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The Intertropical Convergence Zone (ITCZ), which is the heaviest rain belt on Earth, significantly influences global hydroclimate change and livelihood of nearly 40% of the global population. However, long‐term precipitation records are sparse from the Indo‐Pacific region, especially from the southern margin of the Indo‐Pacific ITCZ, restricting our understanding of the overall natural variability of the ITCZ in the past. In this study, we present a new summer monsoonal precipitation record that spans the last 410 kyr from the southern margin of the Indo‐Pacific ITCZ, based on the logarithmic ratio between terrigenous fraction K and pelagic fraction Ca (ln(K/Ca)). Contents of both elements were derived from X‐ray fluorescence scanning on sediment cores from Site U1483 (13°05.24′S, 121°48.25′E, water depth 1,733 m) that was drilled offshore northwestern Australia during International Ocean Discovery Program Expedition 363. Comparison of the new precipitation record with published precipitation records from the northern margin and meteorological center of the Indo‐Pacific ITCZ shows that precipitation changed nearly in‐phase between the hemispheres on the precession band, possibly linked to expansion and contraction in the latitudinal extent of the Indo‐Pacific ITCZ. In contrast, interhemispheric precipitation was nearly in anti‐phase on the obliquity band, likely due to latitudinal migration of the Indo‐Pacific ITCZ. Our findings imply that tropical hydroclimate cycles were regulated by the orbital forcing but with significantly different response to changes of the ITCZ on precession and obliquity bands. Key Points: A new summer monsoonal precipitation record that spans the last 410 kyr from the southern margin of the Indo‐Pacific ITCZ was presentedInterhemispheric precipitation in‐phasing on precession band could be linked to expansion and contraction of the Indo‐Pacific ITCZInterhemispheric precipitation anti‐phasing on obliquity band could be due to latitudinal migration of the Indo‐Pacific ITCZ [ABSTRACT FROM AUTHOR]

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 CO 2 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. • Rapid intensification of Australian monsoon at end of glacial terminations I to IV • Monsoon intensification coincided with atmospheric CO 2 increase • Austral spring insolation drove southward shift of ITCZ and monsoon intensification • Formation of regional heat lows instrumental for monsoonal hydroclimate • Aeolian dust dominant during glacials and MIS 5a-d south of 20°S. [ABSTRACT FROM AUTHOR]