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In mid-June to July 2023, North China witnessed extreme heatwaves, marked by intense near-surface warming with an advanced seasonal cycle of local air temperature. An unconventional upper-tropospheric cold vortex in early June, deviating from conventional "heat dome" patterns, preceded the heatwave extremes. The zonal SSTA gradient in Indo-Pacific warm pool initially suppressed Indian summer monsoon convection, which stimulated the cold vortex around North China via a tropical-extratropical teleconnection. This anomaly intensified the air-land thermal contrast, leading to increased sensible heating and reduced soil moisture in situ. The drier soil conditions maintained and further augmented sensible heating, escalating surface air temperature, and culminating in extraordinary heatwaves. The air column was then destabilized to mitigate the upper-level cold vortex. Historical records corroborate the extremity of the air-sea interactions in 2023. The ECMWF real-time subseasonal-to-seasonal (S2S) forecasts successfully capture the air-land feedback in both cold vortex and heatwave stages, albeit with an underestimation of heatwave intensity due to biases in soil moisture anomalies. Consequently, the initial cold vortex condition and air-land-sea interactions yield S2S predictability to the historic 2023 heatwaves in North China. [ABSTRACT FROM AUTHOR]

In 2022, South China suffered severe flooding due to unexpected persistent heavy rainfall in the pre-flood season. The in situ cumulative precipitation amount during May–June in South China broke the record established in 1981. The present study ascribed this record-breaking event to extreme warm sea surface temperature anomalies (SSTAs) in the Northeast Pacific (NP) and the Maritime Continent (MC) region. In May, the NP warming associated with La Niña and the negative phase of the Pacific Decadal Oscillation intensified extratropical diabatic heating and induced a cyclonic anomaly over Northeast Asia, which shifted the East Asian trough (EAT) southward. Subsequently, the westerly wind accelerated to the south of the anomalous EAT and strengthened the western North Pacific subtropical high, which led to increase in rainfall over South China. In June, the rainfall over South China remained above normal owing to anomalies of the meridional monsoon circulation manifested as a response to the development of a warm SSTA in the MC region. The anomalous warming in the deep tropics suppressed the Asian summer monsoon convection through anomalous atmospheric descent over South Asia, accompanied by enhanced atmospheric ascent and increased water vapor convergence over South China. Numerical sensitivity experiments validated the above processes and indicated that historic warm SSTAs in the NP and MC regions could increase the probability of extreme persistent above-normal pre-flood rainfall over South China. The results support improved predictability of pre-flood rainfall over South China on the interannual timescale outside the equatorial central–eastern Pacific. [ABSTRACT FROM AUTHOR]

A record‐breaking flooding event occurred in Zhengzhou, Henan Province of China during 17–23 July 2021, causing hundreds of deaths and vast economic losses. Here, we evaluated the predictability of this extreme rainfall event and the impacts of tropical cyclones (TCs) using subseasonal‐to‐seasonal (S2S) operational models. On the monthly timescale, most models initialized in late June reasonably predicted the wet‐in‐north and dry‐in‐south patterns of anomalous rainfall over China in July, accompanied by the well‐predicted westward extension of the western North Pacific subtropical high (WNPSH) and eastward stretching of the South Asian High. On the weekly timescale, only four models captured the location, probability, and sudden intensification of the rainfall extremes in advance of 1 week, largely due to their reasonable prediction of WNPSH variability in mid‐latitudes. However, the S2S models still underestimated the super extremeness of this event. The prediction discrepancies came from the poor predictability of Typhoon IN‐FA and its impact on the daily evolution of the extreme rainfall event, even within a few days forecast lead. Compared with the observation, the prediction bias of tropical disturbance changed the environmental monsoon airflow to induce the earlier warning of rainfall extremes prior to the formation of IN‐FA. After the formation of IN‐FA, the prediction bias of the typhoon's moving speed distorted the typhoon location, which incorrectly predicted the moisture convergence center and underestimated their remote impacts on this heavy rainfall event. Plain Language Summary: Unprecedented heavy rainfall reaches the warming Earth more frequently, creating the need for effective risk‐warning alerts that utilize subseasonal‐to‐seasonal (S2S) forecasting to integrate information from nowcasting, weather, and seasonal predictions. On 17–23 July 2021, persistent heavy rainfall affected Henan Province of China, triggering devastating flooding and traffic chaos in Zhengzhou city. Some skillful S2S models can reasonably predict the monthly rainfall pattern in July. Although the chance of exceeding the new record daily rainfall is only approx. 0.7% in mid‐late July, they provide a high probability of this heavy weekly rainfall 1 week in advance. Nevertheless, the S2S models underestimate this super extremeness, mainly due to the poor predictability of tropical cyclones, even within a few leading days. The deficits in the tropical disturbance and moving speed of Typhoon IN‐FA in the model forecast altered the moisture transmission, underestimating their remote impacts on this extreme event. Risk management on S2S timescales is essential for many public and private sectors, as it provides pivotal lead times that save lives and property. Each extreme event exposes challenges regarding the credibility and sensitivity of the outcomes for decision‐making. Future research should improve our awareness of the challenges that remain in the S2S forecasts. Key Points: Most subseasonal‐to‐seasonal models produce the wet‐in‐north and dry‐in‐south rainfall anomalies and general circulation configuration over China in JulySudden intensification of rainfall in Henan China was predicted 1 week ahead by four models with accurate mid‐latitude adjustmentsDeficits in tropical disturbance and moving speed of Typhoon IN‐FA underestimate their remote impacts in forecasting [ABSTRACT FROM AUTHOR]

