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Dust shortwave absorbability suffers from significant uncertainties. We investigated the radiative effects of dust aerosols from the circum‐Tibet region using four shortwave absorbability schemes and examined their impacts on the East Asian summer monsoon by using the Community Earth System Model (CESM). We adopted superspheroidal models to compute dust aerosol optical properties and found that more absorptive particles have larger asymmetry factor and lower single‐scattering albedo. Meiyu precipitation, as a part of the East Asian summer monsoon, is weakened by dust aerosols, particularly for the convective precipitation. The mechanism is that dust aerosols transported mainly from the Gobi desert radiatively heat the lower atmosphere to the north of the Meiyu rainband and decrease the meridional temperature gradient, leading to the weakening of the midtropospheric westerly jet over the Meiyu rainband, which is important for convection. More absorptive dust aerosols with a stronger radiative heating effect inhibit more convective Meiyu precipitation. Plain Language Summary: The circum‐Tibet region including the Taklimakan and Gobi deserts is the major source region of dust aerosols in East Asia particularly during the spring and summer seasons. Meiyu, as a part of the East Asian summer monsoon, generally occurs from mid‐June to mid‐July and often shows a tilt rain band extending from southwest to east China. The Letter reports on our finding about the relationship between dust shortwave absorbability (the amount of solar radiation absorbed by dust) and Meiyu precipitation. For weakly absorptive dust aerosols, convective Meiyu precipitation is rarely changed by dust aerosols; however, for strongly absorptive dust aerosols, convective Meiyu precipitation is significantly decreased. The impact of dust absorbability on Meiyu precipitation is explained through atmospheric heating rate, temperature, and wind field changes. This Letter emphasizes the urgent need of a more accurate knowledge of dust shortwave absorbability for climate modeling since significant uncertainties of refractive indices exist and new evidences show that Asian dust could be less absorptive than previously believed. Key Points: Dust shortwave absorbability affects single‐scattering albedo and asymmetry factorDust aerosols inhibit convective Meiyu precipitation depending on absorbabilityMidtropospheric westerly jet is weakened by dust aerosols causing decreased convective precipitation [ABSTRACT FROM AUTHOR]

Taiwan Island is one of the best places in the world for the study of earth surface processes during the late Quaternary because of its unique geological, geographic and climatic settings. In this study, we present sedimentary and element geochemical data of Core JRD-S drilled on the Zhuoshui River Delta, aiming to examine the changes of sediment provenance and silicate weathering intensity in response to monsoon climate variability since the last glacial period. Similar rare earth element (REE) compositions between the core sediments and modern Zhuoshui River samples suggest the Zhuoshui watershed was the dominant sediment provenance for the late Quaternary deposition in the river mouth, while the mainland rivers in southeast China including the Changjiang (Yangtze River) could not be the major sediment suppliers. Due to the stable sediment provenance, the geochemical proxy of the core sediments reveals the change of silicate weathering intensity during the late Quaternary in the Zhuoshui watershed was primarily driven by monsoon climate under an active tectonic setting. The weaker monsoonal precipitation in the last glaciation caused weaker erosion (thus less sediment supply) in the mountainous watershed and thus, increased the sediment residence time and silicate weathering intensity. In contrast, the enhanced Holocene monsoonal precipitation might greatly increase the physical erosion and sediment transfer rate from land to sea, which consequently produced more less-weathered sediments. This study provides in-depth insights into sedimentary response to tectonic and monsoon climatic changes during the Quaternary on a tectonically active high-standing island, which increases our better understanding of earth surface processes in the unique continental margin. [ABSTRACT FROM AUTHOR]