冰期天文理论是运用地球轨道偏心率、地轴倾角和地转轴进动的3种参数的变化幅度与周期来解释上新世-第四纪期间冰期-间冰期交替变化的一种理论．该理论1842年由Adhemar提出，经过Croll发展到Milankovitch最终完成，经历了整100年的时间．上世纪60年代开始，深海、黄土、冰芯等大量的地质记录都揭示出3种周期变化，证实冰期天文理论的正确性，同时也对冰期天文理论带来了一些概念上的修正．但是， Berger 计算的天文曲线至少从6 Ma以来展示同一规律的变化，然而地质记录却显示清晰的分段响应模式：41 kyr的地轴倾角周期在5.3～1.4 Ma期间一直是记录曲线的主要特征；北半球冰川作用只是在2.7 Ma BP才开始大规模出现；0.8 Ma开始100 ka周期转变为主要周期，称之为中更新世转型（ MPT）．还有：11阶段和全新世是2个偏心率很低的时期，但记录中却是冰期-间冰期振幅最大的时期，即大的间冰期为何出现于低偏心时期；由间冰期进入冰期比由冰期进入间冰期时来得迅速，意味大冰盖建造需要很长的时间，而消融则比较迅速．这些都是冰期天文理论本身不能解释的问题，正在由地球响应系统的研究来探索答案．%The astronomical theory of ice age provides an update solution to Quaternary glacial-interglacial cycles based on the long-term variations of three earth ’ s orbital parameters , eccentricity , obliquity and precession .This theory had been under modification over one hundred years since it was suggested by Adlhemar in 1842 , developed by Croll and finished by Milankovitch in 1941.Since 1960s, numerous geological records from sea , loess and ice core have been exhibiting the three different cycles of 100kyr, 41kyr and 21kyr, demonstrating the validity of the theory , and meanwhile , brought some revisions to the theory .However , there are still a lot of brainteasers between the geological records and the theory that needs to resolve .The calculation by A .Berger indicates that the curve of insolation controlled by the three orbital parameters exhibits similar changes for at least past 6 Ma, but the curves of geological records present piecewise response .For example , obliquity of 41 kyr cycle was dominant between 5.3~1.4 Ma;Onset of the major northern hemispheric glaciation started up at approximately 2.7 Ma;100 kyr periodicity of eccentricity substituted 41kyr periodicity of obliquity around 0.8 Ma, which is called the Event of Middle Pleisto-cene Transition.In addition, why the most prominent glacial-interglacial transition occurred at time of minimal ec-centricity of Stage-11 and Holocene;How to explain the slow transitions from interglacial to glacial and the quick transition from glacial to interglacial in 100 kyr cycles , and so on .Those questions associated with the response mechanism of the complex earth system to the orbital forcing , and were warmly discussed in the past decade .
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