The rainy season typically terminates over the area of central northern China (CNC) in late August with the rapid retreat of the East Asian summer monsoon (EASM). However, the CNC suffered continuous heavy rainfall in September 2021. The monthly accumulative precipitation amount broke its historical record since 1961 and caused severe floods. The present study ascribes this extreme rainfall event to the westward inland intrusion of the western North Pacific subtropical high (WNPSH). Both case study and statistical analysis indicate that westward extension of the WNPSH is significantly positively correlated with convection over the Maritime Continent (MC) and northern Indian Peninsula (NIP) under the influence of sea surface temperature anomalies (SSTAs). Atmospheric general circulation model (AGCM) experiments validate the individual and combined effects of SSTAs in the tropical Indo-Pacific–Atlantic Oceans on WNPSH and CNC rainfall. In particular, the warm SSTAs in the Indo-Pacific warm pool increase the probability of extremely westward extension of the WNPSH and above-normal rainfall over the CNC. The cold SSTAs in the equatorial central-eastern Pacific enlarge the zonal SSTA gradient, strengthen the anomalous convection over the MC and NIP, and intensify the WNPSH and CNC rainfall anomalies. Meanwhile, the warmer tropical Atlantic anchors the anomalous WNPSH and CNC rainfall in their observed positions. A statistical model based on the tropical SSTAs in August can skillfully predict the westward extension of the WNPSH in September 2021, suggesting that the combined effects of tropical Indo-Pacific–Atlantic SSTAs in late summer possibly tend to prolong rainy season of the EASM until early autumn. [ABSTRACT FROM AUTHOR]

Enhanced predictability of high-impact weather events is a Subseasonal to Seasonal Prediction Project (S2S) priority. In early summer 2020, a record-breaking heavy rainfall event occurred over the Yangtze River valley during the mei-yu season (June and July). Here we evaluate the S2S model forecast performance concerning the summer 2020 extreme mei-yu event over the Yangtze River valley. Our results show all operational S2S models exhibit fluctuating high-low–high forecast skill patterns during this three-stage mei-yu event, determined by different dominant circulations. In particular, the poor mid-latitude circulation forecast (low trough over northern China) in the North Atlantic Oscillation (NAO) negative phase, with relative more contribution than that of the low-latitude circulation (western North Pacific subtropical high and South Asian high), decreases the model forecast skill for mei-yu rainfall in early-mid July. The prediction barrier of the NAO pattern and its downstream response, via the eastward-propagating wave train, jointly decrease the rainfall forecast skill during the NAO active negative period. Therefore, the skillful model prediction of the active summer NAO could help predict mei-yu events in the East Asian summer monsoon, suggesting further model improvements to the S2S forecasting of summertime mid-latitude variations are urgently needed. [ABSTRACT FROM AUTHOR]

