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IntroductionThe impact of upper-ocean temperature on tropical cyclone (TC) activity is an open issue. Compared to the attention devoted to the effect of sea-surface temperature (SST) on TC activities, much less is known about the effect of ocean mixed layer depth (OMLD) on TC activities, which is determined by the ocean temperature below the surface.MethodsIn this study, a series of idealized numerical experiments were conducted to investigate the possible responses of TC activities to OMLD.ResultsIt was found that while OMLD exerts a minor influence on TC track, it evidently affects TC intensity, size, and destructiveness before reaching a certain OMLD threshold (approximately 15 m). Once the OMLD exceeds the threshold, changes in TC intensity, size, and destructiveness become marginal with further increase in OMLD. The threshold of OMLD is largely determined by TC intensity, which in turn is dictated by surface wind speed.DiscussionSpecifically, before reaching the threshold of OMLD, the surface wind, namely TC-related surface wind, may bring the cold water from below the OMLD, and effectively decreases the upper ocean temperature (including the SST). As OMLD increases, the effect of surface wind on SST cooling gradually decreases, leading to an increase of SST below the TC. Subsequently, the SST increase leads to more surface enthalpy flux (SEF) input into the TC by increasing air-sea temperature and moisture differences. By altering TC's thermodynamic and dynamic structures, the increase of SEF eventually results in the increase of TC intensity and size, and thus its destructiveness.

Daily precipitation of different intensities is expected to change differently in response to global warming. Based on station observations and simulations from the latest climate models, we investigated the non-uniform features of changes in daily precipitation frequency, intensity and amount over China. Results show that western China experiences an overall wetting trend across the spectrum of precipitation intensity, while eastern China exhibits negative trends in light-to-moderate precipitation and positive trends in heavy-to-extreme precipitation with respect to precipitation frequency and amount. Changes in precipitation intensity do not show a spatially consistent pattern of intensification in most intensity spectra, but exhibit the most pronounced intensification in heavy-to-extreme precipitation. Interestingly, changes in precipitation frequency dominate changes in the amount of precipitation for each intensity level, particularly for the spatial patterns. Although climate models show limited skills in reproducing the magnitudes of these observed changes, they show skills in simulating the sign of the changes. Also, they reasonably reproduce the observed non-uniform patterns of daily precipitation changes, especially for changes in the contributions from different intensity levels to annual total precipitation on average over the whole country. The evaluation of current climate models in simulating daily precipitation changes as a function of precipitation intensity suggests that improvement in the detection and attribution of precipitation changes in China can be gained by dividing daily precipitation into different categories.

In summer, the middle and lower reaches of the Yangtze River (MLYR) often suffers from severe floods as a result of a dominant intraseasonal oscillation (ISO) of rainfall with the quasi-period of 25–60 days. 75% of flooding events during summers of 1961–2022 are found to occur following wet phases of the 25−60-day ISO in rainfall. This study objectively extracts the optimal configuration (OC) of 25−60-day atmospheric ISOs for the wet phase of MLYR rainfall. The OC is characterized by the quadruple pattern of tropical convection configuring with the 25−60-day Silk Road Pattern (SRP) in the mid−high latitudes. The 25−60-day SRP in cooperation with tropical ISO over the western Pacific induces dipolar vertical cells over eastern China, with ascending branch between the vertical cells providing the vitally dynamical condition for MLYR rainfall. With topographic blocking of the Tibetan Plateau, the northward-propagating tropical ISO over the Indian Ocean enhances maintenance of the 25−60-day SRP via upper-tropospheric divergent flows, thus anchoring anomalous ascents to the MLYR. Numerical experiments further verify the remarkable tropical-extratropical interaction around the Tibetan Plateau in this OC. Under the global warming background, the tropical 25−60-day ISO tends to strengthen, leading to an increase in the occurrence frequency of strong OC through tropical-extratropical interaction, and thus the severe flood events doubled in summers of 1991–2020.

