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This study aims to construct a novel source–receptor (SR) network to study the atmospheric water cycle associated with the East Asian summer monsoon (EASM) circulation. Using a dynamical recycling model (DRM), 68%–74% of the wet season (April–September) precipitation in six EASM land regions is attributed. The results reveal that terrestrial sources can be equally or more competitive than oceans for several sink regions downwind in East Asia. Terrestrial sources, such as the Indian subcontinent, Indochina, Southwest China, and the eastern Tibetan Plateau, are sustained by southwesterly monsoons and contribute to appreciable fractions of precipitation in the East Asian subregions downwind. Further, southwesterly and southeasterly sources for a sink region alternately dominate the moisture supply in the early and late wet season, respectively, referred to as the “SW–SE source swing.” The SR network is found to be largely governed by the zonal oscillation of the western North Pacific subtropical high and tropical cyclones. Knowledge about the coupled circulations might promise more predictability of the strength of the affected SR pairs. Notably, enhanced moisture supplies from regions such as the Indian subcontinent and Tibetan Plateau are well correlated with an upper-level wave train from western Russia. Finally, the preceding wintertime El Niño may favor (suppress) the moisture contribution of southwesterly (southeasterly) sources in the following wet season. The findings offer insights into the EASM water cycle and the governing circulations, and also accentuate the role of upwind terrestrial sources in the downwind precipitation and freshwater resources.

This study focuses on changes in the Tibetan Plateau vortices (TPVs) by using ERA5 reanalysis, covering the summers from 1979 to 2022 within the Tibetan Plateau (TP) region. These TPVs were identified using a geopotential height analysis. We discovered that the central-western TP had the most TPV activity and observed a clear decreasing trend in both the intensity and frequency of the TPVs in this region. This decrease was also accompanied by a decline in the strength of the associated vertical upward motion. To better understand this change, we employed the quasi-geostrophic omega equation. This allowed us to examine the dynamic, diabatic, and topographic factors contributing to the vertical motion during different phases of TPV activity in this region. Our results indicate that the main reason behind the weakened TPVs is the diminishing upper-level jet stream, which exerts dynamic forcing on the system. In the later stage, we observed that intensive moisture transport induces heightened diabatic vertical motion. However, this effect is not potent enough to counterbalance the diminishing dynamic influence. Therefore, our findings suggest a significant shift in TPV activity, transitioning from a dynamic-dominated regime to a latent heating-dominated diabatic regime. This new insight enhances our understanding of the complex mechanisms that influence TPV behavior.

Clustering extreme weather events are concurrent or consecutive occurrences of disastrous weather in multiple regions, resulting in cumulative impacts. Here we discovered a significant increasing trend in clustering extreme precipitation events over the Indo‐Pacific rim over the past four decades. This trend can be largely attributable to the increasing frequency of the Rossby wave response, including the circum‐Pacific and cross‐Pacific patterns due to Rossby wave activity propagation, and the Pacific anticyclone pattern due to Rossby wave breaking. The three patterns show remarkable disparity in seasonality, persistence, and hydrological impacts. They can increase the occurrences of most severe precipitation by up to 5, 8, and 25 times, respectively. The Indian Summer Monsoon heat sources and La Niña are identified as key drivers, and the mid‐latitude jet streams are modulators contributing to the events. Our findings suggest that specific Rossby wave patterns may influence the potential evolution of future clustering extremes. Plain Language Summary Extreme precipitation events that occur concurrently or consecutively in multiple regions over a period, can have a cascading effect on human livelihoods. This is a new type of disastrous weather event in the context of climate change, which we call clustering extreme precipitation events. However, there is a lack of understanding about their frequency and underlying mechanisms. To address this, we propose an identification method for clustering extreme precipitation events over the Indo‐Pacific Rim. Here, our findings reveal that three distinct Rossby wave patterns are responsible for these events. Accompanied by more frequent occurrence of the identified Rossby wave patterns, the frequency of clustering extreme precipitation events has increased (0.5 event/decade) in the past 42 years. The Rossby wave patterns set up favorable atmospheric conditions and significantly increase the occurrences of the most severe precipitation in the Northern Hemisphere. The Indian Summer Monsoon heat sources serve as a first‐order driving mechanism for exciting the Rossby waves, while La Niña serves as external forcing. Additionally, the variations of mid‐latitude jet streams modulate the development of the Rossby wave patterns. The results provide a predictability source for the sub‐seasonal to seasonal community. Key Points Over the past 42 years, there has been an increase in the frequency of clustering extreme precipitation events across the Indo‐Pacific rim The consecutive occurrences of extreme precipitation in multiple regions are organized by three diverse Rossby wave patterns The Indian Summer Monsoon heat sources and La Niña are key drivers of the events and the mid‐latitude jet streams are modulators