Background: The prevalence of anxiety and depression symptoms among caretakers of children with atopic dermatitis (AD) and associated factors is unclear. The study was designed to explore anxiety and depression symptoms among caretakers of AD, and screen factors associated with anxiety and depression symptoms. Methods: A total of 901 children with AD and their caretakers were continuously enrolled and interviewed at dermatology department of Capital Institute of Pediatrics, Beijing, China. Children's medication was administered by their caretakers. Caretakers' anxiety and depression symptoms were evaluated by Hamilton Depression Rating Scale-17 and Hamilton Depression Rating Scale, while medication compliance was evaluated and divided into poor (< 6 points), moderate (6–7 points), and good (> 7 points) by Morisky Medication Adherence Scale. Multilevel ordered logistic regression was used to screen factors associated with caretakers' anxiety and depression. Results: Among caretakers, 41.5% had anxiety symptoms, 39.6% had depression symptoms, 51.4% have any of the two and 29.7% had both of the two. Factors associated with caretakers' anxiety symptoms included longer duration of the illness (OR, 0.99, 95% CI 0.98–0.99) and taking care of children with severe AD (OR, 2.55, 95% CI 1.43–4.55). Factors associated with caretakers' depression symptoms included higher educational level (OR, 0.56, 95% CI 0.39–0.80), taking care of children with moderate (OR, 2.01, 95% CI 1.15–3.50) and severe AD (OR, 3.99, 95% CI 2.10–7.59) and poor medication compliance (OR, 3.45, 95% CI 1.13–10.56). Conclusions: Prevalence of anxiety and depression symptoms among caretakers of AD were high. Attention should be paid to caretakers of AD at higher risk for those psychological problems. [ABSTRACT FROM AUTHOR]

Accurate forecasting of the South China Sea summer monsoon (SCSSM) onset is critical for water resource management in the rainy season across East Asia. The present work evaluates the skill of the ECMWF subseasonal‐to‐seasonal (S2S) forecasting system in predicting SCSSM onset dates using a hindcast experiment. The model provides accurate predictions of the SCSSM onset date 10 days in advance. The predictability mainly arises from the sea surface temperature anomaly (SSTA) in the northern Indian Ocean and central‐eastern tropical Pacific, which usually coincides with moderate and extreme decaying El Niño, thus creating windows of opportunity for SCSSM onset forecasting. The model can reasonably reproduce the SCSSM‐related SSTA and its induced atmospheric teleconnections. However, when anomalous Ural blocking influences the mid‐high latitudes, the ECMWF model forecasts of the SCSSM onset are trapped in the synoptic timescale because of the limited ability of the model to consider blocking in forecasting. Plain Language Summary: Accurate predictions of when the monsoon arrives greatly influence agricultural planning. Agro‐based China relies on East Asian summer monsoon rainfall, which allows millions of farmers to feed the most populated country in the world. The summer monsoon over the South China Sea marks the start of the monsoonal rainy season in East Asia. Therefore, forecasting its arrival with a long lead time is essential. A subseasonal forecasting system is an effective tool for monsoon prediction, but little attention has been given to the South China Sea. We use the European Center for Medium‐Range Weather Forecasts system to evaluate subseasonal forecasts of the monsoon onset over the South China Sea. Skillful forecasts can be obtained 10 days in advance. The predictability originates from the accurate representation of the tropical sea surface temperature and its impact on the atmosphere, particularly concomitant with the moderate and extreme decaying El Niño. However, a synoptic system, called Ural blocking, constrains the forecast skill because it is difficult to model. Both the predictive sources and limitations are discussed in our results, which can be used to improve monsoon arrival forecasts. These improvements will benefit the proactive adaptation since policy changes may take several weeks to implement. Key Points: The European Center for Medium‐Range Weather Forecasts S2S model provides accurate 10‐day advance forecasts of the onset date of the South China Sea summer monsoon (SCSSM)The high S2S predictability of the SCSSM onset mainly arises from the forcing of slowly evolving tropical sea surface temperaturesUnpredictable Ural blocking at mid‐high latitudes may hinder forecasts of the SCSSM onset due to synoptic disturbance [ABSTRACT FROM AUTHOR]

Using daily atmospheric circulation data for 1981–2010, we identify the climatological intraseasonal oscillation (CISO) in the mid–upper troposphere and reveal its critical role in anchoring the Meiyu season to the period from mid‐June to mid‐July and the rainfall episode of northeastern China to begin in late July. Wavelet analysis shows a significant 20–90‐day period in the climatological 200‐ and 500‐hPa zonal winds during boreal summer, indicating the existence of the zonal wind CISO in the mid–upper troposphere. The leading mode of zonal wind CISO features a dipole pattern along the coast of East Asia controlled by convection over the southeastern China–western North Pacific (SC–WNP). In mid‐June, suppressed convection over the SC–WNP induces the negative phase of intraseasonal Pacific–Japan pattern, leading to the strong anticyclone with a poleward tilt with height to dominate over the WNP. Consequently, more moisture are transported to the middle and lower reaches of the Yangtze River Valley (YRV), and the mid‐tropospheric (upper‐tropospheric) East Asian westerly jet (EAWJ) is shifted north of 32°N (36°N), which further increases the YRV rainfall through enhancing warm advection and upper‐tropospheric divergence, thus facilitating the initiation of Meiyu season. In mid‐July, active convection occupies the SC–WNP instead, with the reversed circulation pattern terminating the Meiyu season. In late July, active convection shifts from the equator to the tropical western Pacific, leading to the second mode of zonal wind CISO, which is characterized by a quasi‐barotropic Mongolian anticyclone in the mid–upper troposphere. The upper‐tropospheric EAWJ is further shifted to 45°N, displacing the induced upper‐tropospheric divergence northward, thus initiating the rainfall episode of northeastern China. [ABSTRACT FROM AUTHOR]

