Sunday, 9 February 2003
Compare of the environment change between Arctic and China during Holocene times
During the 40 years, the variation of temperature in the Svalbard area and Qinghai-Xizang Plateau has the same periods, such as the long period of 13 years, the short period of 2-3 years. With the seasonal variation of temperature, there is a good relation between winter and throughout the year. The interchange between the dry and wet condition in Svalbard area is positively related to that in the northern Plateau while is negatively related to that in the southern Plateau. There was the trend of becoming wetter in the Svalbard area and in the northern Plateau. In the southern Plateau the trend was reverse . The variation of Arctic ice cover area has influence on the temperature and precipitation in subsequent months over China. In addition, it experiences a quasi-biennial low-frequency oscillation and displays some kind of propagation . Here we draw a valuable conclusion about the relationship between the variation of Arctic ice cover area with the Meiyu South of China , and the precipitation of North China in summer. Some evidence provides the link of climate change between Arctic and China over the past 400 years. Both Arctic and china have two colder periods(17th century and 19th century ) and two warmer periods(18th century and 20th century), but the changing tendency is not identical completely. In the 17th century and 19th century temperature in most part of china (except East China, Xinjiang, Tibet ) increased earlier than that of Arctic. In the 18th century the highest temperature appeared earlier about 10 years in Arctic than China. In the 20th century the warmer period of the two places is similar. The periods of temperature change of the two places are identical, being mainly 130-140, 100, and 80 years. Based on that there is a close relationship between lake level and climatic fluctuations in century time scale, we compare the fluctuation of lake level in the last 600 years reconstructed by  with the variation of Arctic temperature reconstructed by a High-Resolution Speleothem 18O Record from SW Ireland. The conclusion is that the fall of Qinghai Lake level was more than 9m in the first half of 18th century, which is lag the warm period of the 17th and is identical to the cold period of the 18th century in Arctic area. In China there were four times of cooling periods during Holocene: New ice age(Άρ)appeared at 7800aBP, new ice age (Άς) at 5300aBP, new ice age(Άσ)at3800aBP, new ice age(Άτ) at 200aBP, which is also named the Little Ice Age . Between Άρand Άςthere was the first warmest period, between Άσ and Άτ was the second warmest period . Such periods are identical to the Holocene Sodium records from Arctic pole . Acknowledgement that this research is supported by National Natural Sciences Funds of China(49971078).