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Abstract 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 In 2023, the development of El Niño is poised to drive a global upsurge in surface air temperatures (SAT), potentially resulting in unprecedented warming worldwide. Nevertheless, the regional patterns of SAT anomalies remain diverse, obscuring where historical warming records may be surpassed in the forthcoming year. Our study underscores the significant influence of El Niño and the persistence of climate signals on the inter-annual variability of regional SAT, both in amplitude and spatial distribution. The likelihood of global mean SAT exceeding historical records, calculated from July 2023 to June 2024, is estimated at 90%, contingent upon annual-mean sea surface temperature anomalies in the eastern equatorial Pacific exceeding 0.6 °C. Regions particularly susceptible to recording record-high SAT include coastal and adjacent areas in Asia such as the Bay of Bengal and the South China Sea, as well as Alaska, the Caribbean Sea, and the Amazon. This impending warmth heightens the risk of year-round marine heatwaves and escalates the threat of wildfires and other negative consequences in Alaska and the Amazon basin, necessitating strategic mitigation measures to minimize potential worst-case impacts.

Migrasomes are newly identified vesicular structures that mainly come from the ends and crosspoints of retracting fibers in moving cells. Their creation is closely linked with cell movement and goes through three key steps: Nucleation, Maturation, and Expansion. They eventually get released in an event called migracytosis. Migrasomes have become an interesting focus in cell communication, especially during processes like development. They transport a mix of chemokines, growth factors, and morphogens. Their study can offer fresh perspectives on developmental gradients and improve our understanding of how development works. In the mini-review, we summarize our recent progress on the role of migrasomes in development, with a special focus on how migrasomes contribute to the spatial distribution of signalling molecules.

Recent years have witnessed contrasting trends in summer total rainfall (STR) over the Tibetan Plateau (TP), with an increase in the northern and a decrease in the southern TP. This study identifies four significant centers of rainfall trends: eastern TP (“region A”), Qiangtang Plateau (“B”), Qaidam Basin (“C”), and the northern foothills of the Himalayas (“D”). Heavy rainfall dominates STR trends in regions A and D, accounting for 55.6% and 52.0%, respectively. In region B, moderate and light rainfall contribute almost equally, accounting for 37.3% and 44.8% of the STR trend, respectively. Region C is primarily influenced by light rainfall, explaining 71.2% of the STR trend. Notably, the contributions of different rainfall intensities to STR in each region vary annually, with region A experiencing more heavy rainfall, region B having moderate dominance but less light rainfall, and region C and D showing reduced and increased light rainfall contributions, respectively. Mechanistically, the strengthening of the upper-level westerly jet and the South Asian High, coupled with changes in moisture transport and convective available potential energy, collectively cause variations in rainfall intensity, characterizing the spatial heterogeneity in STR in the TP.

Historical extreme heatwaves struck the Yangtze River Valley (YRV) in the boreal summer of 2022, severely impacting agricultural production, electricity supply, and resident health in China. This study shows that extreme heatwaves recurred over the YRV with distinct subseasonal processes. In early summer, from 14 June to 18 July, two extreme heatwaves were embedded in a mid-latitude 10–25-day intraseasonal oscillation (ISO), and hot-and-wet anomalies persisted over the YRV. A self-sustaining mechanism between the “cold vortex” over Northeast China and the “heat dome” around the YRV maintained this bi-weekly ISO. It fueled the heatwaves by modulating the meridional advection of upper-tropospheric potential vorticity, which firstly warmed the air via adiabatic processes and then later by diabatic heating. In late summer, from 30 July to 29 August, a 30–50-day ISO impacted the heatwave and drought over the YRV. This ISO originated from monsoon convection in the tropics, which regulated the meridional monsoonal circulation and enhanced the heatwave by intensifying the descending air motion and adiabatic heating over the YRV. The alternation of the two ISOs accompanied the northward migration of the subtropical westerly jet over East Asia. The combination of the above-normal 10–25-day ISO and the moderate 30–50-day ISO led to the three consecutive extreme YRV heatwaves in 2022.

Regional persistent extreme cold events are meteorological disasters that cause serious harm to people’s lives and production; however, they are very difficult to predict. Low-temperature weather systems and their effects have a significant low-frequency oscillation period (10–20 d and 30–60 d). This paper uses deep learning to analyze the extended-range time scale and predict regional persistent extreme cold events. The dominant low-frequency oscillation components of cold events are obtained via wavelet transform and Butterworth filtering. The low-frequency oscillation component is decomposed via empirical orthogonal function decomposition to extract the main spatial mode and time coefficient. A convolutional neural network is used to establish the correlation between large-scale circulations and the time coefficient of the low-frequency oscillation component of the lowest temperature. The proposed deep learning model exhibits good prediction accuracy for regional persistent extreme cold events with low-frequency oscillations.