The onset of the South China Sea summer monsoon (SCSSM) has traditionally been ascribed to El Niño–Southern Oscillation (ENSO) on an interannual time scale, but the two do not correspond in some years. The present study applies harmonic analysis on the meridional temperature gradient (MTG) in the mid–upper troposphere over the South China Sea (SCS) and decomposes the onset process to be a slow-varying seasonal cycle and transient subseasonal component. The ENSO-related air temperature anomaly in the southern SCS provides seasonal predictability of SCSSM onset by a stable and robust relationship between ENSO and MTG seasonal cycle. However, in the northern SCS, the MTG is regulated by an intraseasonal oscillation (ISO) of extratropical air temperature with a significant 10–30-day period. This ISO originates over the western Tibetan Plateau (TP) and then propagates eastward and gets enhanced by anomalous diabatic heating due to spring rainfall anomaly over South China as a result of subseasonal thermal forcing of TP. When the ISO arrives to the north of the SCS, it directly changes the tropospheric temperature to modulate the MTG. Meanwhile, the upper-level circulation associated with the ISO alters the meridional potential vorticity advection and pumping effect, followed by the anomalous low-level westerly wind and monsoon convection over the SCS. The SCSSM onset is evidently disrupted from its seasonal cycle when this ISO is more active. Since the independence of its intensity from ENSO, this extratropical ISO over TP and South China provides additional subseasonal predictability of the onset dates of the SCSSM. [ABSTRACT FROM AUTHOR]

The middle and lower reaches of the Yangtze River (MLRYR) exhibit notable interannual variability in seasonal-mean air temperature amid ongoing global warming. This study elucidates the specific mechanisms governing anomalous air temperatures during early (June) and late summer (July to August) in the MLRYR. Early summer temperatures arise from anomalous sinking driven by negative anomalies in moist enthalpy advection in the lower troposphere, as a response to warm sea surface temperature anomalies (SSTA) in the tropical western Pacific. This induces a low-level cyclone anomaly over Southeast Asia, reducing specific humidity and determining anomalous vertical motion over the MLRYR. In contrast, late summer temperatures are induced by mid-upper tropospheric descending anomalies over the MLRYR. The combined influence of SSTA in the western Pacific and North Atlantic sustains warmer air by reinforcing a barotropic anticyclone over North China through a mid-latitude wave train. Subsequent anomalous negative potential vorticity advection in the upper troposphere strengthens sinking motion over the MLRYR. The seasonal evolution of the East Asian summer monsoon and SSTA is pivotal in the distinct mechanisms governing warmer air temperatures over the MLRYR. While numerical experiments capture general features, the regulation of SSTA is subject to uncertainty due to the atmospheric intrinsic patterns. This research distinguishes predictability sources of air temperature anomalies over the MLRYR between early and late summer, emphasizing the combined influence of SSTA beyond the ENSO domain on East Asian climate. • Hotter summers in the MLRYR primarily come from the persistent higher temperature in situ. • The mechanisms for the MLRYR higher temperature are distinct between early and late summer. • SSTA outside the ENSO domain determines monthly evolution of summer air temperature anomalies over the MLRYR. [ABSTRACT FROM AUTHOR]

