HIGH RESOLUTIONAL RECONSTRUCTION OF TROPICAL ENVIRONMENTS AND EVALUATION OF LINKAGE BETWEEN HIGHLATITUDE ICEASHEETSAND LOALATITUDE ENVIRONMENTS

赤道西太平洋的特征是西太平洋暖池(WPWP)，它是世界上开放海洋水温最高的，从100°E到180°的表面积约为2.0×107平方公里，是地球上最大的单片暖水。这片靠近新几内亚的狭长海域的温度一直高于28℃，比其他赤道地区高出约2至5℃。利用帝汶海的MD05-2970资料进行了从现代到220KYR的高分辨率研究，以了解澳大利亚季风的演变，因为以前的工作认为冰期澳大利亚季风要小得多。我们的浮游有孔虫氧同位素组成范围从最后一次冰期最大值的-1.0permil到全新世的-2.8permil，这与之前在附近地区报告的记录一致。研究表明，倒数第二次冰盛期和最后一次间冰期的氧同位素结构相似。而Makasser海峡的氧同位素记录表明，最后两次冰盛期和间冰期的氧同位素记录分别为-1.0permil和-4.0permil。氧同位素的任何差异都可归因于由于水文差异而引起的海水氧同位素的变化。这些结果表明，在冰川时代，澳大利亚夏季风没有今天那么强烈，导致两者之间的盐度差异。

The equatorial western Pacific is characterized by the Western Pacific Warm Pool (WPWP) which has the highest open-ocean water temperatures in the world and a surface area of approximately 2.0×10^7 km^2 extending from 100°E to 180, the largest single expanse of warm water on our planet. This swath of ocean near New Guinea has a temperature consistently higher than 28℃, about 2 to 5℃ higher than that of other equatorial regions. The temperature and geographic extension of the WPWP fluctuate from year to year and have a relation with ENSO (El Nino - Southern Oscillation) events.High resolution study from the modern to 220 kyr was conducted by using MD05-2970 obtained from Timor Sea to understand the evolution of the Australian monsoon since previous works proposed much lesser Australian monsoon during the ice ages. Our planktonic foraminiferal oxygen isotopic compositions range from -1.0 permil for the last glacial maximum to -2.8 permil for the Holocene which is consistent with the record previously reported from nearby locations. The present study showed the similar structures of oxygen isotopes between the penultimate glacial maximum and the last interglacial. However the oxygen isotope record obtained from the Makasser Strait indicated -1.0 permil and -4.0 permil respectively for the last two glacial maxima and the interglacials. Any discrepancies in the oxygen isotopes are attributable to changes in the oxygen isotopes of seawater due to the hydrological differences. These results shows that Austral summer monsoon was not as strong as today to create salinity differences between the two during the glacial times.