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通过覆盖黄土高原的30个黄土-古土壤剖面磁化率的测量,绘制了倒数第二冰期(约150kaBP)、末次间冰期(约130～74kaBP)、末次冰期间冰段(约59～24kaBP)、末次冰期极盛期(约18kaBP)及全新世气候适宜期(约9kaBP)共5个特征气候期的磁化率等值线略图。以末次冰期极盛期黄土的磁化率作为风成粉尘的原始磁化率,相对于这个本底值的磁化率增量可作为夏季风气候活动在相应地区的指示及其相对强度。据此,初步恢复了由磁化率等值线所反映的各个时期夏季风气候的空间格局,并估计了夏季风平均锋面的活动范围及其北界的可能位置,从而粗略地再现了最近150ka黄土高原夏季风气候格局的演化过程。同时提出,这一演化过程不仅包含了控制东亚季风环流的各个成员的位置、强度及它们之间的相互配置方式等重要信息,而且可能也与极地和穿越赤道的气流有关。
By measuring the magnetic susceptibility of 30 loess-paleosol profiles covering the Loess Plateau, the second-to-last ice age (about 150 kaBP), the last inter-glacial period (about 130-74 ka BP), the last ice period (about 59-24 kaBP) A sketch of the magnetic susceptibility contour map of five characteristic climates during the last Ice Age (about 18ka BP) and the Holocene climatic suitable period (about 9ka BP). The magnetic susceptibility of loess in the extreme ice age is taken as the original susceptibility of dust to dust. The increase of magnetic susceptibility relative to this background value can be used as an indication of the summer monsoon climate in the corresponding region and its relative intensity. Based on this, the spatial pattern of the summer monsoon climate reflected by the magnetic susceptibility contour was initially recovered and the range of activities of the summer monsoon average front and the possible locations of its northern boundary were estimated, thus roughly reproducing the recent 150 ka Loess Plateau The evolution of summer monsoon climate pattern. At the same time, it is proposed that this evolutionary process not only includes important information such as the location and intensity of the members controlling the circulation of the East Asian monsoon and the way in which they are interdependent, but may also be related to the flow of polar and equatorial airways.