A seasonal evolution of rainbands over East China is evident and shows remarkable year-to-year variations. The present study identifies two dominant interannual modes of the seasonal evolution of rainbands over East China from 1981 to 2018: 1) the sudden change pattern, in which the anomalous rainfall changes abruptly from boreal spring to summer, especially over South China; and 2) the northward migration pattern, which shows a gradual poleward migration of the anomalous rainband over East China with the East Asian summer monsoon (EASM). Both of them are regulated by the sea surface temperature anomalies (SSTAs) in the Northern Hemisphere from spring to summer. In the sudden change pattern, the SSTAs in the Pacific modulate spring rainfall over South China via the ENSO–EASM teleconnection. By contrast, the North Atlantic SSTAs change the midlatitude wave train and modify summer rainfall over South and North China, in conjunction with the anomalous tropical circulation due to the Indian Ocean SSTAs. In the northward migration pattern, the North Pacific SSTAs alter spring rainfall over South China by varying the low-level western North Pacific subtropical high and the zonal land–sea thermal contrast over East Asia. Afterward, the ENSO-like SSTAs induce a Pacific–Japan teleconnection and shift the anomalous rainband northward to the Yangtze–Huai River and North China in summer. The seasonal switch of the SSTAs regulating these two modes is physically linked from boreal spring to summer. This mechanism provides potential seasonal predictability of the seasonal evolution of the anomalous rainband over East China. [ABSTRACT FROM AUTHOR]

Two types of three-dimensional circulation of the East Asian summer monsoon (EASM) act as the coupling wheels determining the seasonal rainfall anomalies in China during 1979–2015. The first coupling mode features the interaction between the Mongolian cyclone over North Asia and the South Asian high (SAH) anomalies over the Tibetan Plateau at 200 hPa. The second mode presents the coupling between the anomalous low-level western Pacific anticyclone and upper-level SAH via the meridional flow over Southeast Asia. These two modes are responsible for the summer rainfall anomalies over China in 24 and 7 out of 37 years, respectively. However, the dominant SST anomalies in the tropical Pacific, the Indian Ocean, and the North Atlantic Ocean fail to account for the first coupling wheel's interannual variability, illustrating the challenges in forecasting summer rainfall over China. [ABSTRACT FROM AUTHOR]

Meiyu rainfall in June–July of 2020 hit the Yangtze‐Huaihe River basin, and the precipitation at lots of observational stations broke the records, inducing severe disasters there. Tibetan Plateau vortices (TPVs) generated over the Tibetan Plateau are local major rainfall triggers. In previous knowledge, TPVs can affect the rainfall in eastern China, only after emigrating from the Tibetan Plateau. In this work, roles of TPVs in the record Meiyu are revealed, implying that the effects of TPVs may be underestimated previously. Firstly, TPVs dying out over the Tibetan Plateau may be transformed into troughs and continue to move eastward, influencing the rainfall in Yangtze‐Huaihe River basin. Secondly, southwest vortices, the important rainfall producers in China, tend to be generated and maintained when TPVs are located over eastern plateau. The results give extended knowledge on the effects of TPVs, which are beneficial for the rainfall prediction in eastern China. [ABSTRACT FROM AUTHOR]

In 2020, the Yangtze River (YR) suffered a long‐persisting Meiyu season. The accumulated rainfall broke its record since 1961 and caused severe flooding and death in China. Our results show the sequential warm and cold Meiyu front regulated by the North Atlantic Oscillation (NAO) was responsible for this unexpected extreme Meiyu event. From 11 to 25 June with the positive NAO, the interaction between the South Asian High (SAH) and the western Pacific subtropical high maintained a warm front to strengthen the rainband north of the YR. Afterward, the coupling between SAH and midlatitude Mongolian Cyclone induced a cold front, which retreated the rainband to the south of YR from 30 June to 13 July with the negative NAO. Although the ECMWF S2S model successfully predicted the warm‐front‐related Meiyu rainband, it failed to forecast the Meiyu rainband in the cold‐front period, suggesting a great challenge of S2S forecasting on Meiyu rainfall. Key Points: Sequential warm Meiyu fronts in middle to late June and cold fronts in early to middle July directly cause record‐breaking Meiyu rainfall in 2020The NAO phase change leads to the alternation of the circulation regime of the East Asian summer monsoon from a warm‐ to cold‐front periodThe prediction skill of the ECMWF S2S model on the 2020 Meiyu rainband is higher in the warm front period but lower in the cold front period [ABSTRACT FROM AUTHOR]