Abstract 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 ( 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 The onset of the Asian summer monsoon (ASM) starts the rainy season in one of the most world populous regions. The present study found that the stepwise ASM onset process (ASMOP) in the Bay of Bengal, South China Sea (SCS), and India exhibits three distinct interannual modes induced by different sea surface temperature anomalies (SSTAs). The first mode features are in‐phase variation of ASMOP in southern Asia, which originates from the ENSO‐related SSTAs and anomalous circulations in the tropical Indo‐Pacific Ocean. The second mode indicates the anomalous ASMOP in India and depends on the southwestern Indian SSTAs that alter the low‐level cross‐equatorial flow over the Arabian Sea. In the third mode, the western North Pacific SSTAs and their resultant circulation anomalies regulate ASMOP in the northern SCS. These extra‐equatorial SSTAs and their associated air‐sea interaction serve as an additional source of seasonal predictability for ASMOP besides El Niño–Southern Oscillation events.

Yunnan Province in Southwest China is vulnerable to droughts due to its distinctive topography and local climate. Spring drought in Yunnan (SDY), which accounts for 70% of all drought events, causes the most severe devastation. By examining the variation characteristics of droughts in Yunnan from 1961 to 2020 in terms of the standardized precipitation evapotranspiration index (SPEI), this present study shows that droughts in Yunnan have worsened in the past 60 years on different timescales. Especially, the SDY exhibits notable interannual and interdecadal variations, with no significant long-term trend, although the spring average regional temperatures have risen at a rate of 0.33 °C/10a since 1961. Here, in order to quantify the contribution of the precipitation and temperature, the two main meteorological impact factors, to the SDY under the exacerbation of climate warming, the statistical analyses reveal that precipitation plays a more crucial role than temperature in interannual and interdecadal SDY variations. Further, a diagnostic analysis of the moisture budget equation indicates that suppressed vertical moisture advection is the most important physical process affecting the reduced rainfall amount in spring, followed by the restricted horizontal water vapor transport. Meanwhile, the weak Bay of Bengal (BOB) summer monsoon, which is likely regulated by El Niño-like sea surface temperature anomalies (SSTAs) in spring, is closely linked with the SDY. This mechanism provides the possibility of SDY predictability on a seasonal scale.

The frequency of tornadoes usually peaks during spring to summer rather than winter in climatology. However, the United States (U.S.) experienced more than 200 tornadoes in December 2021, which broke the historical record and caused 87 fatalities. Historically, the frequency of tornadoes in December tends to increase under El Niño conditions. Our results show that the monthly large-scale weather regime conducive to these record-breaking tornado outbreaks under a La Niña condition is closely associated with Typhoon Nyatoh in the western North Pacific. As the tropical cyclone (TC) recurved into the mid-latitudes, its interaction with the extratropical flows has caused distortions in the Asian jet stream and the dramatic development of anomalous anticyclone west of the dateline, which in turn strongly regulated the response of the monthly atmospheric teleconnection to La Niña forcing. Accurate forecasts of the monthly mean circulation for December 2021 first appeared in the European Center for Medium-Range Weather Forecasts sub-seasonal to seasonal forecasts from 29 November, with a forecast skill closely related to that of Typhoon Nyatoh. Given most studies on the warm seasons with frequent tornadoes, the present results advance our understanding of the TC effect on the monthly atmospheric response to El Niño-Southern Oscillation forcing and its linkage to the tornado occurrence during boreal winter.

Vertebrate telencephalon formation requires Foxg-Fgf8 cross-regulation, but while ascidians express Foxg in the neural plate, they lack a telencephalon. Here the authors show that Foxg loss does not affect ascidian brain formation, indicating that telencephalon evolution required recruitment of Fgf downstream of Foxg.

The interannual variation of snowfall over the Tibetan Plateau (TP) in early winter (November–December) and its related atmospheric attribution are clarified. Meanwhile, the influence of tropical sea surface temperatures (SSTs) on TP snowfall is investigated by diagnostic analyses and Community Atmosphere Model (CAM5) simulations. The leading mode of TP snowfall in early winter features a spatially uniform pattern with remarkable interannual variability. It is found that the Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO) are main external forcing factors for TP snowfall. Positive IOD with positive ENSO and positive IOD with neutral ENSO cases both have remote impact on motivating Southern Eurasia (SEA) pattern, which can induce an anomalous cyclone around the TP. The corresponding anomalous ascending motion and cold air in the mid-upper troposphere provide the dynamical and thermal conditions for heavy snowfall. The low-level southwesterly winds are enhanced over the Arabian Sea and Bay of Bengal, bringing abundant water vapor into the TP for excessive snowfall. Furthermore, CAM5 simulation experiments forced by IOD- and ENSO-related SST anomalies are performed to verify their combined and independent effects on TP snowfall in early winter. It is confirmed that either positive IOD or El Niño has certain impacts on motivating circulation anomalies favorable for snowfall over the TP. However, IOD plays a leading role in producing the excessive snowfall-related atmospheric conditions, and there is an asymmetric influence of ENSO and IOD on the TP snowfall.