Atmospheric rivers (ARs) constitute a global, interconnected highway network rather than isolated regional events. In boreal summer, cross‐Pacific ARs originate over Southeast Asia, are fueled by subtropical outflows from the Asian monsoon plume, transport warm, moist air across the North Pacific, and make landfall in North America (NA). Our results show that diabatic heating anomalies over the Indian summer monsoon region and the Philippine Sea–Western North Pacific area jointly modulate AR pathways and landfalls. Numerical experiments verify that distinct heating archetypes generate diverse downstream triple‐pressure circulation structures, steering ARs toward different landfall locations. Cross‐Pacific AR activity is also modulated by climate oscillations; different phases preferentially induce distinct Indo‐Pacific heating patterns and thus redirect AR pathways. Therefore, tropical heating anomalies in Indo‐Western Pacific are valuable predictors of boreal‐summer AR activity. The interconnected “AR highways” linking Asian climate to NA and extend the predictability beyond Asia to the broader Pacific Rim.

The sudden swings between drought/heat and pluvial could cause adverse impacts far surpassing the sum of their individual effect. We propose a concept of intraseasonal “compound whiplash event” (CWE) to investigate sudden swings between wet and the compounding warm‐dry events and their changes under climate change. We find that global warming would likely escalate the compound whiplash frequency to two to three and half times (two to three times) by the end of the 21st century under the business‐as‐usual scenario (mitigated scenario). The growing threat of CWE not only stems from the increasing occurrence but also from its intensified severity and extended spatial coverage. Among all sub‐regions, East Asian summer monsoon (EASM) region would expect the largest intensification. The resulting population exposure would soar two‐to‐three‐fold over Asia. Populous regions such as North India and EASM region might face a much worse situation than the western China where population is sparse and projected to decline. Moreover, the seasonality of swings with opposite directions would further split as a response to the skewed Asian monsoon annual cycle, leading to more frequent heat‐drought to pluvial swings in spring, and more opposite‐direction swings in autumn, disrupting cultivation and water management convention. Plain Language Summary Either drought/heat or pluvial already causes adverse impacts on ecosystem and human society. The swing between these extremes could escalate their impact to the next level, far beyond their simple addition. Though some studies have investigated weather whiplash on longer time scales, such as months to years, intraseasonal whiplashes on an event basis are rarely explored. Hence, we propose a concept of “compound whiplash event” to investigate the intraseasonal alternation between warm‐dry and wet conditions and their potential changes in a warmer future climate. We find that global warming not only leads to one‐to‐two and half times more compound weather whiplashes by the end of 21st century under the business‐as‐usual scenario, but also intensifies their severity and extends their extent. Within Asia, East Asian summer monsoon region will likely face the largest increase. As a result, the population exposed to the compound weather whiplash would double or even triple, especially in the populous regions with further population growth. In addition, with skewed Asian monsoon annual cycle, the seasonality of swings expects a coherent shift, that is, more heat‐drought swings in spring and more opposite‐direction swings in autumn, potentially posing more disruption in agricultural and water management activities. Key Points Intraseasonal compound weather whiplash in Asia is introduced and defined using a 3D event‐based approach Compound weather whiplash is projected to triple with intensified severity and shifted seasonality by the end of the 21st century Southern and eastern Asia will see the most increase in population exposure while population decline tempers the increase elsewhere

The linkage between atmospheric rivers (ARs) and humid heat (HH) remains a largely unexplored research domain. This study detected 834 humid heat days (HHDs) in eastern China from 1979 to 2018, with above half of the HHDs coinciding with ARs during the boreal summer. Compared to HH not associated with ARs, those related to ARs exhibit a broader impact area and greater severity. The western North Pacific subtropical high (WNPSH)-affected and low pressure system (LPS)-affected HH types are identified to illustrate the mechanisms, and the North rainfall–South HH Dipole exists in both types. The location of WNPSH-affected HH synchronizes with the shift of WNPSH, while the LPS-affected HH is situated near the low-level LPS. Regardless of AR presence, the HH are governed by the 500 hPa geopotential height (Z500) high-pressure system, with solar radiation acting as the dominant driver of amplified surface warming. AR-related HH is further marked by a stronger 500 hPa height anomaly and reduced cloud cover, allowing more solar radiation to reach the surface, while its higher humidity is likely associated with stronger moisture transport and enhanced local evaporation. Recognizing this AR-HH co-occurrence is essential for monitoring, predicting and adapting to the most impactful HH events over eastern China.

Subseasonal precipitation whiplashes, marked by sudden shifts between dry and wet extremes, can disrupt ecosystems and human well-being. Predicting these events two to six weeks in advance is crucial for disaster management. Here, we show that the propagation diversity of the Madden-Julian Oscillation (MJO)—a key source of subseasonal predictability—will alter under anthropogenic warming. This is evidenced by a 40% increase in fast-propagating events by the late 21st century. Fast-propagating MJOs may rise in a period as early as 2028–2063, increasing the global risk of precipitation whiplashes through teleconnections. We propose a heuristic framework diagnosing that MJO’s acceleration is primarily driven by enhanced atmospheric stabilization and El Niño-like sea surface warming. The expected rise in fast-propagating MJOs could improve the predictability of subseasonal weather whiplashes, offering critical lead time for disaster preparedness. Understanding these impending shifts is essential for enhancing subseasonal prediction capabilities. This study shows that climate change will significantly increase the frequency of fast Madden-Julian Oscillation (MJO) events by 40%, resulting in more frequent sudden shifts between dry and wet extremes globally. This increase is primarily driven by enhanced atmospheric stabilization and El Niño-like sea surface warming.