Sequential heavy rainfall clusters and resultant severe winter flooding was observed over South China during the 2015/2016 super El Niño event. In the present, the intra‐seasonal oscillations (ISOs) related with heavy rainfall over East Asia from late autumn to early winter in 2015/2016 were investigated using the daily in situ rainfall records and the NCEP‐DOE Reanalysis data set. Results suggested that the successive heavy winter rainfall events in 2015/2016 were contributed by the ISOs with significant periods of 10–25 and 30–45 days. The wet phase of 10–25‐day ISO was jointly induced by the anomalous convergence of the low‐level water vapour associated with the tropical–subtropical interaction and the upper‐level divergence attributed to the eastwards propagating wavetrain. However in the wet phase of the 30–45‐day ISO, the anomalous upper‐level divergence was possibly caused by the weaker East Asian trough and the stronger barotropic westerly in subtropics. The 30–45‐day ISO can facilitate the eastwards propagation of the 10–25‐day ISO by providing a benefit upper‐level waveguide. Afterwards, the low‐level southwesterly surrounding the Tibetan Plateau gets enhanced to bring more moisture into South China where the winter flooding was serious in 2015/2016. In contrast, the more‐than‐normal winter rainfall was weaker in the super El Niño of 1997/1998 due to the lack of the 30–45‐day ISO. Therefore, the strongest winter rainfall anomaly over SC was ascribed to the superposition between the wet phases of 10–25 and 30–45‐day ISOs in 2015/2016. [ABSTRACT FROM AUTHOR]

Background: Extrahepatic cholangiocarcinoma (ECC) has become one of the most rapidly increasing malignancies in China during recent decades. The relationship between tobacco exposure and ECC epidemics is unclear; this study aimed to explore this relationship.Methods: We included 55,806 participants aged 30 years or older from the National Mortality and Smoking Survey of China. Smoking in participants and spouses was defined as 1 cigarette or more per day for up to 1 year. Spouses' smoking was taken as a measure of exposure to passive smoking. Smoking information in 1980 was ascertained and outcomes were defined as ECC mortality during 1986-1988.Results: We found that either passive or active smoking increased the risk of death from ECC by 20% (risk ratio [RR], 1.20; 95% confidence interval [CI], 0.99-1.47), compared with no exposure to any tobacco. This risk was a notable 98% (RR, 1.98; 95% CI, 1.49-2.64) for individuals exposed to passive plus active smoking. These findings were highly consistent among men and women. Pathology-based analyses showed dose-response relationships of ECC with pack-years for all types of smoking exposure (Ps for trend < 0.05); the RR reached 2.75 (95% CI, 1.20-6.30) in individuals exposed to combined smoking with the highest exposure dose. The findings were similar for non-pathology-based analysis.Conclusions: This study indicates that tobacco exposure increases ECC risk. Given the dramatic increase of exposure to secondhand smoke and patients with ECC, an inadequate provision of smoke-free environments could be contributing to ECC epidemics and could further challenge public health and medical services, based on the current disease spectrum. [ABSTRACT FROM AUTHOR]

The onset of South China Sea (SCS) summer monsoon (SCSSM) in June 2018 was extremely late following a La Niña event, indicating a breakdown in the traditional positive relationship between ENSO and SCSSM onset. Although the weaker western Pacific subtropical high in early May facilitated the SCSSM establishment, the persistent weaker Mongolian cyclone featured by an anomalous barotropic anticyclone over Northeast Asia during mid–late May dramatically postponed the SCSSM onset in 2018. This not only reduced upper‐tropospheric divergence over the SCS, which suppressed monsoon convection by attenuating the South Asian High, but cooled the mid–upper troposphere to decrease the in‐situ vertical easterly shear. The convection over the Maritime Continent was therefore trapped in the tropics, which further delayed the SCSSM onset via an enhanced local Hadley cell. It suggests a potential effect of triple SSTA mode in North Atlantic on the SCSSM onset by changing the mid‐latitudinal circulation. Plain Language Summary: The onset of South China Sea (SCS) summer monsoon (SCSSM) with large interannual variation, as the indicator of the beginning of the East Asian summer rainy season, has been widely concerned in the seasonal forecast. The ENSO events have been treated as the most important precursor of the SCSSM onset. An El Nino (La Nina) event was usually followed by the late (early) onset of SCSSM. However, this relationship was failed in 2018, when the SCSSM built up extremely late in June after a previous La Nina in the winter of 2017/18. The present work shows an additional potential precursor, the strong positive triple SSTA mode in North Atlantic, is able to delay the onset of SCSSM in 2018 by weakening the Mongolian cyclone in the mid‐high latitude. On the one hand, the weaker Mongolian cyclone could decrease the upper‐level divergence to suppress the convection over the SCS by attenuating the South Asian High. On the other hand, the colder troposphere comes up over the northern SCS to inhibit the in‐situ vertical easterly shear. Thus, the convection over the Maritime Continent is trapped in the tropics to further postpone the SCSSM onset by enhancing a local Hadley cell. Key Points: The La Niña event in the previous winter cannot explain the extremely late onset of the South China Sea summer monsoon (SCSSM) in 2018A persistent weaker Mongolian cyclone and its resultant attenuated South Asian High postponed the SCSSM onset in 2018The triple mode of spring SST anomalies in the North Atlantic may modulate the onset time of the SCSSM [ABSTRACT FROM AUTHOR]

