We analyse changes in terrigenous sedimentation along the northwestern Australian margin to monitor the latitudinal migration of the Intertropical Convergence Zone (ITCZ) and the shifting boundaries of climatic belts during the last four glacial cycles. We integrate high-resolution X-ray fluorescence (XRF) scanning elemental records from Core SO257–18548 and International Ocean Discovery Program Site U1482, situated southwest of the Scott Plateau at the southern edge of the present-day monsoonal belt, and from Core SO257–18571, located within the dust-cyclone belt offshore Northwest Cape south of the Exmouth Plateau. The chronology of these sediment successions is based on ¹⁴C dating over the last glacial termination and on correlation of the benthic oxygen isotope record to the LR04 stack (Lisiecki and Raymo, 200) and Antarctic ice core chronology. Our XRF derived records of riverine terrigenous run-off and aeolian dust input reveal rapid intensification of monsoonal precipitation and reduction of atmospheric dust during the Younger Dryas and early Holocene as well as during the terminal phase of other major deglaciations. Short-lived monsoonal maxima in the early Holocene (~10 ka), MIS 5e (~130 ka), MIS 7 (~200, ~220 and ~ 240 ka), and MIS 9 (~280, ~305 and ~ 330 ka) coincide with maxima in atmospheric carbon dioxide and methane concentrations. Monsoon intensification occurs during maxima in Southern Hemisphere spring (September) insolation, when intense heat low pressure cells over the Pilbara region trigger the southward shift of the ITCZ. Within the dust-cyclone belt, riverine sediment discharge was restricted to intervals of high atmospheric CO₂ concentrations, when sea surface temperature thresholds promoted cyclone formation in the tropical Indian Ocean. Northwestern Australia remained dry and arid during MIS 5a-d, when the ITCZ was locked in a more northerly position and temperature thresholds were not attained.

我们分析了沿澳大利亚西北边缘的陆源性沉积变化，以监测过去四个冰川周期中热带辐合带（ITCZ）的纬向迁移和气候带的移动边界。我们整合了高分辨率的X射线荧光（XRF）扫描来自核心SO257–18548和国际海洋发现计划站点U1482（位于当今季风带南缘斯科特高原西南方）以及来自核心SO257的元素记录–18571，位于埃克斯茅斯高原以南西北海角近海粉尘旋风带之内。这些沉积物演替的时间顺序基于¹⁴C可以追溯到最后一次冰期末期，也取决于底栖氧同位素记录与LR04堆的相关性（Lisiecki和Raymo，200）和南极冰芯年代学。我们的XRF得出的河流陆源径流和风沙输入的记录表明，季格里斯河早期和全新世早期以及其他主要冰期末期的季风降水迅速增加，大气尘埃减少。全新世早期（〜10 ka），MIS 5e（〜130 ka），MIS 7（〜200，〜220和〜240 ka）和MIS 9（〜280，〜305和〜330 ka）的短时季风最大值）与大气中二氧化碳和甲烷浓度的最大值一致。在南半球春季（9月）的日照最大值期间，季风加剧。当皮尔巴拉地区上空的高温低压单元触发ITCZ的南移时。在尘埃旋风带内，河流沉积物的排放被限制在高大气CO的间隔内当海面温度阈值促进热带印度洋的旋风形成时，浓度为₂。在MIS 5a-d期间，当ITCZ锁定在更北的位置并且未达到温度阈值时，澳大利亚西北部仍然干燥干旱。