Abstract East Asia is undergoing significant climate changes and these changes are likely to grow in the future. It is urgent to characterize both the mechanisms controlling climate and the response of the East Asian climate system at global warming of 1.5 and 2 °C above pre-industrial levels (GW1.5 and GW2 hereafter). This study reviews recent studies on East Asian climate change at GW1.5 and GW2. The intensity and variability of the East Asian summer monsoon are expected to increase modestly, accompanied by an enhancement of water vapor transport. Other expected changes include the intensification of the Western Pacific Subtropical High and an intensified and southward shift of the East Asian jet, while the intensity of the East Asian winter monsoon is projected to reduce with high uncertainty. Meanwhile, the frequency of ENSO may increase in a warming world with great uncertainty. Significant warming and wetting occur in East Asia, with more pronounced intensity, frequency, and duration of climate extremes at GW2 than that at GW1.5. The fine structure of regional climate changes and the presence and location of various warming hotspots, however, show substantial divergence among different model simulations. Furthermore, the Asian climate responses can differ substantially between the transient and stabilized GW1.5 and GW2, which has important implications for emission policies. Thus, to better plan effective mitigation and adaptation activities, further research including an in-depth exploration of the divergent responses in transient versus stabilized scenarios, the quantification of future projection uncertainties, and improvements of the methods to reduce model uncertainties are required.

The Yangtze River Delta (YRD) is a hotspot of compound heatwaves characterized by scorching day and sweltering night persisting for more than 3 days. The YRD compound heatwaves are intimately associated with the 10–30-day variations of air temperature, with 46 identified heatwaves during the summers of 1979–2022 mostly occurring within the positive phases of 10–30-day T _max and T _min anomalies. The coincidence of positive phases in 10–30-day T _max and T _min comes from a dipole pattern of the corresponding potential vorticity (PV) anomalies in the upper troposphere. This dipole PV pattern leads to anomalous descents in the YRD and associated anticyclones in the lower troposphere. As a result, the increased adiabatic heating and incident solar radiation cause the extreme daytime heat. The enhanced humidity in the YRD increases the downward longwave radiation, resulting in the extreme nighttime temperatures. As the increased temperature and humidity enhance stratification stability in the lower troposphere, the coupling between daytime and nighttime heat extremes persists, leading to a compound heatwave. During a YRD compound heatwave, the 10–30-day atmospheric intraseasonal oscillation (ISO) exerts a potential influence on the electricity demand and supply. Continuous extreme heat leads to a dramatic surge in cooling demand. While the influence of 10–30-day ISO on wind energy resources is weak, the dipole pattern of 10–30-day PV anomalies strongly reduces solar energy resources over the mid–lower reaches of the Yellow River, thus exerting greater challenges for electricity supply to the YRD.

The rapid warming of the Tibetan Plateau (TP) in recent decades has led to severe consequences, including the melting of glaciers and snow cover, which further accelerates warming. Accurately projecting the magnitude of future warming is crucial for effective climate change adaptation. However, the projection of future temperature change is model dependent. In this study, we demonstrate a significant correlation between the historical inter-model warming trend and future temperature change, suggesting this relationship could be used to calibrate the best estimate of projections and reduce the uncertainty by observations. For a high emission scenario, the constraint helps to narrow down the uncertainty range of annual and summer temperature change on the western TP by up to 2 °C and 4 °C, respectively, in the end of this century. The most substantial calibrated increase of future change is in winter by up to 2 °C, followed by autumn with an increase by about 1 °C. Discrepancies of historical warming trend among different observation datasets expose the largest impact on the constrained best estimate compared with emergent relationship derived from different climate models and warming trend in different historical periods.

During July–September 2022, heatwaves, droughts, forest fires and floods hit the Yangtze River Valley successively, constituting a spatio-temporally compounding event. Understanding its risks matters to disaster preparedness. Through searching for event analogues in single-model initial-condition large-ensemble climate simulations, we report that the 2022 unprecedentedly widespread and intense hot drought might have occurred as early as in the 1970s, and would become increasingly possible and spatially extensive with warming. This tendency is also supported by the conventional multi-model (CMIP6) projection, especially evident in larger ensembles. Lower reaches of the valley and parts of Southwest China have greater chances of repeated exposure to the 2022-like heat—drought—fire—flood quadruple compound events. In the presence of favorable internal variability in line with future warming, it is plausible to see more than half of the valley at simultaneous risk of the 2022-like quadruple compound event. Our possibility projection highlights the urgency of accelerating the existing univariate extremes—oriented adaptation measures to better address emerging threats from unfamiliar compound hazards.