Background/purpose: We assessed the effect of smoking on death from chronic obstructive pulmonary disease (COPD) in China by employing a large population-based, case-spouse control study design using data from a nationwide survey of mortality.Methods: During 1989-1991, a nationwide retrospective survey of mortality was conducted in China. For approximately 1,000,000 adults dying from all causes during 1986-1988, their surviving spouses or other informants provided detailed information about their own as well as the deceased person's smoking history. For this study, 183,393 individuals who died of COPD at age > or = 40 years were taken as cases, while 272,984 sex-matched surviving spouses of subjects who died from any cause were taken as controls.Results: COPD death rates for smokers were more than twice as high as those of non-smokers, with a dose-response risk pattern, despite the fact that COPD death rates varied widely by region and age. Tobacco accounted for 41.4% of COPD deaths in men, but only 13.5% of those in women, who had a lower rate of smoking.Conclusion: A case-spouse control study, as an alternative design, is valid and feasible in utilizing information from population-based, retrospective mortality survey data for an analytical epidemiological study of disease etiology. [ABSTRACT FROM AUTHOR]

Purpose: To examine age-related effects of smoking on lung cancer mortality in a large population-based case-control study that was incorporated into a nationwide retrospective survey of mortality in China. Methods: Two data sets were pooled for this analysis: national mortality survey data and data from a nationwide case-control comparison. These pooled data were used to calculate age-specific lung cancer death rates by smoking status and expected years of lost life expectancy for each smoking-associated death. Results: There was a significant excess of deaths (54% of urban deaths, 51% of rural deaths) at 35 to 69 years of age among male smokers and the average loss of life expectancy per smoking-associated death at these ages was 18.3 years. For women ages 35 to 69 years of age, 29% and 11% excess lung cancer mortality was observed in urban and rural smokers, respectively, with an average loss of life expectancy per smoking-associated death of 21.3 years. Conclusions: Tobacco smoking was associated with a large number of deaths from lung cancer. Utilizing information from a population-based retrospective mortality survey for conducting an analytic epidemiological study of main determinants of disease is feasible and can generate important results. [Copyright &y& Elsevier]

Annual cycle is fundamental in the East Asian monsoon (EAM) systems, profoundly governing the spatiotemporal distribution of the East Asian rainfall. The present study identified the dominant modes of the annual cycle in the East Asian rainfall based on the Fourier harmonic analysis and the Empirical Orthogonal Function (EOF) decomposition. We evaluated the performance of the first two leading modes (i.e., EOF-1 and EOF-2) in historical experiments (1979–2014) of the 21 released climate models of phase six of the Coupled Model Intercomparison Project (CMIP6). Comparing with the observation, although the CMIP6 models yield the essential fidelity, they still show considerable systematic biases in the amplitude and phase of the annual cycle, especially in east and south China. Most models exhibit substantial phase delays in the EOF-2 mode of the annual cycle. Some specific models (BCC-ESM1, CanESM5, and GFDL-CM4) exhibiting better performance could capture the observed annual cycle and the underlying physics in climatology and interannual variability. The limited fidelity of the EOF-2 mode of the EAM annual cycle primarily hinders the monsoon variability simulation and thus the reliable future projection. Therefore, the dominant modes of the EAM annual cycle act as the evaluate benchmark in the EAM modelling framework. Their improvement could be one possible bias correction strategy for decreasing the uncertainty in the CMIP6 simulation of the EAM. [ABSTRACT FROM AUTHOR]