Cloud radiative effect (CRE) is crucial for the development of tropical cyclones (TCs). This study investigates the impact of cloud radiation on TC seeds and TCs in an aquaplanet model by tuning ‘threshold diameter to convert cloud ice particles to snow’ (DCS). With increased cloud cover associated with higher DCS, seed frequency decreases, but the greater intensity increase of seeds leads to a higher survival rate from seeds to TCs. The changes in large-scale circulation within the models are responsible for the reduced seed frequency. Higher DCS enhances equatorial cloud liquid and ice amounts, thereby intensifying radiation heating to the tropics. Increased radiation leads to more moisture and higher temperatures at high levels and increases the temperature gradient from the tropics to the subtropics, thereby intensifying the Hadley circulation. The resulting decrease in convective available potential energy and intensification of vertical wind shear act as inhibiting factors for seed genesis. Besides, the presence of more high-level clouds accumulates both longwave and shortwave heating, creating favorable thermal conditions for the circulation to develop at the mesoscale. This process supports the growth of seeds into mature TCs, resulting in higher survival rates from seeds to TCs. The findings on TCs and CRE in aquaplanet models could serve as a foundation and provide evidence for studies conducted in more complex environmental conditions.

Tropical cyclone (TC) stalling has been widely perceived to yield a greater threat of flooding. Understanding the effect of stalling and its long‐term trends will enhance adaptation strategies to cyclone‐associated disasters. We show that stalling prolongs western North Pacific TCs to live 24 hr longer and produces 23% greater 24‐hr rainfall accumulations in a more concentrated area, which is more prominent over a 72‐hr rolling period. More importantly, we discover a northward migration of TC stalling (∼0.7°N decade−1) over 1979–2020, bringing increasingly higher flood risks to the highly‐populated East Asian coast. Further diagnoses suggest the role of binary cyclone interactions in TC stalling, whereby the second larger TC slows down the smaller one by weakening the northwestward steering flows. The northward shift of TC stalling can be explained by a similar trend in binary TC cases and environmental fields. Our findings are robust across various best track and precipitation products. Plain Language Summary Tropical cyclone (TC) stalling occurs when the cyclone resides in a small area for long. It is widely perceived to produce increased accumulated rainfall and flood risks in coastal areas nearby. However, little effort has been made to comprehensively quantify the difference in the general properties and hydrological impacts between stalled and non‐stalled TCs, as well as the spatial pattern and the possible causes of TC stalling. This study addresses the above research gaps by focusing on TC stalling over the western North Pacific (WNP) since the satellite era (1979–2020). We discover that stalling enables TCs to live significantly longer and produce greater rainfall accumulations in a more concentrated area, which is more prominent when measuring over a long rolling period (e.g., 72 hr). We highlight a northward migration of TC stalling phenomenon over the past decades, bringing increasingly greater flood risks to the highly‐populated East Asian coast, especially the Pearl River Delta. The plausible physical causes of stalling are discussed and our conclusions are validated across various sources of data. Findings here improve the understanding of TC stalling and stress the need for future adaptations against more frequent stalling events along the East Asian coasts. Key Points Stalling prolongs tropical cyclones (TCs) by 24 hr more and produces 23% greater 24‐hr rolling downpours over a more concentrated area The hydrological impacts of TC stalling are more prominent over a long rolling period (e.g., 72‐hr) A northward shift of TC stalling (∼0.7°N decade−1) brings increasingly greater threats to coastal areas in the western North Pacific

The Tibetan Plateau faces changing precipitation and environmental conditions affecting alpine ecosystems and downstream freshwater sustainability. While aerosol influence has been highlighted, how human-induced greenhouse warming impacts the plateau’s moisture recycling remains unclear. Here we show that the Tibetan Plateau’s recent precipitation changes result from enhanced precipitation recycling and moisture convergence that offset the decline in monsoon- and westerly-associated moisture transport based on 40-year Lagrangian simulations and water budget analyses. Local evapotranspiration is observed to increase faster in percentage than precipitation, a trend expected to continue in future warming scenarios according to climate projections. Greenhouse gas emission causes widespread wetting while weakening the southerly monsoons across the Himalayas, heightening the sensitivity of precipitation to evapotranspiration and thereby local land surface changes. This trend exacerbates vulnerability in the water cycle of high mountain Asia, calling for proactive management to address potential risks and ensure future water and food security in Asia.