Abstract It is unequivocal that human influence has warmed the planet, which is seriously affecting the planetary health including human health. Adapting climate change should not only be a slogan, but requires a united, holistic action and a paradigm shift from crisis response to an ambitious and integrated approach immediately. Recognizing the urgent needs to tackle the risk connection between climate change and One Health, the four key messages and recommendations that with the intent to guide further research and to promote international cooperation to achieve a more climate-resilient world are provided. Graphical Abstract

Abstract Compared to singular hot or wet extremes, their occurrence in close sequence might cause larger impacts, because the initial hazard either increases exposure/vulnerability of affected communities to the next or physically worsens the second hazard. Heatwave‐preconditioned hourly precipitation extremes in the Yangtze River Valley are typical of the latter situation. Fueled by soaring convective energy after heatwaves' passage, hourly precipitation extremes are heavier, intensifying faster, and more concentrated during afternoon to evening, compared to those not proceeded by heatwaves. Consequently, flash flood‐producing events (e.g., 50 mm/hr or stronger) account for larger fractions in preconditioned events than in the non‐preconditioned group, with the spectrum difference further exaggerated by warming. This drives the frequency increase in potentially high‐impact events several‐fold larger than expected from the widely‐adopted univariate perspective. These results point to heatwave‐preconditioned hourly precipitation extremes as an emerging hazard of climate change carrying greater flash flood risks.

The Meiyu 2020 with record-breaking amount of precipitation, widespread area coverage and anomalous northern location brought about great social and economic impacts in China. However, the spatial property of anomalous rain-belt for such a catastrophic Meiyu is not well predicted. In this study, high-resolution in-situ observation and reanalysis data are used to explore key signals and possible prediction method. Results show that anomalous rain-belt of Meiyu 2020 is mainly influenced by the westward extended western North Pacific subtropical high (WNPSH) in the low-latitude and enhanced meridional circulation in mid-high latitudes. However, the distribution of composite anomalous circulation, especially in the mid-high latitude, cannot be revealed for 2020 if only considering the influence from the tropical Indo-Pacific thermal conditions. Through additional consideration of North Atlantic Oscillation (NAO), which has great contribution to circulation in the Northern Hemisphere mid-high latitudes, the anomalous key circulation features in 2020 can be appropriately captured. Also, the spatial property of anomalous rain-belt like 2020 could be accurately simulated by the established prediction model including combined effects of tropical Indo-Pacific thermal conditions and NAO. Specifically, quantified analyses prove that the warmed Indian Ocean plays a dominant role and anomalous NAO also has great importance for record-breaking area coverage and anomalous northern location of Meiyu 2020. Thus, for a more accurate prediction for anomalous rain-belt such as Meiyu 2020, the combined effects of both low- and mid-high-latitudes should be comprehensively considered.

Abstract Climate change is expected to result in more frequent and intense heat waves (HWs) in South Asia (SA). The simultaneous increases in temperature and population will exacerbate the population exposure to future HWs. Here we estimate the future population exposure to daytime and nighttime HWs in SA using the Coupled Model Intercomparison Project 6 (CMIP6) models under four Shared Socioeconomic Pathways (SSPs) during 2061–2100, relative to 1975–2014. The results show that the projected frequency and spatial extent of the daytime (nighttime) HWs will be higher under scenario SSP5‐8.5, followed by SSP2‐4.5, SSP3‐7.0, and SSP1‐2.6 (SSP5‐8.5, followed by SSP3‐7.0, SSP2‐4.5, and SSP1‐2.6), relative to the historical period. The approach presented here allows decomposing the effects of climate change and future population on the overall exposure. The results reveal that the compounding effects of projected trends in population and HWs will significantly escalate the population exposure to HWs. Under the selected SSPs, the total population exposure to daytime and nighttime HWs ranges from 185 to 492 and 204–555 million people‐event, respectively, with the maximum exposure occurring in the Indo‐Gigantic Plain. The wide range of exposed populations highlights the sensitivity of the overall exposure to our future socioeconomic pathway decisions, emphasizing the importance of curbing anthropogenic greenhouse gas emissions and adopting sustainable urban planning solutions to minimize the potential socioeconomic and health impacts of HWs.

