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Glacier growth affects the local climate, and in turn, can either promote or prohibit its own growth. Such feedback has not been considered in modeling the glaciers of the Tibetan Plateau and its surroundings (TPS) during the Last Glacial Maximum (LGM; ∼28–23 ka). We find that the volume/area of the glaciers simulated by a coupled glacier‐climate model is 20%/10% less than that by a standalone glacier model forced with fixed climate fields; glaciers advance toward their western rims and yet decrease in the interior of TPS. Such changes in spatial patterns improve model‐data comparison. Moreover, the expansion of glaciers warms the winter surface temperature of the eastern TPS and decreases precipitation almost everywhere. These effects are primarily due to the added surface elevation, which blocks the water vapor brought by westerlies and south‐westerlies, reducing precipitation and increasing surface temperatures to the east and northeast of the newly grown glaciers. Plain Language Summary: Depending on their area and volume, glaciers could impact regional atmospheric circulations, temperatures, precipitation, surface properties, etc. Changes in these climate variables would in turn feedback on the glacier growth and retreat. The glacial area over the Tibetan Plateau and its surroundings (TPS) should be much broader during the Last Glacial Maximum (LGM) than today, but glacier‐climate feedback was largely ignored in previous numerical studies. We show that the feedback significantly alters the simulated glacier area and distribution in LGM glaciers, and helps improve model‐data comparison. When glaciers grow, the surface elevation increases, which intercepts water vapor. Hence, more glaciers will grow along the western rim of TPS and less over the interior when the glacier‐climate feedback is considered. In the meantime, the winter surface temperature of the eastern Tibetan Plateau increases by more than 2 K and the precipitation over most of TPS decreases. Key Points: Coupled modeling of the Last Glacial Maximum glaciers and climate over the Tibetan Plateau and its surroundings is necessaryThe elevated glaciers blocked water vapor transport, reduced precipitation over most of TPS, and increased winter temperature in eastern TPSThe coupled glacial modeling decreases glacial area, and with changes in spatial distribution better matches the reconstructions [ABSTRACT FROM AUTHOR]

Deciphering the Meiyu behavior during the Last Interglacial (∼127 ka; LIG) may deepen our understanding of drought and flooding events over East Asia in a warmer‐than‐present world induced by Earth's orbit. Based on dynamical downscaling simulations, we suggested a 15‐ and 30‐day earlier onset and retreat of the Meiyu during the LIG relative to preindustrial, respectively, leading to a shortened Meiyu season. Meantime, extreme precipitation in the Meiyu season became stronger and occurred more frequently. Intensified monsoonal circulation, poleward‐located western North Pacific subtropical high, and poleward shift of East Asian westerly jet during the LIG provided favorable moisture conditions for earlier onset and retreat of the Meiyu. The variations of atmospheric circulations were further regulated by the joint effect of the three oceans and diabatic heating over Tibetan Plateau. Our results highlight an important role of Earth's orbit in the Meiyu and imply more flooding events in a warmer world. Plain Language Summary: The record‐breaking Meiyu in 2020 reemphasizes the importance of investigating the evolution of the rainy season in East Asia. This study reveals the response of the Meiyu to changes in the Earth's orbit during the Last Interglacial (LIG, 130–115 ka)—the warmest interglacial of the past 800 ka and a warmer world comparable to the low emission scenarios at the end of the 21st century. The Meiyu season occurred and ended earlier compared with the present day, and the duration was shortened. Additionally, more frequent and intense extreme precipitation events occurred in the Meiyu season during the LIG. The enhanced East Asian summer monsoonal flow, strengthened western North Pacific subtropical high, and poleward shift of the East Asian westerly jet in June provided favorable conditions for the earlier occurrence and termination of the Meiyu during the LIG. Moreover, changes in the sea surface temperature over the three oceans can jointly influence the Meiyu via triggering Kelvin waves, Rossby waves, and teleconnections by atmospheric circulations, with the contribution from the diabatic heating over the Tibetan Plateau. The results of this study help us better understand the evolution of the rainy season over East Asia in a warmer world. Key Points: Earlier onset and shortened duration of Meiyu season during the Last Interglacial (LIG)Stronger and more frequent extreme precipitation events occurred in Meiyu season during the LIGIntensified monsoonal circulation, poleward‐located subtropical high and westerly jets led to changes in Meiyu during the LIG [ABSTRACT FROM AUTHOR]

Investigation of the variations of hydrological cycles during the Last Interglacial (130–115 ka; LIG) may deepen our understanding of climate change in a warmer‐than‐present world induced by Earth's orbit. Here we revealed an intensified atmospheric branch of the hydrological cycle over the Tibetan Plateau (TP) in summer during the LIG relative to the preindustrial period, using the mesoscale Weather Research and Forecasting model driven by the Community Earth System Model. Our results showed that precipitation over the TP increased by 5.65 × 107 kg s−1, with 63.2% of the increase contributed by advected moisture transports, and the remaining 36.8% caused by local moisture recycling processes. As for advected moisture transports, the inflow increased by 1.93 × 107 kg s−1 and the outflow decreased by 0.87 × 107 kg s−1, respectively. Variations of the moisture transport were more profound at the eastern and northern edges, which were linked with changes in Indian summer monsoon and westerly jets. Regarding local moisture recycling processes, evaporation enhanced by 2.85 × 107 kg s−1 over the TP, influenced by variations in surface air temperature, surface net radiation flux, surface relative humidity, and surface wind fields. Increased evaporation accompanied by enhanced moisture inflow resulted in an enriched precipitation recycling ratio of ∼1% over the TP during the LIG relative to the preindustrial in summer. Our results aid in understanding the atmospheric branch of the hydrological cycle over the TP in an orbit‐induced warmer world and shed light on the future evolution of the hydrological cycle over the TP at multi‐millennial and orbital timescale. Key Points: Dynamical downscaling simulations for the Last Interglacial from Weather Research and Forecasting driven by Community Earth System ModelIntensified atmospheric branch of the summer hydrological cycle over the Tibetan Plateau during the Last Interglacial (LIG)Intensified hydrological cycle was manifested in both external and internal cycles during the LIG [ABSTRACT FROM AUTHOR]

Abstract Geological evidence shows that the Asian inland environment experienced enhanced aridity from the Early to the Late Eocene. This enhanced Eocene aridity in the Asian inland was related to combined impacts from global cooling, topographic uplift and land–sea reorganization. However, the primary cause of the enhanced Eocene aridity in this region is still under debate and varies between global cooling and early Tibetan Plateau uplift. To distinguish between the importance of these factors, we evaluate the climatic impacts of these factors from a modeling point of view. Consistent with geological evidence, our simulations support the observed enhanced Eocene aridity in the Asian inland. Both global cooling (induced by atmospheric CO 2 decrease) and topographic uplift contributed to intensified Asian inland aridity, while land–sea redistribution did not. The uplift of the central Tibetan Plateau during the early stage of the India–Asia collision is emphasized more to be responsible for the long-term Asian inland aridification during the Eocene, playing at least an equally important role as the global cooling induced by decrease in atmospheric CO 2. Highlights • Climate simulations support the observed enhanced Eocene aridity in the Asian inland. • Both the early uplift of Tibetan Plateau and the global cooling played important roles in the enhanced aridity. • The early uplift of Tibetan Plateau contributed to the long-term Asian inland aridification during the Eocene. [ABSTRACT FROM AUTHOR]