibetan Plateau) and Greenland ice sheets were ed to compare with SCL Those three series may represent the temperature fluctuation in East China, Tibetan Plateau and polar region, respectively. If we look into the results in some detail, one can find some interesting results.Firstly, the longer the SCL is, the colder the earth's temperature is. Most short (long) episodes of SCL are coincide with the warm (cold) stages of earth's temperature.The corresponding ratios are the Zhu's temperature: 14/ 19, the Guliya ice core δ18O: 12 /15,Greenland ice sheets δ18O: 14 /15, respectively. Therefore, the temperature fluctuation in the polar region is very sensitive to the solar activity.Secondly, the longer the short (long) periods of SCL lastal, the longer the warm (cold) stages of earth's temperature maintained. Nearly all the center years of short (long)periods of SCL are ahead of the center years of warm (cold) stages of earth's temperature.Comparing the SCL with the Zhu's temperature, the Guliya ice core and Greenland ice sheets δ18O curves, the ahead ratios are 8/8, 11/12, 10/12 and the mean led years are 10.6,25, 12.5yr, respectively.Thirdly, the SCL can describe the subtle temperature fluctuation of China. Although it was relatively warm during 300~44BC, cold climate occurred in Qin dynasty and center Han dynasty, While in the same bine, the SCL was relatively long. It was very cold in 200 ~ 500A.D., especially in 280 ~ 289A.D., and the average SCL in 247 ~ 290A.D.was 12.5yr, which was 1.5 year longer than the mean value of SCL in recent 2 500 years.Moreover, there was a col 19th century in China, nevertheless, a warm decade occurred in 1850's. The mean SCL during 1829 ~ 1848 was 9.3yr, characterized by the shortest periods.After interpolate the SCL into annual series, the correlation coefficient is -0.762 with the SCL ahead the Chiners annual air temperature (CAAT) by one year over 1875 ~1988. Then a regression equation was made between CAAT and SCL. It can explain about 57.8% of the variance of CAAT. Finally, basing on the regression equation the temperature trend on 10 000yr time scale, an air temperature curve in China from 2 500 yr to the present was fitted. After flirt the fitted temperature, the correlation coefficients of the fitted series with the Zhu's temperature and the Greenland ice sheets δ18O series are 0.441and 0.459 respectively. They are both higher than the α=0.001 significant level.Therefore, the variations of SCL (solar activity) are probably responsible for the temperature fluctuation in recent 2 500 years, but other factors such as the volcanic aerosol and greenhouse gases may also contribute to the climatic changes during the last two and a half millennium.