Tropical cyclones (TCs) seriously threaten the safety of human life and property especially when approaching a coast or making landfall. Robust, long-lead predictions are valuable for managing policy responses. However, despite decades of efforts, seasonal prediction of TCs remains a challenge. Here, we introduce a deep-learning prediction model to make skillful seasonal prediction of TC track density in the Western North Pacific (WNP) during the typhoon season, with a lead time of up to four months. To overcome the limited availability of observational data, we use TC tracks from CMIP5 and CMIP6 climate models as the training data, followed by a transfer-learning method to train a fully convolutional neural network named SeaUnet. Through the deep-learning process (i.e., heat map analysis), SeaUnet identifies physically based precursors. We show that SeaUnet has a good performance for typhoon distribution, outperforming state-of-the-art dynamic systems. The success of SeaUnet indicates its potential for operational use.

Compound hot extremes that combine day- and nighttime heat have particularly strong impacts. Here, the authors show that anthropogenic emissions of greenhouse gases have made compound hot extremes increasingly frequent and intense, and project that under future emissions four to eight times as many people will be affected by them by 2100.

Climate change is not only about changes in means of climatic variables such as temperature, precipitation and wind, but also their extreme values which are of critical importance to human society and ecosystems. To inspire the Swedish climate research community and to promote assessments of international research on past and future changes in extreme weather events against the global climate change background, the Earth Science Class of the Royal Swedish Academy of Sciences organized a workshop entitled ‘Extreme weather events in a warming world’ in 2019. This article summarizes and synthesizes the key points from the presentations and discussions of the workshop on changes in floods, droughts, heat waves, as well as on tropical cyclones and extratropical storms. In addition to reviewing past achievements in these research fields and identifying research gaps with a focus on Sweden, future challenges and opportunities for the Swedish climate research community are highlighted.

Abstract The dust generated in East Asia influences the western North America (WNA) through its trans‐Pacific transport. This study investigates the distinct contribution between two main dust sources in East Asia on this remote influence based on Modern‐Era Retrospective analysis for Research and Applications version 2 data set. Results show that the dust generated in Gobi desert (GD) exerts a larger influence on the WNA compared to those in Taklimakan desert (TD). This difference is attributed to the different terrain and background winds in GD and TD. The GD is relatively flat and dominated by westerlies throughout the troposphere, which facilitates the trans‐Pacific transport of dust to WNA. However, the TD is located in the Tarim Basin and dominated by easterly wind in the lower troposphere. The uplifted dust is largely redeposited in TD. Moreover, the influence of GD on dust in WNA experiences decadal change around 1999, which is related to intrinsic change of dust loading in GD.

Abstract The Paris Agreement has motivated rapid analysis differentiating changes in frequency/intensity of weather and climate extremes in 1.5 versus 2 °C warmer worlds. However, implications of these global warming levels on locations, spatial scales, and emergence timings of hot spots to extremes are more relevant to policy‐making but remain strikingly under‐addressed. Based on a bivariate definitional framework, we show that compared to 2 °C, the 1.5 °C target could avoid a transition of prevailing type of summertime hot extremes from daytime‐/nighttime‐only events to combined daytime‐nighttime hot extremes in approximately 18% of global continents and protect 14–26% of land areas from seeing over threefold‐to‐tenfold increases in occurrence of combined hot extremes. This half‐a‐degree reduction also matters for around 21% of global lands, mostly within the tropics, in constraining historically unprecedented combined hot extremes from becoming the new norm within just one to three decades ahead. By contrast, previous analyses based on univariate‐defined hot days substantially underestimate the magnitude, areal extent, and emergence rate of 0.5 °C‐caused aggravation of summertime hot extremes. These projected changes of bivariate‐classified hot extremes, therefore, underline not only the imperative but also the urgency of striving for the lower Paris target.

Abstract Aerosol effects on convective clouds and associated precipitation constitute an important open-ended question in climate research. Previous studies have linked an increase in aerosol concentration to a delay in the onset of rain, invigorated clouds and stronger rain rates. Here, using observational data, we show that the aerosol effect on convective clouds shifts from invigoration to suppression with increasing aerosol optical depth. We explain this shift in trend (using a cloud model) as the result of a competition between two types of microphysical processes: cloud-core-based invigorating processes vs. peripheral suppressive processes. We show that the aerosol optical depth value that marks the shift between invigoration and suppression depends on the environmental thermodynamic conditions. These findings can aid in better parameterizing aerosol effects in climate models for the prediction of climate trends.