Background: China is experiencing a postpeak smoking epidemic with accelerating population ageing. Understanding the impacts of these factors on the future cancer burden has widespread implications., Methods: We developed predictive models to estimate smoking-related cancer deaths among men and women aged ≥35 years in China during 2020-2040. Data sources for model parameters included the United Nations World Population Prospects, China Death Surveillance Database, national adult tobacco surveys and the largest national survey of smoking and all causes of death to date. The main assumptions included stable sex-specific and age-specific cancer mortality rates and carcinogenic risks of smoking over time., Results: In a base-case scenario of continuing trends in current smoking prevalence (men: 57.4%-50.5%; women: 2.6%-2.1% during 2002-2018), the smoking-related cancer mortality rate with population ageing during 2020-2040 would rise by 44.0% (from 337.2/100 000 to 485.6/100 000) among men and 52.8% (from 157.3/100 000 to 240.4/100 000) among women; over 20 years, there would be 8.6 million excess deaths (0.5 million more considering former smoking), and a total of 117.3 million smoking-attributable years of life lost (110.3 million (94.0%) in men; 54.1 million (46.1%) in working-age (35-64 years) adults). An inflection point may occur in 2030 if smoking prevalence were reduced to 20% (Healthy China 2030 goal), and 1.4 million deaths would be averted relative to the base-case scenario if the trend were maintained through 2040., Conclusions: Coordinated efforts are urgently needed to curtail a rising tide of cancer deaths in China, with intensified tobacco control being key., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Cigarette smoking is a prominent risk factor for a wide range of diseases. The current study aimed to evaluate the impact of smoking on deaths from major smoking-related diseases (neoplasms, vascular diseases and respiratory diseases) in Chinese adults by estimating the potential gains in life expectancy (LE) that would accrue from eliminating deaths from these diseases, and to determine the contribution of each disease to the reduction in LE associated with smoking., Methods: Two cohorts of Chinese smokers and non-smokers were constructed from a retrospective national mortality survey that had been conducted in 1989-1991 and included one million all-cause deaths among adults during 1986-1988 in 103 geographical regions. For each cohort, potential gains in LE by eliminating deaths from each major smoking-related disease were estimated. The contributions of each disease to smoking-associated reduction in LE were assessed using the LE decomposition approach., Results: Among the major smoking-related diseases, it was estimated that elimination of vascular diseases would provide the greatest potential gain in LE (years), regardless of smoking status. The gains for smokers versus non-smokers in populations of urban men, urban women, rural men and rural women aged 35 years were 3.5 vs. 4.3, 3.8 vs. 4.1, 2.4 vs. 3.0, and 2.6 vs. 2.9 years, respectively. Respiratory diseases contributed most to smoking-associated LE reductions in urban women, rural men and rural women of 43.6%, 46.4%, and 62.9%, respectively. In urban men, neoplasms contributed most to smoking-associated LE reduction, their contribution being estimated as 45.8%., Conclusions: Respiratory disease has the greatest influence on the LE reduction associated with smoking. Thus, smoking prevention could significantly reduce deaths from respiratory disease and improve LE.

Objectives: To provide a more accurate estimate of early smoking-attributable mortality and potential years of life lost using data from a representative study of 103 study areas in China., Methods: Two datasets were employed as follows. Firstly, retrospective national mortality survey data, which included a population of 67 million in 103 study areas, and about 1 million adults who died in 1986-1988; secondly, nationally representative case-control comparative data was extracted from the survey data to measure the effect of smoking on age trends in smoking-attributable mortality. Potential years of life lost, and sex differences in life expectancy in smokers and non-smokers in the total population aged 35 and over were also estimated., Results: Tobacco caused 11.2% (16.0% of men and 3.7% of women) of total deaths in 1987, and more than two-thirds of these excess deaths occurred between the ages of 50 and 74 years, but only less than 5% excess deaths occurred at ages under 50. Although life expectancies varied with region or sex differences, the years of life lost attributable to smoking was almost the same. Smokers at age 35 lost about 3 years of life expectancy in comparison with never smokers. The study also confirmed that more than 50% of the sex difference in life expectancy was accounted for by smoking., Conclusion: Fully understanding the consequences of smoking in relation to mortality can clarify its effects on the health and longevity of the entire population.

Purpose: To assess the validation of a novel control selection design by comparing the consistency between the new design and a routine design in a large case-control study that was incorporated into a nationwide mortality survey in China., Methods: A nationwide mortality study was conducted during 1989-1991. Surviving spouses or other relatives of all adults who died during 1986-1988 provided detailed information about their own as well as the deceased person's smoking history. In this study, 130,079 males who died of various smoking-related cancers at age 35 or over were taken as cases, while 103,248 male surviving spouses (same age range with cases) of women who died during the same period and 49,331 males who died from causes other than those related to smoking were used as control group 1 and control group 2, respectively. Consistency in the results when comparing cases with each of the control groups was assessed., Results: Consistency in the results was observed in the analyses using different control groups although cancer deaths varied with region and age. Equivalence could be ascertained using a 15% criterion in most cancer deaths which had high death rates in urban areas, but they were uncertain for most cancers in rural areas irrespective of whether the hypothesis testing showed significant differences or not., Conclusions: Sex-matched living spouse control design as an alternative control selection for a case-control study is valid and feasible, and the basic principles of the equivalence study are also supported by epidemiological survey data.