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A large proportion (∼80%) of the Indian subcontinent's precipitation comes from the Indian summer monsoon (ISM), which influences one‐fifth of the world's population. A long‐term reliable proxy for ISM is fundamental to understanding previous global climate change. We establish a mass‐wasting‐inferred proxy to examine the paleo‐hydrogeology (river undercutting history) of the Southeast Tibetan Plateau and reconstruct the dramatic variability of ISM intensity (precipitation) in the past 130,000 years. Our data suggest that mass‐wasting events, which provides us sufficient samples for paleoclimate research, are prone to dramatic climate changes, especially extreme climate environments. The Southeast Tibetan Plateau was subjected to at least four distinct ISM intensity phases in the past 130,000 years. We conclude that ISM intensity has a cyclicity featured by the Earth's orbit with obliquity, and that ISM intensity transition lags the global ice volume (sea level) change by 8–15 kyrs. Plain Language Summary: The role of Indian summer monsoon (ISM) in the global climatic conditions has attracted considerable research attention. We reported a new long‐term proxy collected in Tibetan Plateau mass‐wasting deposits for ISM reconstruction, which is significant for coupling of tectonic evolution of Asia and global climate change in the context of global warming. This study has revealed the mutuality of paleo‐mass‐wasting events and climate changes, which confirms the relationship between surge of mass‐wasting events and global climate change (warming and increasing precipitation). ISM variability derived in our work for the last 130,000 years deduces new views of cyclicity and lag characteristics of ISM intensity. Key Points: The correlation between the occurrence of mass‐wasting deposits and the dramatic global climate changes is revealedThe variability of Indian summer monsoon (ISM) is reconstructed based on our proposed mass‐wasting‐inferred proxyNew views of cyclicity and lag characteristics of ISM intensity are deduced based on the variability of ISM intensity [ABSTRACT FROM AUTHOR]

Central Asia hosts the most extensive and highest topography on Earth, which is the result of the feedbacks among rock uplift, atmospheric circulation and moisture transport, and erosion. Here, we analyze 2,511 published low‐temperature thermochronometric ages as a proxy of the regional‐scale erosion of Central Asia. We compare these ages to tectonic and climate proxies, and state‐of‐the‐art paleoclimate simulations to constrain the influences of climate and tectonics on the topographic architecture of Central Asia. We observe a first‐order relationship between younger cooling ages in areas of high precipitation and older ages (Mesozoic) in areas that have been sheltered from precipitation, despite high strain rates. Thus, we suggest that climate enhances erosion in areas where rock uplift produces significant orographic gradients, whereas in the continental interior, areas which are tectonically active but have been sheltered from significant precipitation record older ages and a longer erosional history. Plain Language Summary: Modern topography represents the product of the relationships among climate, tectonics, and erosion through time. Central Asia is one of the most topographically diverse regions on Earth. However, the relative role of tectonics versus climate on erosion of continental Asia remains one of the major debates in Earth sciences. One way to investigate this is through the analysis of erosional proxies. In this study, we present the first regional‐scale analysis of thermochronometric ages from Central Asia as a proxy of erosion. We compare these data to tectonic processes, climate proxies, and state‐of‐the‐art paleoclimate simulations in order to constrain the relative influences of climate and tectonics on the topographic architecture and erosion of Central Asia. There is a first‐order relationship between more recent erosion and active tectonic boundaries. However, more recent erosion is also associated with areas of high precipitation, whereas areas that have been sheltered from significant precipitation retain a signal of older erosional events. Thus, we suggest that climate plays a key role in enhancing erosion in areas with developed topography and high precipitation, whereas areas which experienced sustained aridity record less erosion and preserve a record of older erosion. Key Points: Despite the magnitude of the India‐Asia collision, erosion throughout Central Asia reflects Phanerozoic tectonicsRegions of "old" erosion are preserved in more arid areas, whereas more recent erosion is concentrated in areas of high precipitationTectonic mechanisms are required to initiate erosion; however, climate modulates the magnitude of erosion [ABSTRACT FROM AUTHOR]

The relative importance of global cooling and Tibetan Plateau uplift in driving the aridification of Asia during the late Cenozoic is debated, largely due to the lack of appropriate proxy indicators. Here we address this problem by investigating changes in the source of Chinese loess and Red Clay, which is directly controlled by changes in the extent and distribution of the arid zone of Asia and the intensity of the East Asian winter monsoon, using zircon U‐Pb dating of 27 levels in a near‐continuous eolian sedimentary sequence in southern Chinese Loess Plateau. The results show that source regions expanded stepwise at ~7.2, ~2.6, 1.2–0.9 Ma, and at the Last Glacial Maximum. These changes were synchronous with global cooling and ice cover expansion in the Northern Hemisphere, suggesting that the drivers of aridification of the Asian interior were intimately related to global cooling in the late Cenozoic. Plain Language Summary: The arid and semiarid regions of Central Asia are one of the most important dust sources on Earth. Dust emitted from these regions is deposited in the Chinese Loess Plateau, the North Pacific Ocean, and even in Greenland, with broad environmental impacts. Although there is evidence that the drying of the Asian interior occurred gradually over several tens of million years, the driving factor remains unclear. Here we investigate the evolution of the sediment sources of the Chinese Loess Plateau and find that the changes in the source regions of wind‐blown sediment were synchronous with global cooling since ~7.2 Ma. This indicates that the long‐term aridification of the Asian interior was most likely driven by global cooling. Key Points: Dust source areas of the Chinese Loess Plateau expanded at ~7.2, 2.6, 1.2–0.9 Ma, and at the Last Glacial MaximumExpansion of dust source areas since ~7.2 Ma was mainly controlled by the aridification of the Asian interior and the strengthening of the East Asian Winter MonsoonAridification of the Asian interior and strengthening of the East Asian Winter Monsoon were mainly driven by global cooling [ABSTRACT FROM AUTHOR]