Compound extreme events always cause severe impacts on human society and the natural system, especially in the populated areas. However, studies on their changes depend on definitions of the related extreme events. In this study, a newly defined compound drought and hot extreme events (CDHEEs) index based on the day-night concurrent hot extreme index and daily drought monitoring index is defined to explore possible changing features in summer-time CDHEEs from 1961 to 2018 in the densely populated areas of eastern China. Results reveal that the occurrence of CDHEEs shows a significant increase in the densely populated areas with the strengthening interaction of drought and hot extreme events, especially since the late 1990s. Further analyses indicate that urbanization and regional climate also moderate changes in CDHEEs, as we found that CDHEEs increased more prominently in the cities, especially in the drier regions. As a result, the population exposed to CDHEEs has doubled since the late 1990s in the densely populated areas of eastern China.

Tropical cyclones (TCs) and heatwaves are amongst the most deadly and costly natural hazards. Despite considerable advances in understanding each of them, their occurrences in rapid sequence (e.g. in a week) that introduce disproportionately large impacts to infrastructure and human health have received far less attention. Based on dynamical downscaling simulations, we project that currently rare landfalling TC-heatwave compound events would be five to ten times more frequent in coastal Southeast China, and migrate northward and westward to the intact interior. It is the substantial increase in heatwaves that contributes most to the projected increase in frequency and novel emergence of compound events. There would be higher fraction of severer compound events composed of either intense TCs (in the top 10% historically) or exceptional heatwaves (above the historical 99.9th percentile), with coastal Southeast China even bracing for out-of-ordinary combinations of the two. On top of the unprecedented frequency, intensity and land exposure, future emergence of unseasonal compound events in South and Southeast China would further overwhelm local adaptive capacities.

Warming has resulted in increases in frequency, intensity and/or duration of droughts in most land regions over the globe. Nevertheless, knowledge on how ecosystem water use efficiency (WUE) responds to extreme drought stress and whether the responses are affected by drought timing is still limited. In this study, we examined the changes in ecosystem WUE under extreme drought years over Northern Eurasia during 1982–2011 and further assessed WUE responses to droughts with separate groupings designed to characterize the timing of extreme drought stress. We found that drought timing indeed influenced the responses of ecosystem WUE under extreme drought years. Negative impacts of extreme drought stress during the dry season on ecosystem WUE were more remarkable than those from extreme drought stress during the wet season. Particularly, impacts of droughts on ecosystem carbon–water interactions differed among ecosystem types due to the specific hydrothermal condition of each biome. The information provided by our analyses plays an importance role in identifying water use strategies of terrestrial vegetation in response to drought stress and will help improve our understanding and predictions of the response of ecosystem WUE to global environmental change.

Wetting in the south while drying in the north during the last few decades constitutes the well-known ‘southern flood–northern drought’ (SFND) precipitation pattern over eastern China. The fingerprint of anthropogenic influence on this dipole pattern of regional precipitation trends has not been confirmed, especially for forced changes in relevant dynamics at the synoptic scale. Using a process-based approach involving model experiments both with and without anthropogenic inputs, it is demonstrated that the occurrences of daily circulation patterns (CPs) governing precipitation over eastern China during 1961–2013 have been altered by human influence. Due to anthropogenic forcing, CPs favoring SFND have become more likely to occur at the expense of CPs unfavorable to SFND. Regression analysis shows that changes recorded in the occurrence of CPs from the factual simulations could explain a large part of the precipitation trends over eastern China. CP frequencies driven by purely natural forcing do not reproduce this dipole pattern nor the inferred magnitude of precipitation trends over eastern China. These results suggest that human influence has played a critical role in shaping the contrasting north–south precipitation trends.

Using data collected from a specially designed experiment at the Dunhuang Station (40°10′N, 94°31′E, 1150 m) from September 2017 to September 2018, we have characterized the influences of soil moisture and solar altitude on surface spectral albedo in an arid area. The specific settings of our experiment allowed us to minimize the influences of underlying surface, cloud cover, aerosol and weather conditions, and thus highlight the influence of soil moisture and solar altitude. During the timespan of the experiment, we observed the annual mean surface albedo of global radiation (GR), ultraviolet radiation (UV), visible radiation (VIS) and near-infrared radiation (NIR) to be 0.24, 0.11, 0.24 and 0.25. A significantly negative linear correlation between surface albedo and soil moisture was identified, with the correlation coefficients between GR, UV, VIS, NIR and soil moisture being −0.68, −0.75, −0.70 and −0.61. In addition, we identified an exponential relationship between surface albedo and solar altitude. The exponential regression coefficients are −0.21, −0.077, −0.53 and −0.21, respectively. From these analyses, we derived a new two-factor parametric formula for depicting the influence of soil moisture and solar altitude on surface spectral albedo. Using observation data, we demonstrate that the formula recapitulates the real-world relationship between soil moisture, solar altitude and surface spectral albedo with little deviation. These findings may help us gain a deeper understanding of improving land surface parameterizations and have potential implications for solar energy research and applications.

