Reconstructions of the Southern Oscillation and Pacific Sea Surface Temperature for the Last 500 Years

In this paper, a canonical correlation technique has been used to reconstruct the seasonal index of the Southern Oscillation and seasonal Pacific SST from the dryness/wetness in China for the last 500 years. About 40 percent of the SO variance during the calibration period of 1913—1973, and about 20 percent of the variance for an independent period of 1852—1912 have been caliberated and verified, respectively. In the reconstrucion of the Pacific SST, about 60 percent SST variance has been caliberated in the equatorial eastern Pacific areas and the estimate value has been efficiently verified over 100 years. It shows that the past ENSO events can be reconstructed in certain extent by using dryness/wetness data in China. It is found that ENSO events not only has apparent periodicity, but also has about 250 years stage change. Both SO and SST have the well-known 2—7 year periodicities, besides, SO has 10.6 year period and SST has 25—28.5 and 100 year periods which related with the solar activities. It is also found that the low SOI events are estimated to be less frequency during the 18th, 19th and the early 20th centuries than the later 15th, 16th, 17th and later 20th centuries, and that the frequent (rare) occurrence of the low SOI events mentioned above corresponds with the climatic cold (warm) period, and that the dryness (wetness) period in China is related to the cold (warm) East Pacific and warm (cold) West Pacific