Abstract 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 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

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.

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 ≥ 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.

There exists a pronounced asymmetry between the amplitudes of central Pacific (CP) and eastern Pacific (EP) El Niño sea surface temperature anomalies (SSTA). The present study examines such an asymmetry and its relationship with the North Pacific SSTA. Results indicate that the weaker CP El Niño amplitude can be attributed to the weaker anomalous zonal wind response to the east–west equatorial SSTA gradient during its growing phase compared with EP El Niño. Furthermore, the occurrence of CP El Niño is closely associated with southwesterly surface wind anomalies in the subtropical North Pacific, as well as ocean warming reminiscent of the North Pacific Gyre Oscillation (NPGO) pattern in its vicinity. Both the observations as well as the pacemaker experiments with a coupled global climate model suggest that the anomalous low-level southwesterlies, induced by the North Pacific Oscillation (NPO)-like atmospheric variability, can enhance anomalously positive SST signals and extend them southwestward to the central equatorial Pacific via the wind–evaporation–SST feedback. This will further attenuate the atmospheric response to zonal SSTA gradient, and hence weaken the amplitude of CP El Niño. Therefore, anomalous low-level southwesterlies over the subtropical North Pacific can effectively act as a conduit for tropical–subtropical air–sea interaction in that region, and can play an important role in limiting the intensity of CP El Niño. [ABSTRACT FROM AUTHOR]

The northward shift of the Western North Pacific Subtropical High (WNPSH) in July 2018 broke the historical record since 1958 and resulted in extreme heat waves and casualties across Northeast Asia (NEA). In the present work, we associated this extreme WNPSH anomaly with the anomalies of barotropic anticyclone above NEA originating from the strongest positive tripole pattern of sea surface temperature anomaly (SSTA) in the North Atlantic in July. Both data analysis and numerical experiments indicated that the positive tripole SSTA pattern could produce an upper-tropospheric wave source over Europe, which stimulated an eastward propagating wave train along the subpolar westerly jet over the Eurasian Continent. When its anticyclonic node reached NEA, the WNPSH started to shift northward. After the cyclonic node in the circulation anomaly encountered the Tibetan Plateau (TP), atmospheric diabatic heating was enhanced over the eastern TP, initiating another subtropical wave train, which furthered the northward shift of the WNPSH. Therefore, the wave source over Europe was critical for the northward shift of the WNPSH in July, connecting the tripole SSTA pattern in the North Atlantic with the WNPSH anomaly and maintaining the downstream effects of thermal forcing over the eastern TP on the East Asian summer monsoon. [ABSTRACT FROM AUTHOR]

This paper reviews progress in the study of Tibetan Plateau (TP) climate dynamics over the past decade. Several theoretical frameworks, including thermal adaptation and the TP sensible heat (SH) driving air-pump, have been developed to identify the mechanisms responsible for the circulation anomaly produced by thermal forcing of the TP. Numerical simulations demonstrate that the thermal effects of large-scale orography, including the Tibetan and Iranian Plateaus (TIP), are crucial for the formation of the East Asian and South Asian summer monsoons (SASM) because the surface SH of the TIP is the major driver of the water vapor transport required for the genesis of the north branch of the SASM.The large-scale orography of the TP affects the Asian climate through thermal forcing in spring and summer, and mechanical forcing in winter. The TP forcing can also influence the Asian summer monsoon (ASM) onset over the Bay of Bengal (BOB) by enhancing the BOB warm pool at the surface and by modulating the South Asian High (SAH) in the upper troposphere. On intra-seasonal timescales, the TP thermal forcing significantly modulates spring rainfall in southern China and generates the biweekly oscillation of the SAH in summer. Despite climate warming, the atmospheric heat source over the TP, particularly the spring SH, exhibits a clear weakening trend from the 1980s to 2000s. This weakening of the spring SH contributed to the anomalous 'dry in the north' and 'wet in the south' rainfall pattern observed over East China. Also discussed are challenges to further understanding the mechanism of TP forcing on the multi-scale variability of the ASM. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]