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通过古里雅冰芯中δ~(18)O与微粒含量的研究,恢复了末次间冰期以来青藏高原大气粉尘和环境变化的历史。记录显示,青藏高原在末次间冰期时处于低粉尘值,105 ka时高原上的粉尘浓度开始升高。约75 ka左右进入冰期后,微粒浓度大幅度剧增,并在末次冰期早期(MIS 4阶段)达到了最高水平。在末次冰盛期,古里雅冰芯中微粒含量的增加并不显著,与南极和格陵兰不同。在轨道时间尺度上,温度和北半球高纬夏季太阳辐射与微粒记录都有良好的相关性,但也存在幅度和相位上的差异。青藏高原及其外围山地的冰芯记录反映的是中亚粉尘源区以及粉尘传输起始阶段的变化,而格陵兰冰芯记录反映的是粉尘最终的沉积状况,二者的意义是不同的。
Through the study of δ 18 O and particle content in the Guli ice core, the history of atmospheric dust and environment in the Qinghai-Tibet Plateau since the last interglacial period has been restored. The records show that the Qinghai-Tibet Plateau was at a low dust level during the last interglacial period and the dust concentration began to increase on the plateau at 105 ka. At about 75 ka into the ice age, the particle concentration increased sharply and reached the highest level in the last glacial (MIS 4). During the last glacial expanse, the increase of microparticles in the Guli ice core was not significant, unlike the Antarctic and Greenland. On the orbital time scale, there is a good correlation between temperature and summer solar radiation in the northern hemisphere and particle records, but there are also differences in amplitude and phase. The ice core records of the Qinghai-Tibet Plateau and its surrounding mountains reflect changes in the source regions of dust in Central Asia and the initial stages of dust transmission, whereas the Greenland ice core records reflect the eventual deposition of dust, both of which have different meanings.