Despite intense discussions on the recent boom of mid-latitude wintertime cold extremes, co-variations of warm and cold extremes, i.e. winter temperature volatility, has garnered substantially less attention. Apart from using temperature extremes’ frequency and intensity, we also define ‘temperature whiplash’, which depicts rapid switches between warm and cold extremes, to measure winter temperature volatility in China. Results show that Northeast-, Northwest-, Southwest-, Southeast-China and the Yangtze River Valley have experienced increasingly volatile winters after 1980, co-occurring with precipitous decline in Arctic sea-ice. This enhanced volatility has a strong expression in significant increases in temperature whiplash events, with some hotspots also seeing both warm and cold extremes become more frequent and/or intense. An observation-based detection analysis highlights the dominance of intrinsic atmospheric variability over both anthropogenic warming and sea-ice decline during 1980–2018 in driving winters in China to be more volatile over this period.

Projected changes of the thermal growing season (TGS) over Northern Eurasia at 1.5 °C and 2 °C global warming levels are investigated using 22 CMIP5 models under both RCP4.5 and RCP8.5 scenarios. The multi-model mean projections indicate Northern Eurasia will experience extended and intensified TGSs in a warmer world. The prolongation of TGSs under 1.5 °C and 2 °C warming is attributed to both earlier onset and later termination, with the latter factor playing a dominating role. Interestingly, earlier onset is of greater importance under RCP4.5 than under RCP8.5 in prolonging TGS as the world warms by an additional 0.5 °C. Under both RCPs, growing degree day sum (GDD) above 5 °C is anticipated to increase by 0 °C–450 °C days and 0 °C–650 °C days over Northern Eurasia at 1.5 °C and 2 °C warming, respectively. However, effective GDD (EGDD) which accumulates optimum temperature for the growth of wheat, exhibits a decline in the south of Central Asia under warmer climates. Therefore, for wheat production over Northern Eurasia, adverse effects incurred by scorching temperatures and resultant inadequacy in water availability may counteract benefits from lengthening and warming TGS. In response to a future 1.5 °C and 2 °C warmer world, proper management and scientifically-tailored adaptation are imperative to optimize local-regional agricultural production.

The western Sichuan Basin (WSB) is a rainstorm center influenced by complicated factors such as topography and circulation. Based on multivariable empirical orthogonal function technique for extreme precipitation processes (EPP) in WSB in 2013, this study reveals the dominant circulation patterns. Results indicate that the leading modes are characterized by “Saddle” and “Sandwich” structures, respectively. In one mode, a TC from the South China Sea (SCS) converts into the inverted trough and steers warm moist airflow northward into the WSB. At the same time, WPSH extends westward over the Yangtze River and conveys a southeasterly warm humid flow. In the other case, WPSH is pushed westward by TC in the Western Pacific and then merges with an anomalous anticyclone over SCS. The anomalous anticyclone and WPSH form a conjunction belt and convey the warm moist southwesterly airflow to meet with the cold flow over the WSB. The configurations of WPSH and TC in the tropic and the blocking and trough in the midhigh latitudes play important roles during the EPPs over the WSB. The persistence of EPPs depends on the long-lived large-scale circulation configuration steady over the suitable positions.

During the past two decades since 1997, eastern China has experienced a warming hiatus punctuated by significant cooling in daily-minimum temperature (Tmin), particularly during early–mid winter. By arbitrarily configuring start and end years, a ‘vantage hiatus period’ in eastern China is detected over 1998–2013, during when the domain-averaged Tmin exhibited the strongest cooling trend and the number of significant cooling stations peaked. Regions most susceptible to the warming hiatus are located in North China, the Yangtze–Huai River Valley and South China, where significant cooling in Tmin persisted through 2016. This sustained hiatus gave rise to increasingly frequent and severe cold extremes there. Concerning its prolonged persistency and great cooling rate, the recent warming hiatus over eastern China deviates much from most historical short-term trends during the past five decades, and thus could be viewed as an outlier against the prevalent warming context.